The most comprehensive vitamin B12-deficiency symptom list on the internet!

If you recognise any symptoms, make sure it's not a vitamin B12 deficiency. This is important because not only will symptoms caused by a vitamin B12 deficiency get worse over time, more complaints may develop as well.

• Neurological signs and symptoms
• Cardiovascular problems
• Psychological and/or psychiatric problems
• Other signs and symptoms
• Babies and children

Do you recognise 7 symptoms or more, than there's a good chance you suffer from a vitamin B12 deficiency.
A test treatment is advised.

Neurological signs and symptoms

• Cramps, tingling in feet and hands and later in legs, arms and face as well. "Feeling like there's electricity running through you", "there are ants crawling up my legs - it's driving me crazy". Also: a strange numb sensation in the hands and feet. Loss of function. Tremor of the hands. ^{20 21 22 23 24 25}
• Hyperesthesia, nerve pain(neuropathic pain). Caused by damaged nerve endings. “Oversensitivity or overstimulation of the tactile nerve endings in (parts of) the skin, that can be tingling, irritating or painful. The cause can be located either in the skin (inflammation of the nerve ending for instance) or located more centrally”. ^{26 27}
• Having to pee a lot, hypertonic bladder, bladder incontinence (not being able to hold your pee). ^{28 29 30 31 32}
• Headaches ^{33 34 35 36}
• Migraines ^{37 38 448 449}
• Restless leg syndrome ^{39 40 41 42}
• Ataxia, coordination problems, lowered sense of position. Instable, clumsy gait, drunken gait, or even not being able to walk at all. The mobility scooter/wheelchair phase has then arrived. And with it, all kinds of adjustments (such as a stair elevator) are required in your home. ^{43 44 45}
• Dizziness ^{46 47 48}
• Unexplained falling, fractures, also: dropping objects for no reason. Or: not having the strength to get open jars. ^{49 50 51 52 53 54}
• Osteoporosis (decrease in bone mass, increasing the chance of fractures and degenerative arthritis). Decreased activity of osteoblasts (cells that generate new bone). ^{55 56 57}
• Eye problems, macular degeneration ^{58 59 60 61 62 63}
• Decreased or loss of sight ^{64 65 66 67}
• Damage to optic nerves ^{68 69 70}
  Causing:
• Strange vibrations in the eye, flashes of light contracting vibrations of the eyelids (strange tics). ^{71 72}
• Optical neuropathy (lessened perception of colour, blurred vision, trouble seeing in the dark, field of vision failure). ^{73 74}
• Damage to optic nerve, inflammation, paralysis, infection or atrophy. ⁷⁵
• Hearing disorders, decreased hearing, distorted hearing. ^{76 77 326}
• Tinnitus ^{78 79 80 81}
• Joint pain, muscle soreness, especially in the hips, but also in the wrists and other joints. Symptoms partly resemble fibromyalgia. The patient complains about a stiff and heavy feeling in the legs. There is an unstable gait and muscle soreness is a lot worse than before. Leg pain while walking. There are often problems with fine motor skills as well (fastening small buttons or getting small coins from a wallet are difficult) ^{82 83}
• Lower back pain ^{84 85 86}
• Strange feeling in the feet feeling like you're walking on felt, cotton balls or cushions; distorted surface sensation. Hanging foot. ^{87 88}
• Walking disorders ^{89 90 91}
• Numb feeling in limbs, Quote: “Sensation of the surface in the lower body and the legs is greatly decreased or almost disappeared.” ^{92 93}
• Weakening in the legs, trunk or other parts of the body (even the voice). ^{94 95 96 97}
• Paralysis ^{98 99 100 101 102 103 104 105}
• Complaints of ageing, such as forgetfulness, tiredness, depression, shaking limbs, cardiac arrhythmia, balancing problems, falling (and fractures), osteoporosis, disabled sight and hearing, may often be connected to a chronic vitamin B12 deficiency. ^{106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129}
• Heartburn and other stomach complaints ^{130 131 132}
• Early aging ^{133 134 135 136 137 138 139 140 141 142 143 144 333}
• Subacute combined degeneration of the spinal cord, which is a damaging of the dorsal cords in the bone marrow and the pyramidal lateral cords. Sometimes the disease is paired with affected peripheral nerves. (Polyneuropathy) The disease is caused by a vitamin B12 deficiency. B12 is necessary for maintaining the myelin sheaths, the insulating layers around the nerve bundles. Damaged myelin sheaths (sometimes permanently) cause paresthesia symptoms. These are tingling sensations, "pins and needles" in the toes and the feet, and later in the fingers. Sometimes the tingling lessens during sleep, but after awakening it starts again. ^{1 2 3 4 5 6 7 8 9 10 11 12 13}
• High sensitivity, because the entire nervous system is affected by a vitamin B12 deficiency: the soft fatty material (myelin) that envelops and protects our nerves is damaged (demyelination).
  This is comparable to stripping an electric wire. It leads to all sorts of strange symptoms; tingling, pain in the arms and legs, etc., and also leads to extreme sensitivity to stimuli, sounds, light, moods and ‘energies’ of other people. Patients are very touchy, vulnerable, easily frightened. Also leads to greater exhaustion and irritability. ^{14 15 16 17 18 19}
• Alzheimer's (including early-onset); a daily dose of vitamin B12 lowers the risk of early dementia and Alzheimer's by 30 percent, according to research published in the American Journal of Clinical Nutrition. Researchers followed 1648 seniors between the ages of 65 and 90 over a period of 10 years. Vitamin B12 has the property to drastically lower a high and harmful homocysteine level. This decreases the amount of cardiovascular damage and brain damage with increasing age. ^{145 146 147 148 149 150 151 152 153 154 155 327}
• Parkinson's (including early-onset). Note: The use of the drug Levodopa, often prescribed to Parkinson's patients, may lead to a vitamin B12 deficiency. ^{156 157 158 159 160 161 162 163 164 165}

Cardiovascular problems

A vitamin B12 deficiency leads to elevated homocysteine values. Elevated homocysteine values are a significant risk factor for cardiovascular disease (comparable to high cholesterol).

• Pernicious anaemia ^{166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 328}
• Enlarged spleen or liver ^{182 183 334}
• Thyroid disorders ^{184 185 186 187 188 329 542 543}
• Haematological disorders: enlarged red blood cells (macrocytes); hypersegmented neutrophil granulocytes; oval cytosis. ^{189 190 191 192 193}
• Macrocytosis (enlarged red blood cells). ^{194 195}
• Blood clots ^{196 197 198}
• Cardiovascular problems ^{199 200 201 202 203 204}
• Deep-vein thrombosis (blood clot in arm or leg). ^{205 206 207 208 209}
• Elevated homocysteine levels, as a result of a vitamin B12 deficiency. Homocysteine is a potentially dangerous amino acid. When homocysteine accumulates in the bloodstream, the risk of coronary heart disease, stroke and blood clots increases significantly. A high homocysteine level can damage blood vessels and help cause atherosclerosis with an increased risk of heart attacks and strokes (developed in a relatively short time). Homocysteine can also transform cholesterol into its harmful form, increasing the chance of blood vessels being damaged. It can also contribute to the disruption of the functioning of the endothelial cells (inside of the blood vessels). When pregnant, an elevated homocysteine level in the blood can also increase susceptibility to preeclampsia, a potentially dangerous complication of the pregnancy characterised by high blood pressure. ^{210 211 212 213 214 215 216 217 218 219}
• Dizziness, vertigo, balance problems (combined with cardiovascular disease). ^{220 221 222}
• Orthostatic hypotension (blood pressure is too low while standing, causing fainting). ^{223 330}
• Shortness of breath and chest pain; angina. ^{224 225 335}
• Coronary heart disease ^{226 227 228}
• Increased risk of cardiovascular disorders, arteriosclerosis and arterial and venous thromboembolism, cerebrovascular accidents. ^{229 230 231}
• (minor) TIA/CVA (stroke), "silent brain infarcts". ^{232 233 234 235 236 237 238}
• Heart attack ^{239 240 241 242 243}
• Heart palpitations ^{244 245}
• Cardiac arrhythmia, fast pulse or weak, low pulse. ^{246 247}
• Lung disease; lung embolism (blood clots in the lungs). ^{248 249 250 251}

Psychological and/or psychiatric problems

• Confusion ^{252 253 254 255}
• Anxiety ^{256 257 258 331}
• Psychiatric disorders: mood swings; depersonalisation; personality shifts (“you don't feel like yourself anymore”), suspicion, paranoia, behavioural shifts. ^{259 260 261 262 263 264 265 266 267}
• Compulsive behaviour, aggression, violent behaviour ^{268 269 270 271 272}
• Perception disorder, paranoid delusions (for instance completely miscomprehending what someone is trying to tell you). ^{273 274 275 276 277}
• Hallucinations ^{278 279 280 280}
• Bipolar disorder (manic depression). ^{282 283 284}
• Schizophrenia ^{285 286 287 288 336 758}
• Developmental disorders such as ADHD, PDD-NOS and autism ^{289 290 291}
• Autism problems in initiating and allowing contact; behavioural, cognitive, and motor skill problems; unexpected mood shifts. ^{292 293 294 295}
• Depression, feeling down; no will to live, no more passion for anything; giving up; indifference; apathy (lack of interest); being (“fed up'”); lack of empathy. Low B12 values are strongly associated with experiencing depression. ^{296 297 298 299 332}
• Lack of concentration, no longer being able to think clearly, “brain fog”, drowsiness, light-headedness. ^{300 301 302 303}
• Intelligence, unused IQ potential. ^{304 305 306 307 308 309 310 311}
• Forgetfulness, short-term memory problems. ^{312 313 325}
• Difficulty finding words when speaking ^{314 315}
• No sense of wellbeing, the joy of living, the -‘joie de vivre'’; the humour, putting things into perspective, the will, the flair: bit by bit, it feels as if it has all been squeezed out and is creeping away. There is an increasing feeling of crankiness, moodiness, irritability ("having a short fuse"), of possible sudden aggression and/or mood changes. There can be an increase in unreasonable behaviour, even up to severe psychological complaints, panic attacks and even suicidal behaviour. ^{316 317 318 319 320}
• Trouble sleeping ^{321 322 323 324}
• Psychosis ^{337 338 339 340 341 342 343 344 345}
• Postnatal depression or psychosis, partly due to the enormous force and energy a birth requires, the physical and mental balance of a woman, which was precarious to begin with due to vitamin B12 deficiency, can suddenly shift dramatically. ^{346 347 348}
• Neurological complaints and loss of function caused by nitrous oxide, using N₂O) acutely causes a dangerous vitamin B12 deficiency. ^{349 350 351 352 353 354 355}
• Dementia (including early-onset). ^{356 357 358 359 360 361 362 363 364 365 366 367}

Other signs and symptoms

• Tiredness (somnolence), sleepiness, overall weakness; simply no energy, being in bad shape, signs of exhaustion (“waking up tired”). Also related to this: easily brought to tears and getting emotional, no longer being resistant to stress, being stressed out, burned out, exhausted, literally floored. A typical quote from a ‘vitamin B12 patient’: “I really feel like a geriatric in a young body” (many health complaints that are linked to old age are actually typical vitamin B12 deficiency symptoms). ^{368 369}
• Chronic Fatigue Syndrome (CFS) ^{370 371 372 373 374 375}
• Fibromyalgia ^{376 377 378 379}
• Sleepiness (needing a lot of sleep, spontaneously falling asleep), quickly getting tired after (minimal) exertion, and recovering poorly from it. ^{380 381 382 383 384}
• Sleeping disorders ^{385 386 387 388 389}
• Low or lowered immune system (like with AIDS), which causes a lot of illness, many health complaints, ailments (such as flu-like symptoms). A vitamin B12 deficiency increases susceptibility to infectious diseases in all possible organs. ^{390 391 392 393}
• Fever (with no clear cause). ^{394 395 396}
• Increased risk of vaginal and urinary tract infections and other infections ^{397 398 399 400 401}
• Chronic coughing ^{402 403}
• Poor/slow healing of wounds ^{404 406}
• Asthma, shortness of breath ^{407 408 409 410}
• Often being cold ^{411 412 413}
• Burning sensation on the skin ^{414 415 416 417}
• Inflammation in the gastrointestinal tract (even including perforated intestines), burping often. ^{418 419}
• Nausea ^{420 421 422}
• Diminished metabolism ^{423 424}
• Poor digestion (pain in the upper abdomen), full or bloated feeling even after eating small or normal portions. ^{425 426 427}
• Less to no appetite ^{428 429 430 431}
• Gluten intolerance ^{432 433 434 435 436}
• Anorexia ^{437 438 439 440 441 442 443}
• Abdominal pain ^{444 445 446 447}
• Stomach ulcer ^{450 451 452}
• Intestinal complaints, inflammatory bowel disease (IBD) ^{453 454 455 456 457 458 459 460 461}
• Crohn's disease ^{462 463 464 465 466 467 468 469 470 471 472 473 474}
• Ulcerative colitis ^{475 476 477 478 479}
• Liver disorders ^{480 481}
• Diarrhoea (fairly regular) ^{482 483 484 485}
• Kidney failure, renal disorders ^{486 487 488 489 490 491}
• Severe constipation ^{492 493 494 495}
• Irregular bowel movements ⁴⁹⁶
• Gas ⁴⁹⁷
• Weight loss (partly due to diminished appetite). ^{498 499 500 501 502}
• Loss of taste and/or smell ^{503 504 505}
• Painful tongue (glossitis), so called ‘beefy-red tongue’, especially troublesome with spicy foods and acidic drinks and while brushing teeth, taste of iron and/or metal in the mouth. ^{506 507 508 509 510 511 512}
• Periodontitis, infected gums leading to other oral health problems. ^{513 514 515}
• Allergies for dust, mould, food, hay fever, certain metals. ⁵¹⁶
• Epilepsy (West syndrome), epileptic seizures ^{517 518 519}
• Diabetes Mellitus, Note: Using the drug Metformin, often prescribed to diabetes patients, may lead to a vitamin B12 deficiency ^{520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536}
• Exocrine Pancreatic Insufficiency (EPI), poorly functioning pancreas, often also caused by an auto-immunity problem ^{537 538 539 540}
• Oral aphthae, vitamin B12 also helps in combating aphthae ^{544 545 546}
• Acne ^{547 548 549 550}
• Rheumatoid arthritis ^{551 552 553}
• Skin diseases and complaints, eczema, red spots, psoriasis, shingles, extremely dry skin, extreme itch ^{554 555 556 557 558}
• Noticeable paleness of the face, or a noticeable pale yellow or grey complexion of the skin. ^{559 560 561}
• Vitiligo (disappearance of pigment in the skin). ^{562 563 564 565 566 567}
  Or:
• Hyperpigmentation, pigment spots, spontaneous bruising. ^{568 569 570 571}
• Dysphasia problems with speaking, using wrong words, trouble finding the right words, "slurred speech" keyboard aphasia. ^{572 573 574}
• Hair loss (Alopecia Areata), baldness, hair growing thinner or ‘rougher’ losing your eyebrows. ^{575 576}
• Premature greying of the hair ^{577 578 579}
• Unhealthy brittle nails, split and tear easily. ^{580 581 582}
• Neck and/or lower back pain ^{583 584 585 586}
• Incontinence ^{587 588 589 590 591}
• Menstruation problems (painful, irregular, sometimes too long, sometimes stays away). ^{592 593}
Remarkable: Vitamin B12 deficiency can also lead to:
• Abnormal PAP-smear results in women, a vitamin B12 deficiency can lead to blood anomalies. These blood anomalies can affect the uterine wall and the cervix. Which can lead to abnormal cell production in the cervix (dysplasia). These can incorrectly be diagnosed as early-stage cervical cancer. ^{595 596 598}
• Dysplasia (abnormal cell division in the cervix). ^{599 600 601}
• Severe menopausal complaints ^{602 603}
• Increased risk of cancer, a vitamin B12 deficiency can lead to an increasingly large amount of damage done to the DNA and alters methylation of the DNA, both factors are known as important factors in cancer risk. ^{604 605 606 607}
  Note: there is also evidence showing that extra vitamin B12 supplementation inhibits the proliferation of cancer cells. ^{608 609 610 611 612}
• Breast cancer Quote: there is mounting evidence linking deficient levels of B12 to breast cancer. Pp 22, 146“Could it be B12?” Sally M. Pacholok and Jeffrey M. Stuart ^{613 614}
• Stomach cancer, increased risk of ^{615 616 617 618 619 620}
• Liver cancer, increased risk of ^{621 622}
• Intestinal cancer, increased risk of ^{623 624 625 626}
• Cervical cancer, increased risk of ^{627 628 629 630 631 632 633}
• Lung cancer, increased risk of ^{634 635}
• Mouth cancer, increased risk of ^{636 637}
• Infertility among women, increased risk of ^{638 639 640 641 642 643}
• Lower quality sperm in men ^{644 645 646}
• (Repeated) miscarriages, increased risk of ^{647 648 649 650 651 652}
• Birth defects, increased risk of (for instance neural tube defects, brain injury, spina bifida, congenital heart defect, growth retardation in the uterus) ^{653 654 655}
• Premature birth, increased risk of ^{656 657 658}
• Loss of libido (m/f) ⁶⁵⁹
• Erectile dysfunction ⁶⁶⁰
• Bulimia (bulimia nervosa). ⁷⁵⁹
• All auto-immune diseases are suspect of being associated to a vitamin B12 deficiency ^{661 662 685}
  For example:
  Multiple Sclerosis (MS) ^{663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683}
  ALS (Amyotrophic Lateral Sclerosis) ⁶⁸⁴

In babies and children

Symptoms listed below are also part of the overall symptoms list, but here references to research that has been done with regards to children are listed.

If a woman has a vitamin B12 deficiency, it is very likely that her baby will also have a vitamin B12 deficiency. Vitamin B12 is passed on during foetal development and through the breast milk.

It is estimated that 2 to 5% of all children suffer from a vitamin B12 deficiency. In the Netherlands, that would mean tens of thousands of children. A vitamin B12 deficiency in children can lead to:

• Intrauterine growth restriction ^{686 687 688 689}
• Congenital conditions related to the neural tube defects (spina bifida). ^{690 691 692 693 694 695 696 697 698 699}
• Failure to thrive, neurological and motor disorders, dysfunction, paralysis ^{700 701 702 703 704 705 706 707 708 709 710 711 712 713}
• Mental retardation, delayed learning development ^{714 715 716 717 718 719 720}
• No appetite ^{721 722 723}
• Epilepsy, (West syndrome), epileptic seizures. ^{724 725 726}
• Hematologic disorders ^{727 728}
• Apathy ⁷²⁹
• Problems concentrating, difficulties finding words, memory problems ^{730 731 732}
• Lower mental achievement(s) ^{733 734 735 736}
• Irritability, behavioural issues, impatience, aggression. ^{737 738 739}
• Thyroid disorders ^{740 741}
• Speech problems (learning to talk occurs much later and not as well as it should), allergies (food, dust, metals, etc.) ⁷⁴²
• Noticeably pale face ⁷⁴³
• Eczema, skin problems ⁷⁴⁴
• Toilet-training problems, incontinence ⁷⁴⁵
• Cardiac arrhythmia ⁷⁴⁶
• Loss of strength in arms and legs (sometimes leading to wheelchair use). ⁷⁴⁷
• Severe reaction to vaccinations ⁷⁴⁸
• ADHD ⁷⁴⁹
• PDD-NOS ⁷⁵⁰
• Autism ^{751 752 753 754}
• Abnormal brain CT/MRI/EEG, brain atrophy ^{755 756}
• Infantile colic ^{757 758}

References

Neurological signs and symptoms

• Subacute combined degeneration of the spinal cord, which is a damaging of the dorsal cords in the bone marrow and the pyramidal lateral cords. Sometimes the disease is paired with affected peripheral nerves (Polyneuropathy). The disease is caused by a vitamin B12 deficiency. B12 is necessary for maintaining the myelin sheaths, the insulating layers around the nerve bundles. Damaged myelin sheaths (sometimes permanently) cause paresthesia symptoms. These are tingling sensations, “pins and needles ” in the toes and the feet, and later in the fingers. Sometimes the tingling lessens during sleep, but after awakening it starts again and the patient feels as if “the body coming back to life”.
  ¹ Gecombineerde strengziekte door vitamine-B12-deficiëntie: eenvoudige diagnose, effectieve therapie; J.C.F.Jongen, P.J.Koehler en C.L.Franke Ned Tijdschr Geneeskd 2001 30 june;145(26)
  ² Mazure, A.; Bieger, R.; Lambrecht, P.C.L.A.; Wiarda, K.S. ~ Macrocytose, polyneuropathie en achterstrengstoornis door malabsorptie van eiwitgebonden vitamine B12. Nederlands Tijdschrift voor de Geneeskunde. 1990; 134 (13): 660 - 662.
  ³ Cerebral Manifestations of vitamin B12 deficiency by J. MacDonald Holmes, M.D., F.R.C.P. Dec. 15, 1956 British Medical Journal.
  ⁴ Kunze, K.; Leitenmayer, K. ~ Vitamin B12 deficiency and subacute combined degeneration of the spinal cord.
  ⁵ Handbook of clinical neurology. Vinken, P.J.; Bruyn W.G. 1977: vol 28 no 6 1977. Elsevier, Amsterdam, pp 141 - 198.
  ⁶ Blz. 80, 90, 99, 101-103, 154, 192, 200, 204, 205, 222, 226 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷ Bij ziekenhuisopname op intensive care, is “Vitamine B12” vaak een gemiste invalshoek om de patient nog betere zorg te kunnen verlenen: “Vitamine B12, de vergeten ‘intensive care-vitamine” (bron: www.ortho.nl) 
  ⁸ Manzanares W, Hardy G. Vitamin B12: the forgotten micronutrient for critical care. Curr Opin Clin Nutr Metab Care 2010; 13(6):662-8. * Verjaal, A.; Timmermans-van den Bos, A.H.C.C.
  ⁹ Combined degeneration of the spinal cord due to deficiency of alimentary vitamin B12. Journal of Neurology, Neurosurgery and Psychiatry. 1967; 30: 464 - 467.
  ¹⁰ Subacute combined spinal cord degeneration and pancytopenia secondary to severe vitamin B12 deficiency. Cabrerizo-García JL, Sebastián-Royo M, Montes N, Zalba-Etayo B. Sao Paulo Med J. 2012;130(4):259-62. 
  ¹¹ Vitamin B12 deficiency in the brain leads to DNA hypomethylation in the TCblR/CD320 knockout mouse. Fernàndez-Roig S, Lai SC, Murphy MM, Fernandez-Ballart J, Quadros EV. Nutr Metab (Lond). 2012 May 18;9:41.
  ¹² Deficiency diseases of the nervous system. Bradley WG, Daroff RB, Fenichel GM, Jankovic J, eds. Bradley: Neurology in Clinical Practice. 5th ed. Philadelphia, Pa: Butterworth-Heinemann
  ¹³ Elsevier; 2008:chap 61. Gecombineerde strengziekte door vitamine-B12-deficiëntie: eenvoudige diagnose, effectieve therapie; J.C.F.Jongen, P.J.Koehler en C.L.Franke Ned Tijdschr Geneeskd 2001 30 juni;145(26)
• High sensitivity, because the entire nervous system is affected by a vitamin B12 deficiency: the soft fatty material (myelin) that envelops and protects our nerves is damaged (demyelination).
  This is comparable to stripping an electric wire. It leads to all sorts of “strange” symptoms and “tingling”, and pain in the arms and legs, etc., and also leads to extreme sensitivity to stimuli, sounds, light, moods and “energies” of other people. Patients are very touchy, vulnerable, easily frightened. Also leads to greater exhaustion and irritability.
  ¹⁴ Blz. 45, 65, 70, 86, 88, 100, 102, 105, 154, 191 “Is het Misschien B12-tekort?” - Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁵ Fine, Edward J. ~ The neurophysiological profile of vitamin B12 deficiency. Muscle and Nerve. 1990; 13: 158 - 164.
  ¹⁶ Mayer, R.F. ~ Peripheral nerve function in vitamin B12 deficiency. Archives of Neurology. 1965; 13: 355 - 362.
  ¹⁷ McCombe, P.A.; McLeod, J.G. ~ The peripheral neuropathy of vitamine B12 deficiency. Journal of Neurological Sciences. 1984; 106: 117 - 126.
  ¹⁸ Melson, H.; Kornrad, S. ~ Reversible neuropathy of vitamin B12 deficiency with normal hemoglobin serum vitamin B12. Lancet. 1977; 1: 803. - 199.
  ¹⁹ Abramsky, O. ~ Common and uncommon neurological manifestations as presenting symptoms of vitamin B12 deficiency. Journal of the American Geriatric Society. 1972; 20: 93 - 96.
• Cramps, tingling in feet and hands and later in legs, arms and face as well. “Feeling like there’s electricity running through you”, “here are ants crawling up my legs – it’s driving me crazy”. Also: a strange numb sensation in the hands and feet. Loss of function. Tremor of the hands.
  ²⁰ Blz. 34, 43, 44, 45, 55, 71, 85, 102, 103, 114, 133, 176, 189, 191 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²¹ J Clin Pharmacol 1998; 38:1151-1154. * Abramsky, O. ~ Common and uncommon neurological manifestations as presenting symptoms of vitamin B12 deficiency. Journal of the American Geriatric Society. 1972; 20: 93 - 96.
  ²² Reversible myelopathy with vitamin B12 deficiency. Senol MG, Sonmez G, Ozdag F, Saracoglu M.Department of Neurology, GATA Haydarpasa Egitim Hastanesi, Noroloji Servisi, Kadikoy, Istanbul, Turkey. mgsenol@yahoo.com; Singapore Med J. 2008 Nov;49(11):e330-2.
  ²³ Masked deficit of vitamin B12 in the patient with heterozygous beta-thalassemia and spastic paraparesis. Bilic E, Bilic E, Zagar M, Juric S.Department of Pediatric Haematology, University Hospital Centre Zagreb, Croatia. ernest.bilic@zg.htnet.hr; ta Neurol Belg. 2004 Dec;104(4):173-5.
  ²⁴ Case 30-2004 - A 37-Year-Old Woman with Paresthesias of the Arms and Legs; Peter W. Marks, M.D., Ph.D., and Lawrence R. Zukerberg, M.D.; N Engl J Med 2004; 351:1333-1341.
  ²⁵ Case 13-2012 - A 62-Year-Old Man with Paresthesias, Weight Loss, Jaundice, and Anemia; april 2012, Alberto Puig, M.D., Ph.D., Mari Mino-Kenudson, M.D., and Anand S. Dighe, M.D., Ph.D.;N Engl J Med 2012; 366:1626-1633.
• Hyperesthesia, nerve pain (neuropathic pain). Caused by damaged nerve endings. “Oversensitivity or overstimulation of the tactile nerve endings in (parts of) the skin, that can be tingling, irritating or painful. The cause can be located either in the skin (inflammation of the nerve ending for instance) or located more centrally.”
  ²⁶ Nardin RA, Amick AN, Raynor EM. Vitamin B(12) and methylmalonic acid levels in patients presenting with polyneuropathy. Muscle Nerve 2007; 36(4):532-5.
  ²⁷ Parry T.E. La Presse Medicale 1994;23(3):131-137
• Having to pee a lot, hypertonic bladder, bladder incontinence (not being able to hold your pee).
  ²⁸ Blz. 43-45, 50, 52, 55, 88, 184, 186, 202-205, 208 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁹ Rare sensory and autonomic disturbances associated with vitamin B12 deficiency. Puntambekar P, Basha MM, Zak IT, Madhavan R. J Neurol Sci. 2009 Dec 5;287(1-2):285-7.
  ³⁰ Neuropathic bladder in setting of severe vitamin B12 deficiency: a case report. Campellone JV, Bosley TM, Malloy TR. J Urol. 1995 Jul;154(1):199-200.
  ³¹ Neurological signs are common in patients with urodynamically verified "idiopathic" bladder overactivity. Neurourol Urodyn. 2002;21(1):65-70. Ahlberg J, Edlund C, Wikkelsö C, Rosengren L, Fall M.
  ³² Bladder dysfunction in subacute combined degeneration: a clinical, MRI and urodynamic study. Misra UK, Kalita J, Kumar G, Kapoor R. J Neurol. 2008 Dec;255(12):1881-8.
• Headaches
  ³³ Blz. 44 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁴ Unusual association of Arnold-Chiari malformation and vitamin B12 deficiency. Verma R, Praharaj HN. BMJ Case Rep. 2012 Jul 9;2012.
  ³⁵ VITAMIN B12 DEFICIENCY & HEADACHES. Article on www.livestrong.com.
  ³⁶ National Institutes of Health; National Heart, Mayo Clinic and Lung and Blood Institute: Pernicous Anemia, Vitamin B12 Deficiency;by Ed Garcia.Jun 14, 2011.
• Migraines
  ³⁷ Lea R, Colson N, [..], Griffiths L. The effects of vitamin supplementation and MTHFR (C677T) genotype on homocysteine-lowering and migraine disability. Pharmacogenet Genomics 2009; 19(6):422-428.
  ³⁸ Role of Magnesium, Coenzyme Q10, Riboflavin, and Vitamin B12 in Migraine Prophylaxis. "Vitamins & Hormones Volume 69. Vitamins and hormones. Bianchi, A; Salomone, S; Caraci, F; Pizza, V; Bernardini, R; Damato, C (2004).Vitamins & Hormones 69: 297-312
• Restless leg syndrome
  ³⁹ Blz. 79 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁰ B12 & RESTLESS LEGS;National Institutes of Health: Dietary Supplement Fact Sheet - Vitamin B12, 2010.
  ⁴¹ Restless legs syndrome and sleep disturbance during pregnancy: the role of folate and iron. Lee KA, Zaffke ME, Baratte-Beebe K. USA.; J Womens Health Gend Based Med. 2001 May;10(4):335-41.
  ⁴² Restless legs syndrome in the elderly, P S.T. O'Keeffe, J. Noel and J.N. Lavan, Postgrad Med J (1993) 69, 701 - 703. Ireland.
• Ataxie, coordination problems, lowered sense of position. Instable, clumsy gait, drunken gait, or even not being able to walk at all. The mobility scooter/wheelchair phase has then arrived. And with it, all kinds of adjustments (such as a stair elevator) are required in your home.
  ⁴³ Blz. 102, 278, 282 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁴ Kishimoto, Y.; Williams, M.; Moser, H.W.; Hignite, B.; Biemann, K. ~ Branched chain and odd-numbered fatty acids and aldehydes in nervous system of a patient with deranged vitamin B12 metabolism. Journal of Lipid Research. 1973: 14: 69 - 77.
  ⁴⁵ Serum vitamin B12 deficiency and hyperhomocystinemia: a reversible cause of acute chorea, cerebellar ataxia in an adult with cerebral ischemia. Shyambabu C, Sinha S, Taly AB, Vijayan J, Kovoor JM; J Neurol Sci. 2008 Oct 15;273(1-2):152-4. Department of Neurology, NIMHANS, Hosur Road, Bangalore, 560029, India.
• Dizziness
  ⁴⁶ Blz. 32, 33, 34, 55, 73, 79, 80, 186, 194, 208, 219, 222, 250, 251, 255, 257, 269 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁷ Acute presentation of dizziness in vitamin B12 deficient old patient of cardiac disease: a case report. Singh B, Arora S.; Clin Chim Acta. 2010 Dec 14;411(23-24):2104-6. Epub 2010 Aug 22.
  ⁴⁸ Serum homocysteine, vitamin B12, folic acid levels and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in vitiligo. Yasar A, Gunduz K, Onur E, Calkan M. Dis Markers. 2012;33(2):85-9.
• Unexplained falling, fractures, also: dropping objects for no reason. Or: not having the strength to get open jars.
  ⁴⁹ Gjesdal CG, Vollset SE, Ueland PM, Refsum H, Meyer HE, Grethe ST. Plasma homocysteine, folate, and vitamin B 12 and the risk of hip fracture: the hordaland homocysteine study. J Bone Miner Res 2007; 22(5):747-56.
  ⁵⁰ Rationale and design of the B-PROOF study, a randomized controlled trial on the effect of supplemental intake of vitamin B12 and folic acid on fracture incidence; van Wijngaarden JP, Dhonukshe-Rutten RA, van Schoor NM, van der Velde N, Swart KM, Enneman AW, van Dijk SC, Brouwer-Brolsma EM, Zillikens MC, van Meurs JB, Brug J, Uitterlinden AG, Lips P, de Groot LC. Department of Human Nutrition, Wageningen University, P,O, Box 8129 6700 EV Wageningen, the Netherlands. janneke.vanwijngaarden@wur.nl; BMC Geriatr. 2011 Dec 2;11:80.
  ⁵¹ Homocysteine and vitamin B12 status relate to bone turnover markers, broadband ultrasound attenuation, and fractures in healthy elderly people. Dhonukshe-Rutten RA, Pluijm SM, de Groot LC, Lips P, Smit JH, van Staveren WA.Human Nutrition, Wageningen University, Wageningen, The Netherlands. rosalierutten@yahoo.com; J Bone Miner Res. 2005 Jun;20(6):921-9. Epub 2005 Feb 7.
  ⁵² Effects of vitamin B12 on cell proliferation and cellular alkaline phosphatase activity in human bone marrow stromal osteoprogenitor cells and UMR106 osteoblastic cells. Kim GS, Kim CH, Park JY, Lee KU, Park CS. Division of Endocrinology, Asan Medical Center, Seoul, Korea; Metabolism. 1996 Dec;45(12):1443-6.
  ⁵³ Vitamin B12 deficiency in the elderly. A major contributor to falls. Nelson JM. University of Colorado Health Sciences Center, Denver, USA.  Adv Nurse Pract. 2001 Nov;9(11):39-41.
  ⁵⁴ Blz. 23, 32, 33, 44, 45, 50, 51, 56, 70, 71, 72, 73, 74, 75, 152, 186, 191, 227, 250, 251, 255, 257, 258 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
⁵⁵ Blz. 44, 45, 74, 75, 132, 154, 222 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2

• Osteoporosis (Decrease in bone mass, increasing the chance of fractures and degenerative arthritis). Decreased activity of osteoblasts (cells that generate new bone).
  ⁵⁶ van Meurs JB, Dhonukshe-Rutten RA, Pluijm SM, van der Klift M, de Jonge R, Lindemans J, de Groot LC, Hofman A, Witteman JC, van Leeuwen JP, Breteler MM, Lips P, Pols HA, Uitterlinden AG. Homocysteine levels and the risk of osteoporotic fracture. N Engl J Med 2004; 350(20):2033-41.
  ⁵⁷ Reversal of severe osteoporosis with vitamin B12 and etidronate therapy in a patient with pernicious anemia; Mary E. Melton, Michael L. Kochman Department of Internal Medicine, University of Michigan, Ann Arbor, MI USA.http://dx.doi.org/10.1016/0026-0495(94)90078-7
• Eye problems, macular degeneration
  ⁵⁸ Rochtchina E, Wang JJ, Flood VM, Mitchell P. Elevated serum homocysteine, low serum vitamin B12, folate, and age-related macular degeneration: the Blue Mountains Eye Study. Am J Ophthalmol 2007; 143(2):344-6.
  ⁵⁹ B vitamins may be "silver bullet" for age-related macular degeneration. Daily supplementation with folic acid plus vitamins B6 and B12 may reduce risk of AMD by 35-40 percent; Duke Med Health News. 2009 May;15(5):8-9.
  ⁶⁰ Elevated serum homocysteine, low serum vitamin B12, folate, and age-related macular degeneration: the Blue Mountains Eye Study. Rochtchina E, Wang JJ, Flood VM, Mitchell P. Department of Ophthalmology, Centre for Vision Research, Westmead Millennium Institute, University of Sydney, Sydney, Australia;  Am J Ophthalmol. 2007 Feb;143(2):344-6. Epub 2006 Sep 29.
  ⁶¹ Blz. 212, 235, 236 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶² Christen WG, Glynn RJ, Chew EY, et al. Folic acid, pyridoxine, and cyanocobalamin combination treatment and age-related macular degeneration in women. Arch Intern Med 2009;169:335-41.
  ⁶³ Visual failure caused by vitamin B12 deficiency optic neuropathy; A.J. Larner Int J Clin Pract, October 2004, 58, 10, 977-978
• Decreased or loss of sight
  ⁶⁴ Blz. 21, 40, 44, 45, 79 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶⁵ Christen WG, Glynn RJ, [..], Manson JE. Folic acid, pyridoxine, and cyanocobalamin combination treatment and age-related macular degeneration in women: the Women's Antioxidant and Folic Acid Cardiovascular Study. Arch Intern Med 2009; 169(4):335-41.
  ⁶⁶ Visual failure caused by vitamin B12 deficiency optic neuropathy; A.J. Larner Int J Clin Pract, October 2004, 58, 10, 977-978.
  ⁶⁷ Visual failure caused by vitamin B12 deficiency optic neuropathy.Larner AJ. Walton Centre for Neurology and Neurosurgery, Lower Lane, Fazakerley, Liverpool, UK. a.larner@thewaltoncentre.nhs.uk;
• Damage to optic nerves
  ⁶⁸ Optic atrophy in experimental vitamin B12 deficiency in monkeys. Chester EM, Agam Int J Clin Pract. 2004 Oct;58(10):977-8.anolis DP, Harris JW, Victor M, Hines JD, Kark JA.; Acta Neurol Scand. 1980 Jan;61(1):9-26
  ⁶⁹ Neuropathology of experimental vitamin B12 deficiency in monkeys. Agamanolis DP, Chester EM, Victor M, Kark JA, Hines JD, Harris JW.; Neurology. 1976 Oct;26(10):905-14.
  ⁷⁰ Blz. 101, 221 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  Causing:
• Strange vibrations in the eye, flashes of light, contracting vibrations of the eyelids (strange tics).
  ⁷¹ Encephalomyelopathy due to vitamin B12 deficiency with seizures as a predominant symptom.Matsumoto A, Shiga Y, Shimizu H, Kimura I, Hisanaga K.Department of Neurology, Miyagi National Hospital. Blz. 43, 101, 221 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2 Rinsho Shinkeigaku. 2009 Apr;49(4):179-85.
  ⁷² Downbeat nystagmus indicates cerebellar or brain-stem lesions in vitamin B12 deficiency. Mayfrank L, Thoden U.; J Neurol. 1986 Jun;233(3):145-8.
• Optical neuropathy (lessened perception of colour, blurred vision, trouble seeing in the dark, field of vision failure).
  ⁷³ Blz. 101, 102, 212, 221 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷⁴ Neuropathology of experimental vitamin B12 deficiency in monkeys. Agamanolis DP, Chester EM, Victor M, Kark JA, Hines JD, Harris JW; Neurology. 1976 Oct;26(10):905-14.
• Damage to optic nerve, inflammation, paralysis, infection or atrophy.
  ⁷⁵ Paralysis of upward gaze as a presenting symptom of vitamin B12 deficiency.Sandyk R. Eur Neurol. 1984;23(3):198-200.
• Hearing disorders decreased hearing, distorted hearing.
  ⁷⁶ Houston DK, Johnson MA, Nozza RJ, Gunter EW, Shea KJ, Cutler GM, Edmonds JT. Age-related hearing loss, vitamin B-12, and folate in elderly women. American Journal of Clinical Nutrition 1999; 69:564-571
  ⁷⁷ Gopinath B, Flood VM, [..], Mitchell P. Serum Homocysteine and Folate Concentrations Are Associated with Prevalent Age-Related Hearing Loss. J Nutr 2010; 140(8):1469-74.
  ³²⁶ Houston DK, Johnson MA, Nozza RJ, Gunter EW, Shea KJ, Cutler GM, Edmonds JT. Age-related hearing loss, vitamin B-12, and folate in elderly women. American Journal of Clinical Nutrition 1999; 69:564-571
• Tinnitus
  ⁷⁸ Blz. 211 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷⁹ Vitamine B12 Tekort Oorzaak Oorsuizen? www.optimalegezondheid.com/vitamine-b12-tekort-en-oorsuizen
  ⁸⁰ http://mens-en-gezondheid.infonu.nl/aandoeningen/61690-tinnitus-oorsuizen-oor-geluiden-genezen-en-behandeling.html - http://mens-en-gezondheid.infonu.nl/aandoeningen/64994-vitamine-b12-tekort-symptomen-klachten-oorzaak-voeding.html
  ⁸¹ Everdingen, Jannes J.E. van, (hoofdredactie): Het medisch handboek; Kosmos-Z&K Uitgevers, Utrecht/Antwerpen, vijfde volledig herziene druk 2006.
• Joint pain, muscle soreness, especially in the hips, but also in the wrists and other joints. Symptoms partly resemble fibromyalgia. The patient complains about a stiff and heavy feeling in the legs. There is an unstable gait and muscle soreness is a lot worse than before. Leg pain while walking. There are often there problems with fine motor skills as well (fastening small buttons or getting small coins from a wallet are difficult).
  ⁸² Blz. 40, 51, 52 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁸³ The relationship between serum trace elements, vitamin B12, folic acid and clinical parameters in patients with myofascial pain syndrome. Okumus M, Ceceli E, Tuncay F, Kocaoglu S, Palulu N, Yorgancioglu ZR. Department of First Physical Medicine and Rehabilitation, Ministry of Health Ankara Training and Research Hospital, Ankara, Turkey. drmuyesser@hotmail.com.; J Back Musculoskelet Rehabil. 2010;23(4):187-91.
• Lower back pain
  ⁸⁴ Vitamin B12 in low back pain: a randomised, double-blind, placebo-controlled study. Mauro GL, Martorana U, Cataldo P, Brancato G, Letizia G. Eur Rev Med Pharmacol Sci. 2000 May-Jun;4(3):53-8.
  ⁸⁵ Case 46-1969 - Eighty-Year-Old Woman with Back Pain and Abnormal Immunoglobulins, William H. Baker, and Benjamin Castleman;N Engl J Med 1969; 281:1118-1126.
  ⁸⁶ Case 12-1990 - A 21-Year-Old Man with Progressive Gastrointestinal Stasis, Hepatomegaly, and a Neurologic Disorder, Cave D.R. and Compton C.C.N Engl J Med 1990; 322:829-841.
• Strange feeling in the feet feeling like you’re walking on felt, cotton balls or cushions; distorted surface sensation. Hanging foot.
  ⁸⁷ Recovery of neurologic dysfunction with early intervention of vitamin B12. Ahmed A, Kothari MJ. Penn State College of Medicine, Hershey Medical Center, Department of Neurology, Hershey, PA 17033, USA; J Clin Neuromuscul Dis. 2010 Jun;11(4):198-202.
  ⁸⁸ Blz. 80, 88 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Walking disorders
  ⁸⁹ Neurologic symptoms as the first manifestation of Addison-Biermer disease.Rzepecki P, Nowosielski J, Kotowicz J, Betiuk B. V Kliniki Chorób Wewnetrznych IMW CSK WAM, Warszawie; Wiad Lek. 1994 Aug;47(15-16):632-4.
  ⁹⁰ Reversible myelopathy with vitamin B12 deficiency. Senol MG, Sonmez G, Ozdag F, Saracoglu M. Department of Neurology, GATA Haydarpasa Egitim Hastanesi, Noroloji Servisi, Kadikoy, Istanbul, Turkey. mgsenol@yahoo.com; Singapore Med J. 2008 Nov;49(11):e330-2.
  ⁹¹ Blz. 44, 51, 73, 85, 88, 222 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Numb feeling in limbs, quote: “Sensation of the surface in the lower body and the legs is greatly decreased or almost disappeared.”
  ⁹² Serial nerve conduction studies in vitamin B12 deficiency-associated polyneuropathy. Huang CR, Chang WN, Tsai NW, Lu CH. Department of Neurology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, No. 123, Tai-Pei Rd, Niao-Song Township, Kaohsiung, 833, Taiwan; Neurol Sci. 2011 Feb;32(1):183-6. Epub 2010 Oct 2.
  ⁹³ Blz. 70, 77, 84, 88, 102, 103, 105, 114, 133, 171, 176, 178, 184, 188, 191 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Weakening in the legs, trunk or other part of the body (even the voice).
  ⁹⁴ A case of subacute combined degeneration with normal serum vitamin B12 level.Nagaishi A, Takashima H, Fukuda Y, Kuroda Y.Department of Internal Medicine, Sasebo City General Hospital.; Rinsho Shinkeigaku. 2003 Sep;43(9):552-5.
  ⁹⁵ A case of vitamin B12 deficiency with broad neurologic disorders and canities. Katsuoka H, Watanabe C, Mimori Y, Nakamura S. Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan; No To Shinkei. 1997 Mar;49(3):283-6.
  ⁹⁶ Vitamin B12 deficiency: an unusual cause of vocal fold palsy.Green R, Kara N, Cocks H. UK. richardgreen81@hotmail.co.uk; J Laryngol Otol. 2011 Dec;125(12):1309-11. Epub 2011 Jul 27.
  ⁹⁷ Blz. 32-34, 42-44, 47, 71, 72, 79-81, 83, 85, 90, 126, 137, 171, 186, 193, 211, 217, 218, 222, 228, 234, 235, 244, 250, 251, 255, 263, 281, 287, 291 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Paralysis
  ⁹⁸ Encephalomyelopathy due to vitamin B12 deficiency with seizures as a predominant symptom. Matsumoto A, Shiga Y, Shimizu H, Kimura I, Hisanaga K. Department of Neurology, Miyagi National Hospital; Rinsho Shinkeigaku. 2009 Apr;49(4):179-85.
  ⁹⁹ Paralysis and pernicious anemia in a young woman.Matrana MR, Gauthier C, Lafaye KM. Internal Medicine Residency Program, Ochsner Clinic Foundation, New Orleans, LA, USA; J La State Med Soc. 2009 Jul-Aug;161(4):228-32.
  ¹⁰⁰ Recurrent facial palsy, primary Gougerot-Sjögren's syndrome and vitamin B12 deficiency.Rousso E, Noel E, Brogard JM, Blicklé JF, Andrès E. Service de médecine interne, diabète et maladies métaboliques de la Clinique médicale B, Hôpitaux universitaires de Strasbourg; Presse Med. 2005 Jan 29;34(2 Pt 1):107-8.
  ¹⁰¹ Difficulties in the diagnosis in the case of subacute paraplegia in a woman with Addison-Biermer disease. Szupień E, Ositek B, Pniewski J. Klinika Neurologii, Centralny Szpital Kliniczny MSWiA w Warszawie, Warsaw, Poland; Neurol Neurochir Pol. 2004 Sep-Oct;38(5):431-6.
  ¹⁰² Neurologic symptoms as the first manifestation of Addison-Biermer disease.Rzepecki P, Nowosielski J, Kotowicz J, Betiuk B. V Kliniki Chorób Wewnetrznych IMW CSK WAM, Warszawie; Wiad Lek. 1994 Aug;47(15-16):632-4.
  ¹⁰³ Inborn error of vitamin B12 metabolism: a treatable cause of childhood dementia/paralysis. Al Essa M, Sakati NA, Dabbagh O, Joshi S, Al Jishi EA, Rashed MS, Powe JE, Ozand PT. Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia; J Child Neurol. 1998 May;13(5):239-43.
  ¹⁰⁴ Paralysis and pernicious anemia in a young woman.Matrana MR, Gauthier C, Lafaye KM. Internal Medicine Residency Program, Ochsner Clinic Foundation, New Orleans, LA, USA; J La State Med Soc. 2009 Jul-Aug;161(4):228-32  
  ¹⁰⁵ Blz. 25, 40, 43, 44, 72, 79, 81, 109, 171, 190, 257 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Complaints of aging, such as forgetfulness, tiredness, depression, shaking limbs, cardiac arrhythmia, balancing problems, falling (and fractures), osteoporosis, disabled sight and hearing, may often be connected to a chronic vitamin B12 deficiency.
  ¹⁰⁶ Walker JG, Batterham PJ, [..], Christensen H. Oral folic acid and vitamin B-12 supplementation to prevent cognitive decline in community-dwelling older adults with depressive symptoms--the Beyond Ageing Project: a randomized controlled trial. Am J Clin Nutr 2012; 95(1):194-203.
  ¹⁰⁷ Skarupski KA, Tangney C, [..], Morris MC. Longitudinal association of vitamin B-6, folate, and vitamin B-12 with depressive symptoms among older adults over time. Am J Clin Nutr 2010; 92(2):330-5
  ¹⁰⁸ Tangney CC, Aggarwal NT, [..], Morris MC. Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology 2011; 77(13):1276-82. -7.
  ¹⁰⁹ Dimopoulos N, Piperi C, Salonicioti A, Psarra V, Gazi F, Papadimitriou A, Lea RW, Kalofoutis A. Correlation of folate, vitamin B12 and homocysteine plasma levels with depression in an elderly Greek population. Clin Biochem 2007; 40(9-10):604-8
  ¹¹⁰ Louwman MWJ et al. Signs of impaired cognitive function in adolescents with marginal cobalamin status. Am J Clin Nutr 2000;72:762-769.
  ¹¹¹ Houston DK, Johnson MA, Nozza RJ, Gunter EW, Shea KJ, Cutler GM, Edmonds JT. Age-related hearing loss, vitamin B-12, and folate in elderly women. American Journal of Clinical Nutrition 1999; 69:564-571.
  ¹¹² Stott D.J. et al. Prevalence and haemopoietic effects of low serum vitamin B12 levels in geriatric medical patients. British Journal of Nutrition 1997;78:57-63.
  ¹¹³ Role of cobalamin intake and atrophic gastritis in mild cobalamin deficiency in older Dutch subjects; Dieneke ZB van Asselt, Lisette CPGM de Groot, Wija A van Staveren, Henk J Blom, Ron A Wevers, Izak Biemond, and Willibrord HL Hoefnagels Am J Clin Nutr 1998;68:328-34.
  ¹¹⁴ Functional vitamin B12 deficiency and Alzheimer disease A. McCaddon, MRCGP; B. Regland, MD, PhD; P. Hudson, MSc; and G. Davies, MSc Neurology 2002;58:1395-1399;
  ¹¹⁵ Clinical significance of low cobalamin levels in older hospital patient; Dieneke Z. van Asselt , Henk J. Blom , Richard Zuiderent , Ron A. Wevers, Cornelis Jakobs , Wim J. van den Broek , Cornelis B. Lamers , Frans H. Corstens , Willibrord H. Hoefnagels The Netherlands Journal of Medicine 2000;57:41-49;
  ¹¹⁶ Joosten, E.; e.a. ~ Vitamin B12 (cobalamine) gebrek bij bejaarden. Nederlands Tijdschrift voor de Geneeskunde. 1990; 134 (13): 652 - 656.
  ¹¹⁷ McRea, Thomas D.; Freedman Michael L. ~ Why vitamin B12 deficiency should be managed aggressively. Geriatrics. November 1989; 44 (2): 70 - 79.
  ¹¹⁸ Schulman, R. ~ A survey of vitamin B12 deficiency in an elderly psychiatric population. British Journal of Psychiatry. 1967a; 113: 241 - 251.
  ¹¹⁹ Relationship between vitamin B12 and sensory and motor peripheral nerve function in older adults. Leishear K, Boudreau RM, Studenski SA, Ferrucci L, Rosano C, de Rekeneire N, Houston DK, Kritchevsky SB, Schwartz AV, Vinik AI, Hogervorst E, Yaffe K, Harris TB, Newman AB,  Strotmeyer ES; Health, Aging and Body Composition Study. J Am Geriatr Soc. 2012 Jun;60(6):1057-63.
  ¹²⁰ [Vitamin B12 and folic acid deficiency in the population over 65 years: A descriptive study.]Vazquez-Pedrazuela MD, Canton-Alvarez MB, de la Fuente-Hontañon MD, Soloaga-Morales A, Collazos-Del Castillo JM, Sertal-Parcero R. Rev Esp Geriatr Gerontol. 2012 May 28.
  ¹²¹ Vitamin B12 deficiency in Australian residential aged care facilities. Mirkazemi C, Peterson GM, Tenni PC, Jackson SL. J Nutr Health Aging. 2012 Mar;16(3):277-80.
  ¹²² The neuropsychiatry of vitamin B12 deficiency in elderly patients. Lachner C, Steinle NI, Regenold WT. J Neuropsychiatry Clin Neurosci. 2012 Dec 1;24(1):5-15. Review.
  ¹²³ Vitamin B12 supplementation improves heart rate variability in healthy elderly Indian subjects. Sucharita S, Thomas T, Antony B, Vaz M. Auton Neurosci. 2012 May 21;168(1-2):66-71.
  ¹²⁴ An investigation of vitamin B12 deficiency in elderly inpatients in neurology department. Wang YH, Yan F, Zhang WB, Ye G, Zheng YY, Zhang XH, Shao FY.Department of Neurology, Shanghai Punan hospital, Shanghai 200125, China. yhwangch@sina.com; Neurosci Bull. 2009 Aug;25(4):209-15.
  ¹²⁵ Garcia, Angela, et al. Is low-dose oral cobalamin enough to normalize cobalamin function in older people? Journal of the American Geriatrics Society, Vol. 50, August 2002, pp. 1401-04.
  ¹²⁶ Slowly progressive type 1 diabetes mellitus associated with vitiligo vulgaris, chronic thyroiditis, and pernicious anemia. Suzuki C, Hirai Y, Terui K, Kohsaka A, Akagi T, Suda T. Department of Endocrinology, Aomori Prefectural Central Hospital, Aomori.; Intern Med. 2004 Dec;43(12):1183-5.
  ¹²⁷ Relationship of vitamin B12 deficiency with incontinence in older people.  Rana S, D'Amico F, Merenstein JH. J Am Geriatr Soc 1998;46:931-2.
  ¹²⁸ Studies on vitamin B12 status in the elderly--prophylactic and therapeutic consequences.Loew D, Wanitschke R, Schroedter A.Institute of Clinical Pharmacology, Johann Wolfgang Goethe University, Frankfurt, Germany; Int J Vitam Nutr Res. 1999 May;69(3):228-33.
  ¹²⁹ Oral folic acid and vitamin B-12 supplementation to prevent cognitive decline. Feng L.Folic acid and vitamin B-12 supplementation to prevent cognitive decline in community-dwelling older adults with depressive symptoms--the Beyond Ageing Project: a randomized controlled trial. [Am J Clin Nutr. 2012; Am J Clin Nutr. 2012 May;95(5):1289-90
• Heartburn and other stomach complaints
  ¹³⁰ Dharmarajan TS, Kanagala MR, Murakonda P, Lebelt AS, Norkus EP. Do acid-lowering agents affect vitamin B12 status in older adults? J Am Med Dir Assoc 2008; 9(3):162-7.
  ¹³¹ Morphological features and secretory gastric function in patients with chronic gastritis against the background of B12 deficiency anemia. Vorob'ev SA; Eksp Klin Gastroenterol. 2006;(4):11-6, 114.
  ¹³² Cobalamin (Vitamin B12) deficiency: is it a problem for our aging population and is the problem compounded by drugs that inhibit gastric acid secretion? Kapadia C.; J Clin Gastroenterol. 2000 Jan;30(1):4-6.
• Early aging
  ¹³³ Tangney CC, Aggarwal NT, [..], Morris MC. Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology 2011; 77(13):1276-82.
  ¹³⁴ Walker JG, Batterham PJ, [..], Christensen H. Oral folic acid and vitamin B-12 supplementation to prevent cognitive decline in community-dwelling older adults with depressive symptoms--the Beyond Ageing Project: a randomized controlled trial. Am J Clin Nutr 2012; 95(1):194-203.
  ¹³⁵ van Asselt DZ, Pasman JW, van Lier HJ, Vingerhoets DM, Poels PJ, Kuin Y, Blom HJ, Hoefnagels WH. Cobalamin supplementation improves cognitive and cerebral function in older, cobalamin-deficient persons. J Gerontol A Biol Sci Med Sci 2001; 56(12):M775-9.
  ¹³⁶ Herzlich BC et al. Relationship among homocyst(e)ine, vitamin B-12 and cardiac disease in the elderly: association between vitamine B12 deficiency and decreased left ventricular ejection fraction. Journal of Nutrition 1996;126:1249S-1253.
  ¹³⁷ Developmental regression as an early manifestation of vitamin B12 deficiency. Sadowitz, P.D.; e.a. ~ Clinical Pediatrics. 1986; 25: 369 - 371; J Hum Lact December 1, 1986 2: 129-132
  ¹³⁸ Geriatrics. 1989 Nov;44(11):70-3, 76, 79.
  ¹³⁹ Why vitamin B12 deficiency should be managed aggressively. McRae TD, Freedman ML. Department of Internal Medicine, New York University School of Medicine; Geriatrics. 1989 Nov;44(11):70-3, 76, 79.
  ¹⁴⁰ Vitamin B12 status and rate of brain volume loss in community-dwelling elderly. Vogiatzoglou A, Refsum H, Johnston C, Smith SM, Bradley KM, de Jager C, Budge MM, Smith AD. Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Rd., Oxford OX1 3QX, UK. anna.vogiatzoglou@dpag.ox.ac.uk; Neurology. 2008 Sep 9;71(11):826-32.
  ¹⁴¹ Low vitamin B-12 status and risk of cognitive decline in older adults. Clarke R, Birks J, Nexo E, Ueland PM, Schneede J, Scott J, Molloy A, Evans JG. University of Oxford, . robert.clarke@ctsu.ox.ac.uk; Am J Clin Nutr. 2007 Nov;86(5):1384-91.
  ¹⁴² Normalization of low vitamin B12 serum levels in older people by oral treatment.Verhaeverbeke I, Mets T, Mulkens K, Vandewoude M.; J Am Geriatr Soc. 1997 Jan;45(1):124-5.
  ¹⁴³ Early normalization of low vitamin B12 levels by oral cobalamin therapy in three older patients with pernicious anemia; Kaltenbach G, Noblet-Dick M, Barnier-Figue G, Berthel M, Kuntzmann F, Andres E.; J Am Geriatr Soc. 2002 Nov;50(11):1914-5.
  ¹⁴⁴ Why vitamin B12 deficiency should be managed aggressively. McRae TD, Freedman ML. New York University School of Medicine;Epub 2008 Nov 5. Geriatrics. 1989 Nov;44(11):70-3, 76, 79.
  ³³³ Blz.164 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Alzheimer’s (including early-onset); a daily dose of vitamin B12 lowers the risk of early dementia and Alzheimer’s by 30 percent, according to research published in the American Journal of Clinical Nutrition. Researchers followed 1648 seniors between the ages of 65 and 90 over a period of 10 years. Vitamin B12 has the property to drastically lower a high and harmful homocysteine level. This decreases the amount of cardiovascular damage and brain damage with increasing age.
  ¹⁴⁵ Robert Clarke, J. Birks, E. Nexo, P.M. Ueland, J. Schneede, J. Scott, A. Molloy and J. Grimley Evans. Low vitamin B-12 status and risk of cognitive decline in older adults November 2007, Volume 86, Number 5, Pages 1384-1391 - American Journal of Clinical Nutrition
  ¹⁴⁶ Blz. 17, 21, 25, 41, 43, 47, 50, 60, 61, 63-67, 69, 77, 105, 132, 212, 226, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁴⁷ Cognitive and clinical outcomes of homocysteine-lowering B-vitamin treatment in mild cognitive impairment: a randomized controlled trial. de Jager CA, Oulhaj A, [..], Smith AD. Int J Geriatr Psychiatry 2011 Jul 21.
  ¹⁴⁸ Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study; Hooshmand B, Solomon A, [..], Kivipelto M.; Neurology 2010; 75(16):1408-14.
  ¹⁴⁹ Vitamin B12 and folate in relation to the development of Alzheimer’s disease; H-X. Wang, Å. Wahlin, H. Basun, J. Fastbom, B. Winblad, and L. Fratiglioni; Neurology May 8, 2001 56:1188-1194.
  ¹⁵⁰ Is metabolic evidence for vitamin B-12 and folate deficiency more frequent in elderly patients with Alzheimer's disease? Joosten E et al. Journal of Gerontology: Medical Sciences 1997;52A:M76-M79.
  ¹⁵¹ Low serum vitamin B12 in Alzheimer-type dementia. Cole, M.; e.a. ~ Age Ageing. 1984; 13: 101 - 105.
  ¹⁵² Vitamin B(12) and folate in relation to the development of Alzheimer's disease. Wang HX, Wahlin A, Basun H, Fastbom J, Winblad B, Fratiglioni L.Stockholm. Huixin.wang@phs.ki.se; Neurology. 2001 May 8;56(9):1188-94.
  ¹⁵³ Homocysteine and holo-transcobalamin and the risk of dementia and Alzheimers disease: a prospective study. Eur J Neurol. 2009 Jul;16(7):808-13. Epub 2009 Apr 21. Kivipelto M, Annerbo S, Hultdin J, Bäckman L, Viitanen M, Fratiglioni L, Lökk J.
  ¹⁵⁴ A Specific Multi-Nutrient Diet Reduces Alzheimer-Like Pathology in Young Adult AβPPswe/PS1dE9 Mice. Broersen LM, Kuipers AA, Balvers M, van Wijk N, Savelkoul PJ, de Wilde MC, van der Beek EM, Sijben JW, Hageman RJ, Kamphuis PJ, Kiliaan AJ.; Wageningen, Holland; J Alzheimers Dis. 2012 Aug 22.
  ¹⁵⁵ Homocysteine, vitamin B12, and folic acid levels in Alzheimer's disease, mild cognitive impairment, and healthy elderly: baseline characteristics in subjects of the Australian Imaging Biomarker Lifestyle study.Faux NG, Ellis KA, Porter L, Fowler CJ, Laws SM, Martins RN, Pertile KK, Rembach A, Rowe CC, Rumble RL, Szoeke C, Taddei K, Taddei T, Trounson BO, Villemagne VL, Ward V, Ames D, Masters CL, Bush AI; Australia; J Alzheimers Dis. 2011;27(4):909-22.
  ³²⁷ Folate/vitamin-B12 prevents chronic hyperhomocysteinemia-induced tau Hyperphosphorylation and memory deficits in aged rats;Wei W, Liu YH, Zhang CE, Wang Q, Wei Z, Mousseau DD, Wang JZ, Tian Q, Liu GP. China.; J Alzheimers Dis. 2011;27(3):639-50.
• Parkinson’s (including early-onset) Note: The use of the drug Levodopa, often prescribed to Parkinson’s patients, may lead to a vitamin B12 deficiency.
  ¹⁵⁶ Neurology [2011] Nov 2 (Y.A.Rajabally, J.Martey)
  ¹⁵⁷ Blz. 17, 21, 25, 59, 69, 76, 79, 81, 82, 96 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁵⁸ Dos Santos EF, Busanello EN, [..], Wajner M. Evidence that folic acid deficiency is a major determinant of hyperhomocysteinemia in Parkinson's disease. Metab Brain Dis 2009; 24(2):257-69.
  ¹⁵⁹ Dietary intake of folate, vitamin B6, vitamin B12 and riboflavin and risk of Parkinson's disease: a case-control study in Japan.Murakami K, Miyake Y, Sasaki S, Tanaka K, Fukushima W, Kiyohara C, Tsuboi Y, Yamada T, Oeda T, Miki T, Kawamura N, Sakae N, Fukuyama H, Hirota Y, Nagai M; Fukuoka Kinki Parkinson's Disease Study Group; Br J Nutr. 2010 Sep;104(5):757-64. Epub 2010 Mar 26.
  ¹⁶⁰ Vitamin B12-impaired metabolism produces apoptosis and Parkinson phenotype in rats expressing the transcobalamin-oleosin chimera in substantia nigra. Orozco-Barrios CE, Battaglia-Hsu SF, Arango-Rodriguez ML, Ayala-Davila J, Chery C, Alberto JM, Schroeder H, Daval JL, Martinez-Fong D, Gueant JL. Department of Physiology, Biophysics and Neuroscience, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Mexico City, Mexico; PLoS One. 2009 Dec 21;4(12):e8268.
  ¹⁶¹ Is the deficiency of vitamin B12 related to oxidative stress and neurotoxicity in Parkinson's patients? Qureshi GA, Qureshi AA, Devrajani BR, Chippa MA, Syed SA.Medical Research Centre, Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan. ghulamali48@hotmail.com; CNS Neurol Disord Drug Targets. 2008. Feb;7(1):20-7.
  ¹⁶² Folate and vitamin B12 levels in levodopa-treated Parkinson's disease patients: their relationship to clinical manifestations, mood and cognition.Triantafyllou NI, Nikolaou C, Boufidou F, Angelopoulos E, Rentzos M, Kararizou E, Evangelopoulos ME, Vassilopoulos D. Department of Neurology, Aeginition Hospital, Athens University Medical School, Athens, Greece; Parkinsonism Relat Disord. 2008;14(4):321-5. Epub 2007 Dec 4.
  ¹⁶³ Homocysteine and Parkinson's disease: a dangerous liaison? Martignoni E, Tassorelli C, Nappi G, Zangaglia R, Pacchetti C, Blandini F. IRCCS S. Maugeri Foundation, Scientific Institute of Veruno, Via per Revislate 13, 28010 Veruno (NO), Italy. emilia.martignoni@libero.it; J Neurol Sci. 2007 Jun 15;257(1-2):31-7. Epub 2007 Mar 1.
  ¹⁶⁴ Case of acute parkinsonism of the infant treated with vitamin B12. PRIOLISI A.; Pediatria (Napoli). 1959 Mar-Apr;67(2):325-33.
  ¹⁶⁵ Vitamin B12-impaired metabolism produces apoptosis and Parkinson phenotype in rats expressing the transcobalamin-oleosin chimera in substantia nigra.Orozco-Barrios CE, Battaglia-Hsu SF, Arango-Rodriguez ML, Ayala-Davila J, Chery C, Alberto JM, Schroeder H, Daval JL, Martinez-Fong D, Gueant JL. PLoS One. 2009 Dec 21;4(12):e8268.

Cardiovascular problems

A vitamin B12 deficiency leads to elevated homocysteine values. Elevated homocysteine values are a large risk factor for cardiovascular disease (comparable to high cholesterol).

• Pernicious anaemia
  Wikipedia: “Pernicious anaemia is a type of macrocytic anaemia. This means red blood cells are enlarged. Vitamin B12, one of the essential parts for the synthesis of haemoglobin, is missing. Absorption of vitamin B12 takes place in the last part of the small intestine. Before this process can take place, vitamin B12 has to be attached to the intrinsic factor, which is produced by the stomach wall. Because of an autoimmune reaction against the stomach’s parietal cells, the production of intrinsic factor is disrupted and vitamin B12 cannot be absorbed by the body”.
  ¹⁶⁶ Wikipedia: http://nl.wikipedia.org/wiki/Pernicieuze_anemie
  ¹⁶⁷ Blz. 58, 85-86, 137, 152, 192, 209, 217, 221, 226, 282, 284 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁶⁸ Restoration of decreased suppressor cells by vitamin B12 therapy in a patient with pernicious anemia. Kubota K, Arai T, Tamura J, Shirakura T, Morita T.; Am J Hematol. 1987 Feb;24(2):221-3.
  ¹⁶⁹ Stopeck, A. Links Between Helicobacter pylori Infection, Cobalamin Deficiency, and Pernicious Anemia. Arch Intern Med. 2000; 160:1349-1353
  ¹⁷⁰ Lebdetter, R.B.; Del Pozo, L. ~ Severe megaloblastic anemia due to nutritional vitamin B12 deficiency. Acta Haematologica. 1969; 42: 247 - 253.
  ¹⁷¹ Lederle, Frank A. ~ Oral cobalamine for pernicious anemia: medicine's best kept secret. JAMA. 1991; 265 (1): 94 - 5.
  ¹⁷² Linnell, J.C.; e.a. ~ Tissue distribution of coenzyme and other forms of vitamin B12 in control subjects and patients with pernicious anaemia. Clinical Science and Molecular Medicine. 1974b; 46: 163 - 172.
  ¹⁷³ Berlin, Ragnar; Berlin, Hans; Brante, Gunnar ~ Oral treatment of pernicious anemia with high doses of vitamin B12 without intrinsic factor. Acta Medica Scandinavica. 1968; 184: 247 - 258.
  ¹⁷⁴ Wokes, Frank ~ Anemia and vitamin B12 deficiency. Proceedings of the Nutrition Society. 1956; 15: 134 - 141.
  ¹⁷⁵ Woltman H.W. ~ The mental changes associated with pernicious anemia. American Journal of Medicine. 1924; 80: 435 - 449.
  ¹⁷⁶ Woltman H.W. ~ The nervous symptoms in pernicious anemia: an analysis of one hundred and fifty cases. American Journal of Medicine. 1919; 157: 400 - 409.
  ¹⁷⁷ Berlin, Ragnar; Berlin, Hans; Brante, Gunnar; Pilbrant, Ake ~ Vitamin B12 stores during oral treatment and parenteral treatment of pernicious anemia. Acta Medica Scandinavica. 1978; 204: 81 - 84.
  ¹⁷⁸ Pollycove, M.; e.a. ~ Pernicious anemia due to dietary deficiency of vitamin B12. New England Journal of Medicine. 1956; 255: 164 - 169.  
  ¹⁷⁹ Effectiveness of oral vitamin B12 therapy for pernicious anemia and vitamin B12 deficiency anemia.Takasaki Y, Moriuchi Y, Tsushima H, Ikeda E, Koura S, Taguchi J, Fukushima T, Tomonaga M, Ikeda S.Japan; Rinsho Ketsueki. 2002 Mar;43(3):165-9.
  ¹⁸⁰  Biermer's disease and auto-immune haemolytic anaemia. Nafil H, Tazi I, Mahmal L. Ann Biol Clin (Paris). 2012 Aug 1;70(4):480-482.
  ¹⁸¹ Clinical spectrum and diagnosis of cobalamin deficiency. Stabler SP, Allen RH, Savage DG, Lindenbaum J. Department of Medicine, University of Colorado Health Sciences Center, Denver 80262; Blood. 1990 Sep 1;76(5):871-81.
  ³²⁸ Reisner, Edward H. ~ Oral treatment of pernicious anemia with vitamin B12 without intrinsic factor. New England Journal of Medicine. 1955; 253: 502 - 506.
• Enlarged spleen or liver
  ¹⁸² Severe vitamin B12 deficiency in an exclusively breastfed 5-month-old Italian infant born to a mother receiving multivitamin supplementation during pregnancy. Guez S, Chiarelli G, Menni F, Salera S, Principi N, Esposito S. Pediatric Clinic 1, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy. susanna.esposito@unimi.it; BMC Pediatr. 2012 Jun 24;12:85. doi: 10.1186/1471-2431-12-85.
  ¹⁸³ Severe vitamin B12 deficiency resulting in pancytopenia, splenomegaly and leukoerythroblastosis. Halfdanarson TR, Walker JA, Litzow MR, Hanson CA.Department of Internal Medicine, Division of Hematology, Mayo Clinic College of Medicine, Rochester, MN, USA. thorvardur-halfdanarson@uiowa.edu; Eur J Haematol. 2008 May;80(5):448-51. Epub 2008 Jan 23.
  ³³⁴ Blz. 44 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Thyroid disorders
  ¹⁸⁴ Prevalence and evaluation of B12 deficiency in patients with autoimmune thyroid disease.Ness, Abramof R, Nabriski DA, Braverman LE, Shilo L, Weiss E, Reshef T, Shapiro MS, Shenkman L.; Am J Med Sci 2006; 332(3):119-22.
  ¹⁸⁵ The role of vitamins in the prevention and treatment of thyroid disorders. Sworczak K, Wiśniewski P. Poland. ksworczak@gumed.edu.pl; Endokrynol Pol. 2011;62(4):340-4.Vitamin B12 deficiency common in primary hypothyroidism. Jabbar A, Yawar A, Waseem S, Islam N, Ul Haque N, Zuberi L, Khan A, Akhter J.; Pakistan; J Pak Med Assoc. 2008 May;58(5):258-61.
  ¹⁸⁶ Vitamin B12 deficiency neurological syndromes: correlation of clinical, MRI and cognitive evoked potential. Kalita J, Misra UK., India. jayanteek@yahoo.com; J Neurol. 2008 Mar;255(3):353-9. Epub 2008 Mar 20.
  ¹⁸⁷ Prevalence of pernicious anaemia in patients with Type 1 diabetes mellitus and autoimmune thyroid disease.Perros P, Singh RK, Ludlam CA, Frier BM.; UK.; Perros@ncl.ac.uk; Diabet Med. 2000 Oct;17(10):749-51.
  ¹⁸⁸ Anemia in hypothyroidism.Antonijević N, Nesović M, Trbojević B, Milosević R.; Croatian; Med Pregl. 1999 Mar-May;52(3-5):136-40.
  ³²⁹ Prevalence and evaluation of B12 deficiency in patients with autoimmune thyroid disease,Ness-Abramof R, Nabriski DA, Braverman LE, Shilo L, Weiss E, Reshef T, Shapiro MS, Shenkman L., Israel; Ness@clalit.org.il; Am J Med Sci. 2006 Sep;332(3):119-22.
  ⁵⁴² American Journal of the Medical Sciences. 332(3):119-122, September 2006, Ness-Abramof, Rosane MD; Nabriski, Dan A. MD; Braverman, Lewis E. MD; Shilo, Lotan MD; Weiss, Eliahu MSc; Reshef, Tamar MSc; Shapiro, Menachem S. MD; Shenkman, Louis MD.
  ⁵⁴³ Dissociation of the intrinsic factor--vitamin B12 complex by bile: contributing factor to B12 malabsorption in pancreatic insufficiency. Cotter R, Rothenberg SP, Weiss JP.; Scand J Gastroenterol. 1979;14(5):545-50.
• Haematological disorders: enlarged red blood cells (macrocytes); hypersegmented neutrophil granulocytes; ovalocytosis.
  ¹⁸⁹ Blz. 34, 46, 55, 108, 197 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁹⁰ Al-Momen AKJ. Diminished vitamin B12 levels in patients with severe sickle cell disease. Journal of Internal Medicine 1995;237:551-555.
  ¹⁹¹ Subacute combined spinal cord degeneration and pancytopenia secondary to severe vitamin B12 deficiency. Cabrerizo-García JL, Sebastián-Royo M, Montes N, Zalba-Etayo B.Internal Medicine Service, Defense General Hospital, Zaragoza, Spain; Sao Paulo Med J. 2012;130(4):259-62.
  ¹⁹² Vitamin B12 deficiency--a major cause of megaloblastic anaemia in patients attending a tertiary care hospital. Iqbal SP, Kakepoto GN, Iqbal SP.Department of Pathology and Microbiology, Aga Khan University, Karachi, Pakistan; J Ayub Med Coll Abbottabad. 2009 Jul-Sep;21(3):92-4.
  ¹⁹³ Vitamin B12 deficiency is the primary cause of megaloblastic anaemia in Zimbabwe. Savage D, Gangaidzo I, Lindenbaum J, Kiire C, Mukiibi JM, Moyo A, Gwanzura C, Mudenge B, Bennie A, Sitima J, et al.Department of Haematology, University of Zimbabwe, Harare; Br J Haematol. 1994 Apr;86(4):844-50.
• Macrocytosis (enlarged red blood cells).
  ¹⁹⁴ Blz. 18, 19, 34, 42, 45, 57, 104, 112, 116, 137, 152, 179, 191, 192, 195, 197, 209, 221, 222, 223, 226, 256, 262, 268, 269, 272, 277, 279, 282 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁹⁵ Neuropsychiatric disorders caused by cobalamin deficiency in the absence of anemia or macrocytosis; Lindenbaum J, Healton EB, Savage DG, Brust JCM, Garrett ER, Podell ER, et al. N Eng J Med 1988;318:1720-8.
  
• Blood clots
  ¹⁹⁶ Blz. 44, 45, 46, 73, 76, 119, 121, 128, 131, 132, 137, 138, 156 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ¹⁹⁷ Bleie O, Strand E, [..], Nygård OK. Coronary blood flow in patients with stable coronary artery disease treated long term with folic acid and vitamin B12. Coron Artery Dis 2011; 22(4):270-8
  ¹⁹⁸ Omar S, Ghorbel IB, Feki H, Souissi M, Feki M, Houman H, Kaabachi N. Hyperhomocysteinemia is associated with deep venous thrombosis of the lower extremities in Tunisian patients. Clin Biochem 2007; 40(1-2):41-5
• Cardiovascular problems
  ¹⁹⁹ Quinlivan EP, McPartlin J, McNulty H, Ward M, Strain JJ, Weir DG, Scott JM. Importance of both folic acid and vitamin B12 in reduction of risk of vascular disease. Lancet 2002; 359:227?228.
  ²⁰⁰ Coronary blood flow in patients with stable coronary artery disease treated long term with folic acid and vitamin B12. Bleie Ø, Strand E, Ueland PM, Vollset SE, Refsum H, Igland J, Nordrehaug JE, Nygård OK. Department of Heart Disease, Haukeland University Hospital, Bergen, Norway. oyvind.bleie@helse-bergen.no; Coron Artery Dis. 2011 Jun;22(4):270-8.
  ²⁰¹ Gastric status and vitamin B12 levels in cardiovascular patients. van Oijen MG, Sipponen P, Laheij RJ, Verheugt FW, Jansen JB. Department of Medicine, Division of Gastroenterology, Radboud University Nijmegen Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, the Netherlands. M.vanOijen@mdl.umcn.nl; Dig Dis Sci. 2007 Sep;52(9):2186-9. Epub 2007 Apr 11.
  ²⁰² Homocysteine, vitamin B12 and folate levels in premature coronary artery disease. Sadeghian S, Fallahi F, Salarifar M, Davoodi G, Mahmoodian M, Fallah N, Darvish S, Karimi A; Tehran Heart Center. Research Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. sadeghian15@yahoo.com; BMC Cardiovasc Disord. 2006 Sep 26;6:38.
  ²⁰³ Can reduced folic acid and vitamin B12 levels cause deficient DNA methylation producing mutations which initiate atherosclerosis? Newman PE. Med Hypotheses. 1999 Nov;53(5):421-4.
  ²⁰⁴ Van Guelpen B, Hultdin J, Johansson I, et al. Folate, vitamin B12, and risk of ischemic and hemorrhagic stroke: a prospective, nested case-referent study of plasma concentrations and dietary intake. Stroke 2005;36:1426-31.
• Deep-vein thrombosis (blood clot in arm or leg).
  ²⁰⁵ Increased p-homocysteine--a risk factor for thrombosis. Jensen OK, Ingerslev J. Center for haemofili og trombose, klinisk immunologisk afdeling, Arhus Universitetshospital, Skejby Sygehus; Ugeskr Laeger. 1998 Jul 20;160(30):4405-10.
  ²⁰⁶ Vitamin B12 deficiency causing hyperhomocysteinaemia and cerebral venous sinus thrombosis. Whyte AF, Jones DL, Dreyer MD; Intern Med J. 2012 May;42(5):601-3.
  ²⁰⁷ Vitamin B12 deficiency, hyperhomocysteinemia and thrombosis: a case and control study. Remacha AF, Souto JC, Piñana JL, Sardà MP, Queraltó JM, Martí-Fabregas J, García-Moll X, Férnandez C, Rodriguez A, Cuesta J. Department of Hematology, Complejo Hospitalario Toledo, Hospital Virgen de la Salud, Avenida Barber 30, 45004, Toledo, Spain. aremacha@sescam.jccm.es; Int J Hematol. 2011 Apr;93(4):458-64. Epub 2011 Apr 8.
  ²⁰⁸ Homocysteine, vitamin B12 and folic acid levels in psoriatic patients and correlation with disease severity. Brazzelli V, Grasso V, Fornara L, Moggio E, Gamba G, Villani S, Borroni G. Department of Human and Hereditary Pathology, Institute of Dermatology, University of Pavia and Foundation IRCCS Policlinico San Matteo, Pavia, Italy. vbrazzelli@libero.it; Int J Immunopathol Pharmacol. 2010 Jul-Sep;23(3):911-6.
  ²⁰⁹ Blz. 44, 45, 76, 119, 121, 127, 167, 212, 257 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Elevated homocysteine levels, as a result of a vitamin B12 deficiency. Homocysteine is a potentially dangerous amino acid. When homocysteine accumulates in the bloodstream, the risk of coronary heart disease, stroke and blood clots increases significantly. A high homocysteine level can damage blood vessels and help cause atherosclerosis with a increased risk of heart attacks and strokes (developed in a relatively short time). Homocysteine can also transform cholesterol into its harmful form, increasing the chance of blood vessels being damaged. It can also contribute to the disruption of the functioning of the endothelial cells (inside of the blood vessels). When pregnant, an elevated homocysteine level in the blood can also increase susceptibility to preeclampsia, a potentially dangerous complication of the pregnancy characterised by high blood pressure.
  ²¹⁰ Blz. 37, 46, 47, 119, 122, 123, 126-131, 135-137, 169 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²¹¹ Koyama K, Usami T, Takeuchi O, Morozumi K, Kimura G. Efficacy of methylcobalamin on lowering total homocysteine plasma concentrations in haemodialysis patients receiving high-dose folic acid supplementation. Nephrol Dial Transplant 2002 ; 17(5):916-922
  ²¹² Manzanares W, Hardy G. Vitamin B12: the forgotten micronutrient for critical care. Curr Opin Clin Nutr Metab Care 2010; 13(6):662-8.
  ²¹³ Homocysteine, folate and vitamin b12 in patients with coronary heart disease. Genser D, Prachar H, Hauer R, Halbmayer WM, Mlczoch J, Elmadfa I. Department of Nutrition, University of Vienna, Vienna, Austria. Dieter.Genser@univie.ac.at; Ann Nutr Metab. 2006;50(5):413-9. Epub 2006 Jul 17.
  ²¹⁴ Hyperhomocysteinaemia and vitamin B12 deficiency: the long-term effects in cardiovascular disease. van Oijen MG, Vlemmix F, Laheij RJ, Paloheimo L, Jansen JB, Verheugt FW. Department of Gastroenterology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. M.vanOijen@mdl.umcn.nl; Cardiology.  2007;107(1):57-62. Epub 2006 Jun 6.
  ²¹⁵ Homocysteine and coronary heart disease. Clarke R, Lewington S. Clinical Trial Service Unit and Epidemiological Studies Unit, Radcliffe Infirmary, University of Oxford, Oxford, United Kingdom. robert.clarke@ctsu.ox.ac.uk; Semin Vasc Med. 2002 Nov;2(4):391-9; Semin Vasc Med. 2002 Nov;2(4):391-9.
  ²¹⁶ Homocysteine, folic acid and B-group vitamins in obstetrics and gynaecology. de la Calle M, Usandizaga R, Sancha M, Magdaleno F, Herranz A, Cabrillo E.Department of Obstetrics and Gynaecology, Hospital La Paz, Paseo de la Castellana n 261, 28046 Madrid, Spain; Eur J Obstet Gynecol Reprod Biol. 2003 Apr 25;107(2):125-34.
  ²¹⁷ Update on Cobalamin, Folate, and Homocysteine; Ralph Carmel, Ralph Green, David S. Rosenblatt, and David Watkins American Society of Hematology; Hematology Am Soc Hematol Educ Program. 2003:62-81.
  ²¹⁸ Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study.Hooshmand B, Solomon A, Kåreholt I, Leiviskä J, Rusanen M, Ahtiluoto S, Winblad B, Laatikainen T, Soininen H, Kivipelto M., Stockholm, Sweden. babak.hooshmand@ki.se; Neurology. 2010 Oct 19;75(16):1408-14.
  ²¹⁹ Increased concentrations of homocysteine in the cerebrospinal fluid in patients with fibromyalgia and chronic fatigue syndrome Regland B, Andersson M, Abrahamsson L, Bagby J, Dyrehag LE, Gottfries CG. Scand J Rheumatol. 1997;26(4):301-7.
  
• Dizziness vertigo, balance problems (combined with cardiovascular disease).
  ²²⁰ Acute presentation of dizziness in vitamin B12 deficient old patient of cardiac disease: a case report. Singh B, Arora S.GB Pant Hospital, Room 418, Dept of Biochemistry, Academic Block, Jawahar Lal Nehru Marg, New Delhi, India. bhawna172@gmail.com; Clin Chim Acta. 2010 Dec 14;411(23-24):2104-6. Epub 2010 Aug 22.  
  ²²¹ Orthostatic tolerance in older patients with vitamin B12 deficiency before and after vitamin B12 replacement.Moore A, Ryan J, Watts M, Pillay I, Clinch D, Lyons D.Dept. of Medical Gerontology, Clinical Age Assessment Unit, Mid-Western Regional Hospital, Limerick, Republic of Ireland. alanmoore@elivefree.net; Clin Auton Res. 2004 Apr;14(2):67-71.
  ²²² Blz. 32-44, 55, 73, 79, 80, 85, 96, 102, 103, 186, 194, 208, 219, 222, 250, 251, 255, 257, 269 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Orthostatic hypotension (blood pressure is too low while standing, causing fainting).
  ²²³ Orthostatic hypotension revealing vitamin B12 deficiency. Girard P, Lebrun C, Peyrade F, Brunetto JL, Chatel M. Service de Neurologie, Hôpital Pasteur, Nice; Rev Neurol (Paris). 1998 May;154(4):342-4.
  ³³⁰ Ultrastructure of the H. pylori microbe in individuals having macrocytosis and B12 deficiency. Khubchandani SR, Kulkarni S, Teckchandani S, Chitale A.Jaslok Hospital & Research Center, Deshmukh Marg, Mumbai, India. shailakhubchandani@yahoo.co.in; Ultrastruct Pathol. 2011 Oct;35(5):204-8. Epub 2011 Aug 25.
• Shortness of breath and chest pain; angina.
  ²²⁴ New observation of pernicious anemia with syndrome of intermittent claudication and effort angina disappearing after treatment of the anemia, CAHEN P, BRUN F, BLANC J.; Lyon Med. 1954 Jun 6;86(23):484-8.
  ²²⁵ Chest Pain, Frequent Cramping, Weakness. By Lisa Sanders, M.D. New York Times. Published: February 29, 2004
  ³³⁵ Blz. 125 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Coronary heart disease
  ²²⁶ Blz. 44-46, 76, 119, 121, 124, 129, 130, 133, 167, 212 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²²⁷ Herzlich BC et al. Relationship among homocyst(e)ine, vitamin B-12 and cardiac disease in the elderly: association between vitamine B12 deficiency and decreased left ventricular ejection fraction. Journal of Nutrition 1996;126:1249S-1253.
  ²²⁸ Bleie O, Strand E, [..], Nygård OK. Coronary blood flow in patients with stable coronary artery disease treated long term with folic acid and vitamin B12. Coron Artery Dis 2011; 22(4):270-8
• Increased risk of cardiovascular disorders, arteriosclerosis and arterial and venous thromboembolism, cerebrovascular accidents.
  ²²⁹ Blz. 125,127, 128, 130 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²³⁰ Liu LJ, Yin XY, Ikeda K, Sullivan DH, Eisen HJ. Micronutrients, inflammation and congestive heart failure among the elderly: nutritional perspectives on primary prevention and clinical. Clinical and Experimental Pharmacology and Physiology, 2007; 34:S14-S16.
  ²³¹ Cardiovascular lesions in cobalt-vitamin B12 deficient sheep. Mohammed R, Lamand M.; Ann Rech Vet. 1986;17(4):447-50.
• (minor) TIA/CVA (stroke), “silent brain infarcts”.
  ²³² Blz. 23, 25, 59, 71, 119, 125, 128, 156, 189, 220 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²³³ Weikert C, Dierkes J, Hoffmann K, Berger K, Drogan D, Klipstein-Grobusch K, Spranger J, Möhlig M, Luley C, Boeing H. B Vitamin Plasma Levels and the Risk of Ischemic Stroke and Transient Ischemic Attack in a German Cohort. Stroke 2007; 38(11):2912-8.
  ²³⁴ Salemi G, Gueli MC, [..], Lupo I. Blood levels of homocysteine, cysteine, glutathione, folic acid, and vitamin B(12) in the acute phase of atherothrombotic stroke. Neurol Sci 2009 May 30.
  ²³⁵ Arauz A, Hoyos L, Cantú C, Jara A, Martínez L, García I, Fernández MD, Alonso E. Mild Hyperhomocysteinemia and Low Folate Concentrations as Risk Factors for Cervical Arterial Dissection. Cerebrovasc Dis 2007; 24(2-3):210-214.
  ²³⁶ Yilmaz N, Yilmaz M, Pence S, Ozaslan J, Kocoglu H, Yilmaz G. Determination of serum B12 vitamin and folic acid levels in patient with stroke. Acta Medica (Hradec Kralove) 2001; 44(1):37-9.
  ²³⁷ Mac Donalds Holmes, J. ~ Cerebral manifestations of vitamin B12 deficiency. British Medical Journal. 1956; dec: 1394 - 1398.
  ²³⁸ Vitamin B12 deficiency: an unusual cause for recurrent generalised seizures with pancytopaenia.Naha K, Dasari S, Vivek G, Prabhu M. BMJ Case Rep. 2012 Sep 3;2012. pii: bcr2012006632. doi: 10.1136/bcr-2012-006632.
• Heart attack
  ²³⁹ Blz. 25, 45, 119, 123-125, 127, 128, 130, 133, 137, 138, 189, 217, 227 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁴⁰ Liu LJ, Yin XY, Ikeda K, Sullivan DH, Eisen HJ. Micronutrients, inflammation and congestive heart failure among the elderly: nutritional perspectives on primary prevention and clinical. Clinical and Experimental Pharmacology and Physiology, 2007; 34:S14-S16.
  ²⁴¹ Verhoef P. et al. Homocysteine metabolism and risk of myocardial infarction. Relation with vitamins B6, B12 and folate. American Journal of Epidemiology 1996;143:845-859.
  ²⁴² Association of vitamin B12 deficiency with fatigue and depression after lacunar stroke. Huijts M, Duits A, Staals J, van Oostenbrugge RJ. PLoS One. 2012;7(1):e30519. Epub 2012 Jan 20.
  ²⁴³ Anemia and mortality in heart failure patients a systematic review and meta-analysis. Groenveld HF, Januzzi JL, Damman K, van Wijngaarden J, Hillege HL, van Veldhuisen DJ, et al. J Am Coll Cardiol. 2008 Sep 2;52(10):818-27.
• Heart palpitations
  ²⁴⁴ Autoimmune pernicious anaemia as a cause of collapse, heart failure and marked panyctopaenia in a young patient. Carey J, Hack E. Department of Infectious Diseases, Fremantle Hospital and Health Service, Fremantle, Western Australia, Australia. drjustincarey@gmail.com; BMJ Case Rep. 2012 May 8;2012.
  ²⁴⁵ Blz. 44 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Cardiac arrhythmia,fast pulse or weak, low pulse.
  ²⁴⁶ Autonomic dysfunction and hemodynamics in vitamin B12 deficiency. Beitzke M, Pfister P, Fortin J, Skrabal F. Department of Internal Medicine, Krankenhaus der Barmherzigen Brüder, Teaching Hospital Karl-Franzens-University Graz, Austria; Auton Neurosci. 2002 Apr 18;97(1):45-54.
  ²⁴⁷ Autoimmune pernicious anaemia as a cause of collapse, heart failure and marked panyctopaenia in a young patient. Carey J, Hack E.; Australia. drjustincarey@gmail.com; BMJ Case Rep. 2012 May 8;2012.
• Lung disease; lung embolism (blood clots in the lungs).
  ²⁴⁸ Blz.45, 76, 121, 127, 167, 212, 257 “Is het Misschien B12-tekort?” Sally M. Pacholok enJeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁴⁹ Fimognari FL, Loffredo L, [..], D'Angelo A. Hyperhomocysteinaemia and poorvitamin B status in chronic obstructive pulmonary disease. Nutr Metab Cardiovasc Dis2009; 19(9):654-9.
  ²⁵⁰ Research advances in the treatment of hyperhomocysteinemia;Cheng S, Feng J,Wang X.; China; Sheng Li Ke Xue Jin Zhan. 2011 Oct;42(5):329-34.
  ²⁵¹ Folate/vitamin-B12 prevents chronic hyperhomocysteinemia-induced tauHyperphosphorylation and memory deficits in aged rats;Wei W, Liu YH, Zhang CE,Wang Q, Wei Z, Mousseau DD, Wang JZ, Tian Q, Liu GP. China.; J Alzheimers Dis.2011;27(3):639-50.

Psychological and/or psychiatric problems

• Confusion
  ²⁵² Blz. 29, 44, 50, 56, 61, 69, 71, 79, 112, 115, 184, 186, 191, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁵³ Domisse, J. ~ Subtle vitamin B12 deficiency and psychiatry: a largely unnoticed but devastating relation ship. Medical Hypotheses. 1991; 34 (2): 131 - 140.
  ²⁵⁴ Psychiatric manifestations of vitamin B12 deficiency: a case report. Durand C, Mary S, Brazo P, Dollfus S. France. Encephale. 2003 Nov-Dec;29(6):560-5 Vitamin B12 deficiency associated with symptoms of frontotemporal dementia. Blundo C, Marin D, Ricci M.;Italy. cablu@tin.it;
  ²⁵⁵ Neurol Sci. 2011 Feb;32(1):101-5.
• Anxiety
  ²⁵⁶ Blz. 54, 95, 109, 165, 172, 195, 196, 223 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁵⁷ Goggans, F.C. ~ A case of mania secondary to vitamin B12 deficiency. American Journal of Medicine. 1984; 141 (2):300 - 301.
  ²⁵⁸ Parasitophobia as the presenting symptom of vitamin B12 deficiency. Pope FM; Practitioner. 1970 Mar;204(221):421-2.
  ³³¹ Intake of B vitamins in childhood and adult life in relation to psychological distress among women in a British birth cohort. Mishra GD, McNaughton SA, O'Connell MA, Prynne CJ, Kuh D.;UK. g.mishra@nshd.mrc.ac.uk; Public Health Nutr. 2009 Feb;12(2):166-74
• Psychiatric disorders: mood swings; depersonalisation; personality shifts (“you don’t feel like yourself anymore”), suspicion, paranoia, behavioural shifts.
  ²⁵⁹ Blz. 34, 43, 46, 61, 115 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁶⁰ Neuropsychiatric disorders caused by cobalamin deficiency in the absence of anemia or macrocytosis J Lindenbaum, EB Healton, DG Savage, JC Brust, TJ Garrett, ER Podell, PD Marcell, SP Stabler, and RH Allen NEJM Volume 318:1720-1728.  
  ²⁶¹ Schulman, R. ~ A survey of vitamin B12 deficiency in an elderly psychiatric population. British Journal of Psychiatry. 1967a; 113: 241 - 251.
  ²⁶² Domisse, J. ~ Subtle vitamin B12 deficiency and psychiatry: a largely unnoticed but devastating relation ship. Medical Hypotheses. 1991; 34 (2): 131 - 140.
  ²⁶³ Negative symptoms presenting as neuropsychiatric manifestation of vitamin B12 deficiency. Sahoo MK, Avasthi A, Singh P. Indian J Psychiatry. 2011 Oct;53(4):370-1.
  ²⁶⁴ Vitamin B12 deficiency presenting with an acute reversible extrapyramidal syndrome. Kumar S. Neurology Unit, Department of Neurological Sciences, Christian Medical College Hospital, Vellore - 632 004, India. drsudhirkumar@yahoo.com; Neurol India. 2004 Dec;52(4):507-9.
  ²⁶⁵ Mood disorder with mixed, psychotic features due to vitamin b12 deficiency in an adolescent: case report. Tufan AE, Bilici R, Usta G, ErdoÄŸan A. Assistant Professor, Abant Izzet Baysal University Medical Faculty, Department of Child and Adolescent Psychiatry, Baysal, Turkey. tevrenus@yahoo.com.; Child Adolesc Psychiatry Ment Health. 2012 Jun 22;6(1):25.
  ²⁶⁶ Psychiatric syndromes in pernicious anaemia. Ko SM, Liu TC. Department of Psychological Medicine, National University of Singapore; Singapore Med J. 1992 Feb;33(1):92-4.
  ²⁶⁷ Mood disorder with mixed, psychotic features due to vitamin b12 deficiency in an adolescent: case report. Tufan AE, Bilici R, Usta G, ErdoÄŸan A.; Turkey. tevrenus@yahoo.com; Child Adolesc Psychiatry Ment Health. 2012 Jun 22;6(1):25.
• Compulsive behaviour, aggression, violent behaviour
  ²⁶⁸ Blz. 43, 60, 90, 115, 209 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁶⁹ Obsessive compulsive disorder as early manifestation of B12 deficiency. Valizadeh M, Valizadeh N. Indian J Psychol Med. 2011 Jul;33(2):203-4.
  ²⁷⁰ Cobalamin deficiency presenting as obsessive compulsive disorder: case report. Sharma V, Biswas D. Department of Psychiatry, Kailash Hospital, Greater Noida, Uttar Pradesh, India. doc.v.sharma@hotmail.com; Gen Hosp Psychiatry. 2012 Sep;34(5):578.e7-8.
  ²⁷¹ Vitamin B12 and folic acid serum levels in obsessive compulsive disorder. Hermesh H, Weizman A, Shahar A, Munitz H.; Geha Psychiatric Hospital, Beilinson Medical Center, Sackler School of Medicine, Tel Aviv University, Israel; Acta Psychiatr Scand. 1988 Jul;78(1):8-10
  ²⁷² B12 deficiency and psychiatric disorders: case report and literature review.Zucker DK, Livingston RL, Nakra R, Clayton PJ.; Biol Psychiatry. 1981 Feb;16(2):197-205.
• Perception disorder, paranoid delusions (for instance completely miscomprehending what someone is trying to tell you).
  ²⁷³ Blz. 26, 53, 56, 60, 69, 106, 108, 112, 115, 187, 209 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁷⁴ Lindenbaum,; e.a. ~ Neuropsychiatric disorders caused by cobalamine deficiency in the absence of anemia or macrocytosis. New England Journal of Medicine. 1988; 318: 1720 - 8.
  ²⁷⁵ Schulman, R. ~ The present status of vitamin B12 and folic acid deficiency in psychiatric illness. Canadian Psychiatric Association. 1972; 17: 205 - 216.
  ²⁷⁶ Schulman, R. ~ Vitamin B12 deficiency and psychiatric illness. British Journal of Psychiatry. 1967b; 113: 252 - 256.
  ²⁷⁷ Zucker, D.K.; e.a. ~ B12 deficiency and psychiatric disorders: case report and literature review. Biological Psychiatry. 1981; 16: 197 - 205.
• Hallucinations
  ²⁷⁸ Blz. 43, 107, 108, 112, 115, 209, 269 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁷⁹ Shanoudy, H.; Salem, A.G. ~ Neuropsychiatric manifestations of vitamin B12-deficiency in the absence of anemia or macrocytosis: a case report. South Dakota Journal of Medicine. 1992; 45 (5): 129 - 131.
  ²⁸⁰ Psychotic disorder, hypertension and seizures associated with vitamin B12 deficiency: a case report. Dogan M, Ariyuca S, Peker E, Akbayram S, Dogan ŞZ, Ozdemir O, Cesur Y.; Turkey. doganmurat.md@gmail.com; Hum Exp Toxicol. 2012 Apr;31(4):410-3.
  ²⁸¹ Correlations between cognitive, behavioural and psychological findings and levels of vitamin B12 and folate in patients with dementia. Engelborghs S, Vloeberghs E, Maertens K, Mariën P, Somers N, Symons A, Clement F, Ketels V, Saerens J, Goeman J, Pickut BA, Vandevivere J, De Deyn PP. Department of Neurology & Memory Clinic, Middelheim General Hospital, Antwerp, Belgium; Int J Geriatr Psychiatry. 2004 Apr;19(4):365-70.
• Bipolar disorder (manic depression).
  ²⁸² Blz. 63, 97, 105-107, 116, 118, 165, 209 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁸³ Wieck, H.H.; Heerklotz, B. ~ Vitamin B12-mangelzustände aus neuropsychiatrischer sicht. Medizinisches Monatschrift. 1972; 26: 7 - 10.
  ²⁸⁴ Unilateral tremor induced by risperidone in a patient with acute mania: vitamin B12 deficiency as possible mediating factor. Kattimani S, Padhy SK, Annamalai I. Indian J Pharmacol. 2012 May;44(3):421-2.
• Schizophrenia
  ²⁸⁵ Plasma homocysteine, folate and B12 in chronic schizophrenia.Haidemenos A, Kontis D, Gazi A, Kallai E, Allin M, Lucia B.; Greece. dralex@otenet.gr ; Prog Neuropsychopharmacol Biol Psychiatry. 2007 Aug 15;31(6):1289-96.
  ²⁸⁶ Malignant catatonia in a patient with bipolar disorder, B12 deficiency, and neuroleptic malignant syndrome: one cause or three?Lewis AL, Pelic C, Kahn DA. USA; J Psychiatr Pract. 2009 Sep;15(5):415-22.
  ²⁸⁷ Hyperhomocysteinemia and schizophrenia: case control study; Mabrouk H, Douki W, Mechri A, Younes MK, Omezzine A, Bouslama A, Gaha L, Najjar MF.; Tunisie. hajer mabrouk@yahoo.fr ; Encephale. 2011 Sep;37(4):308-13.
  ²⁸⁸ Reduced folic acid, vitamin B12 and docosahexaenoic acid and increased homocysteine and cortisol in never-medicated schizophrenia patients: implications for altered one-carbon metabolism. Kale A, Naphade N, Sapkale S, Kamaraju M, Pillai A, Joshi S, Mahadik S. Department of Nutritional Medicine, Interactive Research School for Health Affairs, Bharati Vidyapeeth University, Pune 411043, India; Psychiatry Res. 2010 Jan 30;175(1-2):47-53. Epub 2009 Dec 6.
  ³³⁶ Blz. 21, 105, 106, 115, 165, 209 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷⁵⁸ Randomized Multicenter Investigation of Folate Plus Vitamin B12 Supplementation in Schizophrenia Joshua L. Roffman, MD, MMSc; J. Steven Lamberti, MD; Eric Achtyes, MD, MS; Eric A. Macklin, PhD; Gail C. Galendez, BS; Lisa H. Raeke, MA; Noah J. Silverstein, BA; Jordan W. Smoller, MD, ScD; Michele Hill, MD; Donald C. Goff, MD JAMA Psychiatry. 2013;70(5):481-489. doi:10.1001/jamapsychiatry.2013.900.
  http://archpsyc.jamanetwork.com/article.aspx?articleid=1660588
  gezondheid.plusonline.nl/vitaal-blijven-met-vitamines-en-mineralen/nieuws/10526/foliumzuur-helpt-bij-schizofrenie
• Developmental disorders such as ADHD, PDD-NOS and autism
  ²⁸⁹ Blz. 165 ADHD, Blz. 160, 275 PDD-NOS “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁹⁰ Nutrition and performance in children. Fanjiang G, Kleinman RE. USA. Curr Opin Clin Nutr Metab Care. 2007 May;10(3):342-7.
  ²⁹¹ Effects of nutrients (in food) on the structure and function of the nervous system: update on dietary requirements for brain. Part 1: micronutrients. Bourre JM.France; jean-marie.bourre@fwidal.inserm.fr; J Nutr Health Aging. 2006 Sep-Oct;10(5):377-85.
• Autism; problems in initiating and allowing contact; behavioural, cognitive, and motor skill problems; unexpected mood shifts.
  ²⁹² Vitamin B12 optic neuropathy in autism. Pineles SL, Avery RA, Liu GT.Neuro-ophthalmology Service, Division of Neuro-Ophthalmology, Hospital of the University of Pennsylvania, Department of Neurology, University of Pennsylvania School of Medicine, 3400 Spruce St, Philadelphia, PA 19104, USA; Pediatrics. 2010 Oct;126(4):e967-70. Epub 2010 Sep 20. (NB: www.drneubrander.com hoe met vitamine B12 Methylcobalamine-injecties (jonge) autistische kinderen in de VS zeer succesvol geholpen worden.)
  ²⁹³ Blz. 21, 26, 43, 142, 145, 155, 158-162, 164, 165, 200, 212, 219, 233, 256, 259, 265, 266, 272-276, 280, 283-285, 290, Autisme “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ²⁹⁴ Hyperhomocysteinemia among Omani autistic children: a case-control study. Ali A, Waly MI, Al-Farsi YM, Essa MM, Al-Sharbati MM, Deth RC; Oman. amanat@squ.edu.om; Acta Biochim Pol. 2011;58(4):547-51.
  ²⁹⁵ Vitamin supplementation reduces the level of homocysteine in the urine of autistic children. Kałużna-Czaplińska J, Michalska M, Rynkowski J.;Poland; jkaluzna@p.lodz.pl; Nutr Res. 2011 Apr;31(4):318-21.
• Depression, feeling down; no will to live, no more passion for anything; giving up; indifference; apathy (lack of interest); being “fed up” ; lack of empathy. Low B12 values are strongly associated with experiencing depression.
  ²⁹⁶ In 2002 publiceerden de Nederlandse onderzoekers Tiemeier, van Tuijl, Hofman, Meijer, Kiliaan, en Breteler een artikel over het verband tussen depressie en het hebben van (te) lage vitamine B12 waarden in het bloed in the American Journal of Psychiatry. Het onderzoek vond plaats onder bijna 4000 ouderen. Eén van hun conclusies: Lage B12 waarden zijn sterk gerelateerd aan het hebben van een depressie. Titel van hun werk: “Vitamin B12, folate, and homocysteine in depression: The Rotterdam study”. 159(12):2099-101.
  ²⁹⁷ Status of Vitamins B-12 and B-6 but Not of Folate, Homocysteine, and the Methylenetetrahydrofolate Reductase C677T Polymorphism Are Associated with Impaired Cognition and Depression in Adults; Moorthy D, Peter I, [..], Troen AM.  J Nutr 2012; 142(8):1554-60  Skarupski KA, Tangney C, [..],
  ²⁹⁸ Morris MC. Longitudinal association of vitamin B-6, folate, and vitamin B-12 with depressive symptoms among older adults over time. Am J Clin Nutr 2010; 92(2):330-5.
  ²⁹⁹ Treatment of depression: time to consider folic acid and vitamin B12, Alec Coppen, Christina Bolander-Gouaille Journal of Psychopharmacology 19(1) (2005) 59-65J Psychopharmacol. 2005 Jan;19(1):59-65.
  ³³² Sánchez-Villegas A, Doreste J, [..], Martínez-González MA. Association between folate, vitamin B(6) and vitamin B(12) intake and depression in the SUN cohort study. J Hum Nutr Diet 2009; 22(2):122-33.
• Lack of concentration no longer being able to think clearly, “brain fog”, drowsiness, light-headedness.
  ³⁰⁰ Blz. 21, 77, 105, 160 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁰¹ Conversion from Mild Cognitive Impairment to Dementia: Influence of Folic Acid and Vitamin B12 Use in the VITA Cohort.; Blasko I, Hinterberger M, Kemmler G, Jungwirth S, Krampla W, Leitha T, Heinz Tragl K, Fischer P.;I. Blasko, Austria, imrich.blasko@i-med.ac.at.; J Nutr Health Aging. 2012;16(8):687-94.
  ³⁰² Psychiatric manifestations of vitamin B12 deficiency: a case report. Durand C, Mary S, Brazo P, Dollfus S. France. Encephale. 2003 Nov-Dec;29(6):560-5 Vitamin B12 deficiency associated with symptoms of frontotemporal dementia. Blundo C, Marin D, Ricci M.;Italy. cablu@tin.it;
  ³⁰³ Neurol Sci. 2011 Feb;32(1):101-5.
• Intelligence, unused IQ potential.
  ³⁰⁴ Blz. 63, 259, 262, 264-266, 277, 278 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁰⁵ Louwman MWJ et al. Signs of impaired cognitive function in adolescents with marginal cobalamin status. Am J Clin Nutr 2000;72:762-769.
  ³⁰⁶ Tangney CC, Tang Y, [..], Morris MC. Biochemical indicators of vitamin B12 and folate insufficiency and cognitive decline. Neurology 2009; 72(4):361-7.
  ³⁰⁷ Stolhoff, K.; Schulte, F.J. ~ Vitamin B12 and brain development. Europian Journal of Pediatrics. 1987; 146: 201 - 205.
  ³⁰⁸ Vitamin B12 status and rate of brain volume loss in community-dwelling elderly. Vogiatzoglou A, Refsum H, Johnston C, Smith SM, Bradley KM, de Jager C, Budge MM, Smith AD. Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Rd., Oxford OX1 3QX, UK. anna.vogiatzoglou@dpag.ox.ac.uk; Neurology. 2008 Sep 9;71(11):826-32.
  ³⁰⁹ Low vitamin B-12 status and risk of cognitive decline in older adults. Clarke R, Birks J, Nexo E, Ueland PM, Schneede J, Scott J, Molloy A, Evans JG. University of Oxford, . robert.clarke@ctsu.ox.ac.uk; Am J Clin Nutr. 2007 Nov;86(5):1384-91.
  ³¹⁰ A trial of B vitamins and cognitive function among women at high risk of cardiovascular disease. Kang JH, Cook N, Manson J, Buring JE, Albert CM, Grodstein F.Channing Laboratory, Boston, MA 02115, USA. nhjhk@channing.harvard.edu; Am J Clin Nutr. 2008 Dec;88(6):1602-10.
  ³¹¹ Oral folic acid and vitamin B-12 supplementation to prevent cognitive decline. Feng L.Folic acid and vitamin B-12 supplementation to prevent cognitive decline in community-dwelling older adults with depressive symptoms--the Beyond Ageing Project: a randomized controlled trial. [Am J Clin Nutr. 2012; Am J Clin Nutr. 2012 May;95(5):1289-90
• Forgetfulness, short-term memory problems.
  ³¹² Blz. 33, 34, 43, 44, 46, 47, 50, 51, 56, 60, 61, 69, 82, 83, 85, 88, 101, 105, 112, 115, 152, 164, 178, 184, 186, 192, 208, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³¹³ Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Tangney CC, Aggarwal NT, [..], Morris MC.; Neurology 2011; 77(13):1276-82
  ³²⁵ Nutrient biomarker patterns, cognitive function, and MRI measures of brain aging. Bowman GL, Silbert LC, [..], Quinn JF. Neurology 2012; 78(4):241-9.
• Difficulty finding words when speaking
  ³¹⁴ Blz. 143, 158, 159, 162, 164, 261, 262, 263, 271, 278, 281-283 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³¹⁵ Tangney CC, Aggarwal NT, [..], Morris MC. Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology 2011; 77(13):1276-82
• No sense of well-being, the joy of living, the “joie de vivre”, the humour, putting things into perspective, the will, the flair: bit by bit, it feels as if it has all been squeezed out and is creeping away. There is an increasing feeling of crankiness, moodiness, irritability (“having a short fuse”), of possible sudden aggression and/or mood changes. There can be an increase in unreasonable behaviour, even up to severe psychological complaints, panic attacks and even suicidal behaviour.
  ³¹⁶ Blz. 23, 34, 43, 44, 47, 50, 51, 54, 61, 62, 80, 83, 85, 88, 105, 106, 107-112, 114, 115, 118, 132, 165, 178, 186, 209, 215, 255, 269 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³¹⁷ Sánchez-Villegas A, Doreste J, [..], Martínez-González MA. Association between folate, vitamin B(6) and vitamin B(12) intake and depression in the SUN cohort study. J Hum Nutr Diet 2009; 22(2):122-33.
  ³¹⁸ Eilenburg, M.D. ~ Psychiatric illness and pernicious anaemia: a clinical re-evaluation. Journal of Mental Science. 1960; 106: 1539 - 1548.
  ³¹⁹ A study of neurobehavioral, clinical psychometric, and P3 changes in vitamin B12 deficiency neurological syndrome. Kalita J, Agarwal R, Chandra S, Misra UK. Nutr Neurosci. 2012 Jul 9.
  ³²⁰ Subtle vitamin-B12 deficiency and psychiatry: a largely unnoticed but devastating relationship?Dommisse J.; Med Hypotheses. 1991 Feb;34(2):131-40.
• Trouble sleeping
  ³²¹ Blz. 115 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³²² Chronobiological sleep disorders and their treatment possibilities.Brunner DP, Wirz-Justice A.Abteilung für Chronobiologie, Psychiatrische Universitätsklinik, Basel; Ther Umsch. 1993 Oct;50(10):704-8.
  ³²³ Vitamin B12 treatment for sleep-wake rhythm disorders. Okawa M, Mishima K, Nanami T, Shimizu T, Iijima S, Hishikawa Y, Takahashi K.; Japan. Sleep. 1990 Feb;13(1):15-23.
  ³²⁴ Dementia: classification and aspects of treatment. Gottfries CG. Sweden; Psychopharmacol Ser. 1988;5:187-95.
• Psychosis
  ³³⁷ Blz. 40, 44, 46, 55, 58, 80, 88, 90, 101, 105, 110, 111, 113, 116, 209, 222, 235, 269, 290 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³³⁸ Vitamin B12 and folate serum levels in newly admitted psychiatric patients Vladimir Lerner, Michael Kanevsky, Tzvi Dwolatzky, Tsvi Rouach, Ram Kamin, Chanoch Miodownik Clinical Nutrition (2006) 25, 60-67.
  ³³⁹ Evans, Dwight L.; e.a. ~ Organic psychosis without anemia or spinal cord symptoms in patients with vitamin B12 deficiency. American Journal of Medicine. 1983; 140 (2): 218 - 221.
  ³⁴⁰ Medizinische Klinik ~ Funiculäre spinalerkrankungen und B12 avitaminotische Psychose. Medizinische Klinik (München). 1967; 62: 767 - 770.
  ³⁴¹ Wieck, H.H.; e.a. ~ Funktionspsychosen als manifestationen der B12-avitaminosen. Deutsche Medizinische Wochenschrift (Stuttgart). 1969; 94: 1473 - 1476.
  ³⁴² Mood disorder with mixed, psychotic features due to vitamin b12 deficiency in an adolescent: case report. Tufan AE, Bilici R, Usta G, ErdoÄŸan A. Assistant Professor, Abant Izzet Baysal University Medical Faculty, Department of Child and Adolescent Psychiatry, Baysal, Turkey. tevrenus@yahoo.com.; Child Adolesc Psychiatry Ment Health. 2012 Jun 22;6(1):25.
  ³⁴³ Acute psychotic depression as a sole manifestation of vitamin B12 deficiency.;Bar-Shai M, Gott D, Marmor S.; Israel. barshaimarina@gmail.com; Psychosomatics. 2011 Jul-Aug;52(4):384-6.
  ³⁴⁴ NB: Een psychose kan ook geprovoceerd worden door gebruik van lachgas (Distikstof(mon)oxide; N₂O) met als gevolg een acuut groot Vitamine B12-tekort: Nitrous oxide "whippit" abuse presenting with cobalamin responsive psychosis. Sethi NK, Mullin P, Torgovnick J, Capasso G.;Department of Neurology, Saint Vincent's Hospital and Medical Centers, New York, NY 10011, USA. sethinitinmd@hotmail.com; J Med Toxicol. 2006 Jun;2(2):71-4.
  ³⁴⁵ Myeloneuropathy from whipped cream bulbs presenting as conversion disorder.Brett A; Postgraduate Centre, Graylands Hospital, Mt Claremont, Western Australia, Australia.The Australian and New Zealand Journal of Psychiatry [1997, 31(1):131-132]
• Postnatal depression or psychosis, partly due to the enormous force and energy a birth requires, the physical and mental balance of a woman, which was precarious to begin with due to vitamin B12 deficiency, can suddenly shift dramatically.
  ³⁴⁶ Blz. 109, 110, 111, 209, 290, “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁴⁷ http://vita-info.nl/2012/07/b12-psychose/
  ³⁴⁸ The Utility of Laboratory Screening in Medically Ill Patients with Psychiatric Symptoms; Catalano G.1; Catalano M.C.2; O'Dell K.J.2; Humphrey D.A.3; Fritz E.B.4; Annals of Clinical Psychiatry, Volume 13, Number 3, September 2001 , pp. 135-140(6)
• Neurological complaints and loss of function caused by nitrous oxide (N2O) anaesthesia, using N₂O acutely causes a dangerous vitamin B12 deficiency.
  ³⁴⁹ Neurologic degeneration associated with nitrous oxide anesthesia in patients with vitamin B12 deficiency. Flippo TS, Holder WD Jr.; Department of General Surgery, Carolinas Medical Center, Charlotte; Arch Surg. 1993 Dec;128(12):1391-5.
  ³⁵⁰ Severe neurologic deficit after nitrous oxide anesthesia. Hadzic A, Glab K, Sanborn KV, Thys DM. Department of Anesthesiology, St. Luke's-Roosevelt Hospital Center, Columbia University College of Physicians and Surgeons, New York, New York 10025, USA; Anesthesiology. 1995 Oct;83(4):863-6.
  ³⁵¹ Postoperative dementia: toxicity of nitrous oxide.El Otmani H, El Moutawakil B, Moutaouakil F, Gam I, Rafai MA, Slassi I.;Service de Neurologie et Explorations Fonctionnelles, CHU Ibn Rochd, Casablanca, Maroc.; Encephale. 2007 Jan-Feb;33(1):95-7.
  ³⁵² Severe polyneuropathy after using nitrous oxide as an anesthetic. A preventable disease. Alarcia R, Ara JR, Serrano M, García M, Latorre AM, Capablo JL.Servicio de Neurología, Hospital Miguel Servet, Zaragoza, España; Rev Neurol. 1999 Jul 1-15;29(1):36-8.
  ³⁵³ Is nitrous oxide a dangerous anesthetic for vitamin B12-deficient subjects?Schilling RF.; JAMA. 1986 Mar 28;255(12):1605-6.
  ³⁵⁴ Subacute combined degeneration of the spinal cord caused by nitrous oxide anaesthesia. Renard D, Dutray A, Remy A, Castelnovo G, Labauge P.; France. dimitrirenard@hotmail.com; Neurol Sci. 2009 Feb;30(1):75-6. Epub 2009 Jan 24. - Subacute combined degeneration caused by nitrous oxide intoxication: case reports.Lin RJ, Chen HF, Chang YC, Su JJ. Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan; Acta Neurol Taiwan. Acta Neurol Taiwan. 2011 Jun;20(2):129-37.
  ³⁵⁵ Reversible nitrous oxide-induced myeloneuropathy with pernicious anemia: case report and literature review. Singer MA, Lazaridis C, Nations SP, Wolfe GI.;Department of Neurology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8897, USA. mike.singer@utsouthwestern.edu; Muscle Nerve. 2008 Jan;37(1):125-9.
• Dementia (including early-onset).
  ³⁵⁶ Blz. 17, 22, 23, 26, 32, 34, 40, 43, 44, 46, 47, 50, 52, 55, 56, 58, 59, 60-65, 67, 69, 70, 79, 81, 88, 89, 101, 102, 105, 108, 112, 113, 115, 132, 140, 171, 177, 178, 184, 192, 193, 208, 212, 217, 222, 226, 229, 255, 257 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁵⁷ Moorthy D, Peter I, [..], Troen AM. Status of Vitamins B-12 and B-6 but Not of Folate, Homocysteine, and the Methylenetetrahydrofolate Reductase C677T Polymorphism Are Associated with Impaired Cognition and Depression in Adults. J Nutr 2012; 142(8):1554-60
  ³⁵⁸ Hooshmand B, Solomon A, [..], Kivipelto M. Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study. Neurology 2010; 75(16):1408-14.
  ³⁵⁹ Haan MN, Miller JW, et al. Homocysteine, B vitamins, and the incidence of dementia and cognitive impairment: results from the Sacramento Area Latino Study on Aging. Am J Clin Nutr 2007; 85(2):511-7.
  ³⁶⁰ Karnaze, Dean S. ~ Low serum cobalamin levels in primary degenerative dementia. (Do some people harbor atypical cobalamin deficiency states?.). Archives of Internal Medicine. 1987; 147: 429 - 431.
  ³⁶¹ Mitsuyama, Y.; Kogoh, H. ~ Serum and cerebrospinal fluid vitamin B12 levels in demented patients with CH-B12 treatment-preliminary 3 study. Japanese Journal of Psychiatry and Neurology. 1988; 42 - 1: 65 - 71.
  ³⁶² Nijst, T.Q.; Wevers, R.A.; Schoonderwaldt, H.C.; e.a. ~ Vitamin B12 and folate concentrations in serum and cerebrospinal fluid of neurological patients with special reference to multiple sclerosis and dementia. Journal of Neurology, Neurosurgery and Psychiatry. 1990; 53: 951 - 945.
  ³⁶³ Roos, D. ~ Various degrees of dementia in a selected group of gastrectomized patients with low serum B12. Acta Neurologica Scandinavica. 1977a; 55: 363 - 376.
  ³⁶⁴ Recurrent reversible jaundice, neuropsychiatric manifestations, dementia and ataxia as manifestations of vit. B12 deficiency.Joshi D, Kumar N, Rai A. J Assoc Physicians India. 2008 Jun;56:475-6.
  ³⁶⁵ Dementia caused by vitamin B12 deficiency. Clinical case.Behrens MI, Díaz V, Vásquez C, Donoso A.Source,Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile; Rev Med Chil. 2003 Aug;131(8):915-9.
  ³⁶⁶ Various degrees of dementia in a selected group of gastrectomized patients with low serum B12.; Roos D, Willanger R;. Acta Neurol Scand. 1977 May;55(5):363-76.
  ³⁶⁷ Dementia: classification and aspects of treatment. Gottfries CG. Sweden; Psychopharmacol Ser. 1988;5:187-95.

Other signs and symptoms

• Tiredness (somnolence), sleepiness, overall weakness; simply no energy, being in bad shape, signs of exhaustion (“waking up tired”). Also related to this: easily brought to tears and getting emotional, no longer being resistant to stress, being stressed out, burned out, exhausted, literally floored. Typical quote from a “vitamin B12 patient”: “I really feel like a geriatric in a young body” (many health complaints that are linked to old age are actually typical vitamin B12 deficiency symptoms).
  ³⁶⁸ Ellis FR, Nasser S. A pilot study of vitamin B12 in the treatment of tiredness. Br J Nutr 1973;30:277-83.
  ³⁶⁹ Blz. 32, 34, 44, 55, 79, 83, 85, 88,152, 164, 186, 191, 211, 217, 218, 222 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Chronic Fatigue Syndrome (CFS)
  ³⁷⁰ Blz. 25, 79, 212 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁷¹ Increased concentrations of homocysteine in the cerebrospinal fluid in patients with fibromyalgia and chronic fatigue syndrome Regland B, Andersson M, Abrahamsson L, Bagby J, Dyrehag LE, Gottfries CG. Scand J Rheumatol. 1997;26(4):301-7.
  ³⁷² Using vitamin B-12 for the management of Chronic Fatigue Syndrome (CFS).Charles W Lapp, M.D. ProHealth.com. February 25, 2000.
  ³⁷³ "One-carbon metabolism and CFS," Regland B et al., presented at The Clinical and Scientific Basis of Chronic Fatigue Syndrome (international symposium), Sydney, Australia, February 1998.
  ³⁷⁴ A pilot study of vitamin B12 in the treatment of tiredness. Ellis FR, Nasser S.  Br J Nutr 1973; 30: 277-283.
  ³⁷⁵ Chronic fatigue syndrome and mitochondrial dysfunction.Myhill S, Booth NE, McLaren-Howard J.; Int J Clin Exp Med. 2009;2(1):1-16
• Fibromyalgia
  ³⁷⁶ Increased concentrations of homocysteine in the cerebrospinal fluid in patients with fibromyalgia and chronic fatigue syndrome Regland B, Andersson M, Abrahamsson L, Bagby J, Dyrehag LE, Gottfries CG. Scand J Rheumatol. 1997;26(4):301-7.
  ³⁷⁷ Myalgic ncephalomyelitis. Simpson LO. J R Soc Med 1991;84:633.
  ³⁷⁸ The rationale for using high-dose cobalamine. Lapp CW, Cheney PR .The CFIDS Chronicle Physicians’ Forum Fall; 1993;19-20.
  ³⁷⁹ Increased concentrations of homocysteine in the cerebrospinal fluid in patients with fibromyalgia and chronic fatigue syndrome. Regland B, Andersson M, Abrahamsson L, Bagby J, Dyrehag LE, Gottfries CG.;Sweden; Scand J Rheumatol. 1997;26(4):301-7.
• Sleepiness (needing a lot of sleep, spontaneously falling asleep), quickly getting tired after (minimal) exertion, and recovering poorly from it.
  ³⁸⁰ Blz. 43, 152, 261 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁸¹ Treatment of recurrent hypersomnia with methylcobalamin (vitamin B12): a case report. Yamada N. Department of Psychiatry, Shiga University of Medical Science, Japan; Psychiatry Clin Neurosci. 1995 Dec;49(5-6):305-7.
  ³⁸² Effect of methylcobalamin (VB12) injection on sleep-wake rhythm in demented patients. Mishima K, Okawa M, Hishikawa Y. Department of Neuropsychiatry, Akita University School of Medicine; Jpn J Psychiatry Neurol. 1992 Mar;46(1):227-8.
  ³⁸³ Central administration of vitamin B12 aggravates cataplexy in canine narcolepsy. Honda K, Riehl J, Inoué S, Mignot E, Nishino S. Sleep Disorders and Research Center, Stanford University, Palo Alto, CA 94304, USA; Neuroreport. 1997 Dec 22;8(18):3861-5.
  ³⁸⁴ Treatment of recurrent hypersomnia with methylcobalamin (vitamin B12): a case report. Yamada, N. Japan. 1995 Dec in Psychiatry and clinical neurosciences.
• Sleepingdisorders
  ³⁸⁵ Ohta, T.; et al ~ Treatment of persistent sleep-wake schedule disorder in adolescents with methylcobalamin (vitamine B12 ). Sleep. 1991a; 14 (5): 414 - 418 & Japanese Journal of Psychiatry and Neurology. 1991b; 45 (1): 167 - 168.
  ³⁸⁶ Okawa, M.; e.a. ~ Vitamin B12 treatment for sleep-wake disorders. Sleep. 1990; 13 (1): 15 - 23.
  ³⁸⁷ Okawa, M.; Mishima, K.; Hishikawa, Y. ~ Vitamine B12 treatment for sleep-wake rhythm disorders. Japanese Journal of Psychiatry and Neurology. 1991; 45 (1): 165 - 166.
  ³⁸⁸ Oku, H. ~ Cyanide with vitamin B12 deficiency as the cause of experimental tobacco amblyopia (niet engelstalig). Nippon Ganka Gakkai Zasshi. 1991; 95: 158 - 164.
  ³⁸⁹ Okuda, K.; e.a. ~ Symposium on role of some of newer vitamins in human metabolism and nutrition, vitamin B12 serum level and pregnancy. American Journal of Clinical Nutrition. 1958; 4: 440 - 443.
• Low or lowered immune system (like with AIDS), which causes a lot of illness, many health complaints, ailments (such as flu-like symptoms). A vitamin B12 deficiency increases susceptibility to infectious diseases in all possible organs.
  ³⁹⁰ Blz. 32-34, 42-44, 47, 71, 72, 79-81, 83, 85, 90, 126, 137, 171, 186, 193, 211, 217, 218, 222, 228, 234, 235, 244, 250, 251, 255, 263, 281, 287, 291 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁹¹ Low serum vitamin B12 concentrations are associated with faster human immunodeficiency virus type 1 (HIV-1) disease progression. Tang A.M. et al. Journal of Nutrition 1997; 127:345-351.
  ³⁹² Low serum cobalamin levels occur frequently in the acquired immune deficiency syndrome and related disorders. Burkes RL, Cohen H, Krailo M, Sinow RM, Carmel R.; Eur J Haematol. 1987 Feb;38(2):141-7.
  ³⁹³ Vitamin B12, cognitive impairment, survival and HHV-6A. No authors listed. Posit Health News. 1998 Spring;(No 16):12-3.
• Fever (with no clear cause).
  ³⁹⁴ Vitamin B12 deficiency presenting as pyrexia. Negi RC, Kumar J, Kumar V, Singh K, Bharti V, Gupta D, Kashyap R, Raina S.Department of Medicine, Indira Gandhi Medical College, Shimla-171001, Himachal Pradesh; J Assoc Physicians India. 2011 Jun;59:379-80.
  ³⁹⁵ Periodic fever responds to vitamin B12 treatment. Naimer S, Volkov I. Israel. Rheumatol Int. 2010 Nov;30(12):1661-3.
  ³⁹⁶ Fever in megaloblastic anemia. McKee LC Jr. South Med J. 1979 Nov;72(11):1423-4, 1428.
• Increased risk of vaginal and urinary tract infections and other infections
  ³⁹⁷ Blz. 28, 44-46, 54, 92, 100, 168, 173, 175, 176, 178, 196, 282 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ³⁹⁸ The Megaloblastic Anemias. Herbert, Victor; Grune and Stratton, 1959b.
  ³⁹⁹ Vitamin B12, folic acid, and the treatment of megaloblastic anemias. Herbert,Victor. In: The pharmacological basis of therapeutics, Goodman, L.S. and Gilman8th. ed. 1990; 1294 - 1302.
  ⁴⁰⁰ Macrocytose, polyneuropathie en achterstrengstoornis door malabsorptie vaneiwitgebonden vitamine B12. Mazure, A.; Bieger, R.; Lambrecht, P.C.L.A.;Wiarda, K.S. Nederlands Tijdschrift voor de Geneeskunde. 1990; 134 (13): 660 -662. En ‘omgekeerd’ werkt Vitamine B12 suppletie
  ⁴⁰¹ Vitamin B12 supplementation improves rates of sustained viral response inpatients chronically infected with hepatitis C virus. Alba Rocco, DeboraCompare, Pietro Coccoli, Ciro Esposito, Antimo Di Spirito, Antonio Barbato,Pasquale Strazzullo, Gerardo Nardone. Gut, July 18, 2012 DOI:10.1136/gutjnl-2012-302344
• Chronic coughing
  ⁴⁰² Vitamin B12 Deficiency is a Common Cause for Chronic Coughing, Dr. David Jockers, www.naturalnews.com; XXI World Allergy Congress (WAC): Abstract 290. Presented December 8, 2009.
  ⁴⁰³ Unexplained chronic cough and vitamin B-12 deficiency.Bucca CB, Culla B, Guida G, Sciascia S, Bellone G, Moretto A, Heffler E, Bugiani M, Rolla G, Brussino L.; Italy. caterina.bucca@unito.it; Am J Clin Nutr. 2011 Mar;93(3):542-8.
• Poor wound healing
  ⁴⁰⁴ Blz. 45, 222 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁰⁶ Effect of vitamin B12 on wound healing. FINDLAY CW Jr.; Proc Soc Exp Biol Med. 1953 Mar;82(3):492-5.
• Asthma, shortness of breath
  ⁴⁰⁷ Blz. 44, 137, 222 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁰⁸ Annibaro B. et al. Journal of Allergy and Clinical Immunology 90(1), p.103, 1992.
  ⁴⁰⁹ Biermer's disease and auto-immune haemolytic anaemia, Nafil H, Tazi I, Mahmal L.; Service d'hématologie, CHU Mohamed VI, Université Cadi Ayyad, Marrakech, Morocco. solhatim@hotmail.comAnn Biol Clin (Paris). 2012 Jul-Aug;70(4):480-2.
  ⁴¹⁰ Hyperhomocysteinaemia and poor vitamin B status in chronic obstructive pulmonary disease. Fimognari FL, Loffredo L, Di Simone S, Sampietro F, Pastorelli R, Monaldo M, Violi F, D'Angelo A.; Italy. filippo.fimognari@virgilio.it ; Nutr Metab Cardiovasc Dis. 2009 Nov;19(9):654-9. Epub 2009 Mar 17.
• Being cold often
  ⁴¹¹ “Eén van mijn klachten is het steeds verschrikkelijk koud hebben. Soms zijn het alleen koude rillingen en voelen m'n ledematen niet eens superkoud aan, maar soms ook ben ik echt door en door koud. De verwarming staat dan flink te loeien en soms zit ik 's avonds op de bank met joggingpak, hempje, t-shirt, sjaal, dikke sokken en heb ik het nog steeds koud”.  Van het forum van www.stichtingb12tekort.nl/forum/index.php?topic=14419.0
  ⁴¹² http://www.fonteine.com/b12_tekort.html
  ⁴¹³ A hot cold man. Frostbite in summer? Polyneuropathy, vitamin B12 deficiency. Urch T.; MMW Fortschr Med. 2010 Jun 17;152(24):5.
• Burning sensation on the skin
  ⁴¹⁴ Blz. 79, 208 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴¹⁵ The critical role of vitamin B12. Volkov I. Phys Sportsmed. Phys Sportsmed. 2008 Dec;36(1):34-41; Department of Family Medicine, Ben-Gurion University of the Negev, Beer-Sheva, 84105, IL. r0019@zahav.net.il.
  ⁴¹⁶ A role for Bâ‚�â‚‚ in inflammatory bowel disease patients with suppurative dermatoses? An experience with high dose vitamin Bâ‚�â‚‚ therapy. Mortimore M, Florin TH. J Crohns Colitis. 2010 Oct;4(4):466-70
  ⁴¹⁷ Homocysteine, vitamin B12 and folic acid levels in psoriatic patients and correlation with disease severity. Brazzelli V, Grasso V, Fornara L, Moggio E, Gamba G, Villani S, Borroni G.;Int J Immunopathol Pharmacol. 2010 Jul-Sep;23(3):911-6.
• Inflammation in the gastrointestinal tract (even including perforated intestines), burping often.
  ⁴¹⁸ Blz. 44, 193, 222, 230 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴¹⁹ Sharma P, Topalovski M, Mayo MS, Sampliner RE, Weston AP. Helicobacter pylori Eradication Dramatically Improves Inflammation in the Gastric Cardia. American Journal of Gastroenterology 2000; 95:3107-3112
• Nausea
  ⁴²⁰ Blz. 26, 203, 204 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴²¹ Neuropsychiatric disorders caused by cobalamine deficiency in the absence of anemia or macrocytosis. Lindenbaum,; e.a. New England Journal of Medicine. 1988; 318: 1720 - 8.
  ⁴²² Small bowel contamination and vitamin B12 deficiency in the elderly. Chesner IM, Montgomery RD. J Clin Gastroenterol. 1986 Aug;8(4):447-50.
• Diminished metabolism
  ⁴²³ Oral vitamin B12 for patients suspected of subtle cobalamin deficiency: a multicentre pragmatic randomised controlled trial. Favrat B, Vaucher P, [..], Verdon F. BMC Fam Pract 2011; 12:2
  ⁴²⁴ Megaloblastic anaemia due to vitamin B12 deficiency caused by small intestinal bacterial overgrowth: possible role of vitamin B12 analogues. Murphy MF, Sourial NA, Burman JF, Doyle DV, Tabaqchali S, Mollin DL.; Br J Haematol. 1986 Jan;62(1):7-12.
• Poor digestion, (pain in the upper abdomen), full or bloated feeling even after eating small or normal portions.
  ⁴²⁵ Blz. 44, 193, 222, 230 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴²⁶ Vitamin B12 deficiency in the elderly. Baik HW, Russell RM. Annu Rev Nutr. 1999;19:357-77.
  ⁴²⁷ Small intestinal bacterial overgrowth in the symptomatic elderly. Riordan SM, McIver CJ, Wakefield D, Bolin TD, Duncombe VM, Thomas MC.Am J Gastroenterol. 1997 Jan;92(1):47-51.
• Less to no appetite
  ⁴²⁸ Blz. 44, 46, 164, 165, 211 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴²⁹ Gastric polyps in pernicious anemia: indications for polypectomy.Rickes S, Gerl H, Lochs H.; Berlin; Dtsch Med Wochenschr. 2000 Sep 8;125(36):1035-8.
  ⁴³⁰ Nutritional megaloblastic anemia in young Turkish children is associated with vitamin B-12 deficiency and psychomotor retardation. Katar S, Nuri Ozbek M, Yaramiş A, Ecer S.; J Pediatr Hematol Oncol. 2006 Sep;28(9):559-62.
  ⁴³¹ Vitamin B12 concentrations in psychiatric patients. Elsborg L, Hansen T, Rafaelsen OJ.; Acta Psychiatr Scand. 1979 Feb;59(2):145-52.
• Gluten intolerance
  ⁴³² Blz. 48, 154, 267 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴³³ Severe anemia in a young woman. Description of a rare coincidence. Kleine G.), Enzkreis-Kliniken, Mühlacker, Germany. guido.kleine@kliniken-ek.de; Dtsch Med Wochenschr. 2007 Jul 30;132(30):1571-4.
  ⁴³⁴ Cobalamine deficiency associated with neuropathy and oral mucosal melanosis in untreated gluten-sensitive enteropathy. Somay G, Cevik DM, Halaç GU, Abut E, Erenoglu NY.;Indian J Gastroenterol. 2005 May-Jun;24(3):120-2.
  ⁴³⁵ Prevalence of hyperhomocysteinemia in adult gluten-sensitive enteropathy at diagnosis: role of B12, folate, and genetics. Saibeni S, Lecchi A, Meucci G, Cattaneo M, Tagliabue L, Rondonotti E, Formenti S, De Franchis R, Vecchi M.; Clin Gastroenterol Hepatol. 2005 Jun;3(6):574-80.
  ⁴³⁶ Vitamin B12 deficiency in untreated celiac disease. Dahele A, Ghosh S.; Vitamin B12 deficiency in untreated celiac disease. Dahele A, Ghosh S.; Am J Gastroenterol. 2001 Mar;96(3):745-50.
• Anorexia
  ⁴³⁷ Blz. 263, 278 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴³⁸ Vitamin deficiency and malnutrition.Birlouez I, Cals MJ, Covi G, Dauvergne A, Faure H, Fayol V, Galabert C, Guéant JL, Guilland JC, Herbeth B, Hercberg S, Jardel A, Jeandel C, Léger C, Le Moël G, Lemoine A, Rousselot D, Thérond P, Vidailhet M.; Ann Biol Clin (Paris). 2002 Jul-Aug;60(4):443-50.
  ⁴³⁹ Idiopathic non-obstructive hypertrophic cardiomyopathy, vitamin B12 deficiency and gastric adenocarcinoma: an unreported association in a teenager. Wolach B, Rothschild M, Pomeranz A, Raz A, Ben Arush M, Rathaus V, Bernheim J, Novis B, Katz S.; Eur J Pediatr. 1998 Sep;157(9):715-8.
  ⁴⁴⁰ Plasma total-homocysteine in anorexia nervosa. Moyano D, Vilaseca MA, Artuch R, Valls C, Lambruschini N.; Eur J Clin Nutr. 1998 Mar;52(3):172-5.
  ⁴⁴¹ Neurologic complications of anorexia nervosa. Patchell RA, Fellows HA, Humphries LL.; Department of Neurology, University of Kentucky Medical Center, Lexington 40536-0084; Acta Neurol Scand. 1994 Feb;89(2):111-6.
  ⁴⁴² Optic neuropathy in a patient with vitamin B12 deficiency: a case report.Areekul S, Roongpisuthipong C, Churdchu K, Thanomsak W.; J Med Assoc Thai. 1992 Dec;75(12):715-8.
  ⁴⁴³ NB:Er is ook sprake van de behandeling van anorexia met behulp van onder andere Vitamine b12: Treatment of infantile anorexia with a combination of reserpine with vitamins B12, B1 and intrinsic factor.ORTEGA CL, MICHELLI JJ.;Sem Med. 1959 Aug 30;l15(Suppl 16):376-81.
• Abdominal pain
  ⁴⁴⁴ Blz. 45, 181 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁴⁵ Primary gastric lymphoma presenting with vitamin B12 deficiency and achlorhydria. Drake WM, Innes DF. Am J Gastroenterol. 1996 Dec;91(12):2605-6.
  ⁴⁴⁶ The relationship between gastric-oral Helicobacter pylori and oral hygiene in patients with vitamin B12-deficiency anemia. Avcu N, Avcu F, Beyan C, Ural AU, Kaptan K, Ozyurt M, Nevruz O, Yalçin A.;Faculty of Dentistry, Department of Oral Diagnosis and Radiology, Hacettepe Universitesi, Ankara, Turkey. aural@gata.edu.tr; Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2001 Aug;92(2):166-9.
  ⁴⁴⁷ Causes of vitamin B12 and folate deficiency. Allen LH. USDA, ARS Western Human Nutrition Research Center, University of California, Davis, CA 95616, USA. lindsay.allen@ars.usda.gov.; Food Nutr Bull. 2008 Jun;29(2 Suppl):S20-34; discussion S35-7.
• Migraine
  ⁴⁴⁸ Functional Vitamin B12 Deficiency Represented by Elevated Urine Methylmalonic Acid Levels in Patients with Migraine. Osman Metin İPÇİOĞLU,Ömer ÖZCAN, Mustafa GÜLTEPE, Hakan TEKELi,Mehmet Güney ŞENOL,E-mail: medsci@tubitak.gov.tr ;Turk J Med Sci. 2008; 38 (5): 409-414.
  ⁴⁴⁹ Unusual association of Arnold-Chiari malformation and vitamin B12 deficiency.Verma R, Praharaj HN.Department of Neurology, Chhatrapati Shahuji Maharaj Medical University, Lucknow, Uttar Pradesh, India; BMJ Case Rep. 2012 Jul 9; 2012.
• Stomach ulcer
  ⁴⁵⁰ Blz. 53, 210 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁵¹ Increased levels of homocysteine in patients with ulcerative colitis. Akbulut S, Altiparmak E, Topal F, Ozaslan E, Kucukazman M, Yonem O. Department of Gastroenterology, Kartal Kosuyolu High Specialty Education and Research Hospital, 34846 Istanbul, Turkey; World J Gastroenterol. 2010 May 21;16(19):2411-6.
  ⁴⁵² Significance of plasmic homocysteine, folate and Vitamin B(12) in ulcerative colitis.Chen ML, Mei Q, Xu JM, Hu NZ, Lu CX, Fang HM.; Zhonghua Wei Chang Wai Ke Za Zhi. 2011 Mar;14(3):185-7 Zhonghua Wei Chang Wai Ke Za Zhi. 2011 Mar;14(3):185-7
• Intestinal complaints, inflammatory bowel disease (IBD)
  ⁴⁵³ Anemia and inflammatory bowel diseases. Gomollón F, Gisbert JP. Gastroenterology Unit, Clinical Universitary Hospital Lozano Blesa, CIBEREHD, Avenida San Juan Bosco 15, Zaragoza 50009, Spain. fgomollon@gmail.com; World J Gastroenterol. 2009 Oct 7;15(37):4659-65.
  ⁴⁵⁴ Prevalence and outcomes of anemia in inflammatory bowel disease: a systematic review of the literature.Wilson A, Reyes E, Ofman J.Zynx Health, Beverly Hills, California 90212, USA; Am J Med. 2004 Apr 5;116 Suppl 7A:44S-49S.
  ⁴⁵⁵ Research progress of anemia associated with inflammatory bowel diseases. Hong ZW, Ren JA. Nanjing University School of Medicine, Nanjing, China; Zhonghua Wei Chang Wai Ke Za Zhi. 2012 Jun;15(6):644-7.
  ⁴⁵⁶ Clinicopathogenetic variants of anemia in patients with intestinal inflammation. No authors listed. Ter Arkh. 2012;84(2):36-41.
  ⁴⁵⁷ Methyl deficient diet aggravates experimental colitis in rats. Chen M, Peyrin-Biroulet L, George A, Coste F, Bressenot A, Bossenmeyer-Pourie C, Alberto JM, Xia B, Namour B, Guéant JL.; Inserm U954, Medical faculty and CHU of Nancy, Nancy-Université, Nancy, France; J Cell Mol Med. 2011 Nov;15(11):2486-97.
  ⁴⁵⁸ Prevalence of anaemia in inflammatory bowel disease in Switzerland: a cross-sectional study in patients from private practices and university hospitals. Voegtlin M, Vavricka SR, Schoepfer AM, Straumann A, Voegtlin J, Rogler G, Ballabeni P, Pittet V, Buser A, Fried M, Beglinger C; Swiss IBD Cohort Study;  J Crohns Colitis. 2010 Dec;4(6):642-8. Epub 2010 Aug 12.
  ⁴⁵⁹ Serum vitamin B12 and folate status in patients with inflammatory bowel diseases. Yakut M, Ustün Y, Kabaçam G, Soykan I.Turkey. musyakut@gmail.com; Eur J Intern Med. 2010 Aug;21(4):320-3. Epub 2010 Jun 8.
  ⁴⁶⁰ Anemia in inflammatory bowel disease. Giannini S, Martes C.; Italy. giannini_simona@libero.it ;Minerva Gastroenterol Dietol. 2006 Sep;52(3):275-91.
  ⁴⁶¹ Blz. 31, 37, 46, 111, 146, 194, 202, 230 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Crohn’s disease
  ⁴⁶² Blz. 30, 48, 111, 154, 179, 194, 195 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁶³ Headstrom PD, Rulyak SJ, Lee SD. Prevalence of and risk factors for vitamin B(12) deficiency in patients with Crohns disease. Inflamm Bowel Dis 2008; 14(2):217-23.
  ⁴⁶⁴ Crohn's disease presenting with recurrent acute polyradiculoneuropathy. El Moutawakil B, Rafai MA, Gam I, Tahiri JM, Rhimou A, Slassi I.Service de Neurologie, CHU Ibn Rochd, Casablanca, Maroc; Rev Neurol (Paris). 2007 Feb;163(2):244-6.
  ⁴⁶⁵ Diagnosis and management of Crohn's disease. Wilkins T, Jarvis K, Patel J.; Georgia Health Sciences University, Augusta, 30912, USA. twilkins@georgiahealth.edu ;Am Fam Physician. 2011 Dec 15;84(12):1365-75. Vitamin B12 deficiency revealing asymptomatic Crohn's disease. Tielman G, Allah-Kouadio E, Guillemot F.;Service d'Hépato-Gastroentérologie, Hôpital Victor Provo, Roubaix. guillaume.tielman@ch-roubaix.fr;
  ⁴⁶⁶ Gastroenterol Clin Biol. 2007 Feb;31(2):195-7.
  ⁴⁶⁷ Megaloblastic anemia in a patient with Crohn's disease. Tamura J, Kubota K, Kurabayashi H, Shirakura T, Sugai Y.; Japan; Rinsho Ketsueki. 1987 Jun;28(6):924-8.
  ⁴⁶⁸ Macrocytic anaemias. Three fifths of patients with Crohn's disease that has not been operated on have vitamin B12 malabsorption. Barton R.; BMJ. 1997 May 24;314(7093):1552.
  ⁴⁶⁹ Vitamin B12 absorption after ileorectal anastomosis for Crohn's disease: effect of ileal resection and time span after surgery. Behrend C, Jeppesen PB, Mortensen PB. Copenhagen, Denmark; Eur J Gastroenterol Hepatol. 1995 May;7(5):397-400.
  ⁴⁷⁰ Direct and quantitative vitamin B12 absorption measurement in patients with disorders in the distal part of the bowel. Comparison of stool spot test [SST] with whole body counting in patients with ileal pelvic reservoir, ileostomy or Crohn's disease. Bayat M, Brynskov J, Dige-Petersen H, Hippe E, Lønborg-Jensen H.; Copenhagen, Denmark; Int J Colorectal Dis. 1994 May;9(2):68-72.
  ⁴⁷¹ Megaloblastic anemia associated with diffuse intestinal Crohn's disease. Abe S, Wakabayashi Y, Hirose S.; Rinsho Ketsueki. 1989 Jan;30(1):51-5.
  ⁴⁷² Pernicious anemia caused by Crohn's disease of the stomach. Kraus J, Schneider R.; Am J Gastroenterol. 1979 Feb;71(2):202-5.
  ⁴⁷³ Remediable defects in Crohn disease: a prospective study of 63 patients. Beeken WL.; Arch Intern Med. 1975 May;135(5):686-90.
  ⁴⁷⁴ Prevalence of and risk factors for vitamin B(12) deficiency in patients with Crohn's disease. Headstrom PD, Rulyak SJ, Lee SD. Inflamm Bowel Dis. 2008 Feb;14(2):217-23.
• Ulcerative colitis
  ⁴⁷⁵ Blz. 48, 181 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁷⁶ Chen M, Mei Q, [..], Liu X. Detection of melatonin and homocysteine simultaneously in ulcerative colitis. Clin Chim Acta 2011.
  ⁴⁷⁷ Dahele A, Ghosh S. Vitamin B12 deficiency in untreated celiac disease.Am J Gastroenterol 2001; 96(3):745-50
  ⁴⁷⁸ Increased levels of homocysteine in patients with ulcerative colitis. Akbulut S, Altiparmak E, Topal F, Ozaslan E, Kucukazman M, Yonem O.;46 Istanbul, Turkey; World J Gastroenterol. 2010 May 21;16(19):2411-6.
  ⁴⁷⁹ Low serum vitamin B12 is common in coeliac disease and is not due to autoimmune gastritis. Dickey W. Eur J Gastroenterol Hepatol. 2002 Apr;14(4):425-7.
• Liver disorders
  ⁴⁸⁰ Serum vitamin B12 levels as indicators of disease severity and mortality of patients with acute-on-chronic liver failure.Dou J, Xu W, Ye B, Zhang Y, Mao W.Clin Chim Acta. 2012 Nov 20;413(23-24):1809-12. Epub 2012 Jul 16.
  ⁴⁸¹ Blz. 29, 30, 112, 119, 230, 241, 246, 261. Lever cirrose: 54, 213. Kanker: 169. “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Diarrhoea (fairly regular).
  ⁴⁸² Blz. 44-46, 176, 222, 287 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁸³ Diarrhea and novel dietary factors emerge as predictors of serum vitamin B12 in Panamanian children. Scatliff CE, Koski KG, Scott ME. Food Nutr Bull. 2011 Mar;32(1):54-9.
  ⁴⁸⁴ Diarrhea with vitamin B12 deficiency. Marteau P, Verkarre V, André C, Brousse N, Cellier C.; Gastroenterol Clin Biol. 2001 May;25(5):495-7.
  ⁴⁸⁵ Malabsorption and deficiency of vitamin B12 in HIV-infected patients with chronic diarrhea.Ehrenpreis ED, Carlson SJ, Boorstein HL, Craig RM.Dig Dis Sci. 1994; Dig Dis Sci. 1994 Oct;39(10):2159-62.
• Kidney failure, renal disorders
  ⁴⁸⁶ Hydroxocobalamin reduces hyperhomocysteinemia in end-stage renal disease. Metabolism. 2002; Elian KM, Hoffer LJ. 51(7):881-6.
  ⁴⁸⁷ Efficacy of methylcobalamin on lowering total homocysteine plasma concentrations in haemodialysis patients receiving high-dose folic acid supplementation. Koyama K, Usami T, Takeuchi O, Morozumi K, Kimura G. Nephrol Dial Transplant 2002 ; 17(5):916-922.
  ⁴⁸⁸ Chronic Renal Failure Promotes Severe Variant of Vitamin B 12 Deficiency; Thomas Duning, Darius Günter Nabavi, Rainer Dziewas, Harald Kugel, Wolf-Rüdiger Schäbitz Eur Neurol 2006;56:62-65.
  ⁴⁸⁹ The kidney in vitamin B12 and folate homeostasis: characterization of receptors for tubular uptake of vitamins and carrier proteins; Henrik Birn Am J Physiol Renal Physiol 291: F22-F36, 2006.
  ⁴⁹⁰ Chronic Renal Failure Promotes Severe Variant of Vitamin B 12 Deficiency; Thomas Duning, Darius Günter Nabavi, Rainer Dziewas, Harald Kugel, Wolf-Rüdiger Schäbitz Eur Neurol 2006;56:62-65.
  ⁴⁹¹ The kidney in vitamin B12 and folate homeostasis: characterization of receptors for tubular uptake of vitamins and carrier proteins; Henrik Birn Am J Physiol Renal Physiol 291: F22-F36, 2006.
• Severe constipation
  ⁴⁹² Blz. 44, 45, 104, 165, 203-205, 222, 261 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁴⁹³ Gastric emptying in patients with vitamin B(12) deficiency. YaÄŸci M, Yamaç K, Acar K, Cingi E, Kitapçi M, Haznedar R.;Eur J Nucl Med Mol Imaging. 2002 Sep;29(9):1125-7.
  ⁴⁹⁴ The status of vitamins B6, B12, folate, and of homocysteine in geriatric home residents receiving laxatives or dietary fiber. Sturtzel B, Dietrich A, Wagner KH, Gisinger C, Elmadfa I.;J Nutr Health Aging. 2010 Mar;14(3):219-23.
  ⁴⁹⁵ Case 4-1970 - Raynaud's Phenomenon, Pyloric Obstruction and Anemia Kurt J. Isselbacher, and Benjamin Castleman; N Engl J Med 1970; 282:211-219January 22, 1970.
• Irregular bowel movements
  ⁴⁹⁶ Antony AC. Megaloblastic anemias. In: Hoffman R, Benz Ej, Shattil SS, et al., eds. Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone;2008:chap 39; www.umm.edu/ency/article/000574sym.htm
• Gas
  ⁴⁹⁷ Antony AC. Megaloblastic anemias. In: Hoffman R, Benz EJ, Shattil SS, et al., eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 39.; www.umm.edu/ency/article/000569.htm
• Weight loss (partly due to diminished appetite).
  ⁴⁹⁸ Blz. 45, 48, 88, 111, 114, 130, 181, 200, 222, 232 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2.
  ⁴⁹⁹ Case records of the Massachusetts General Hospital. Case 13-2012. A 62-year-old man with paresthesias, weight loss, jaundice, and anemia.Puig A, Mino-Kenudson M, Dighe AS.;N Engl J Med. 2012 Apr 26;366(17):1626-33.
  ⁵⁰⁰ Severe vitamin B12 deficiency in infants breastfed by vegans. Roed C, Skovby F, Lund AM.; Ugeskr Laeger. 2009 Oct 19;171(43):3099-101.
  ⁵⁰¹ Vitamin B12 deficiency and severe weight loss in an elderly patient.Gupta NK, Powers JS. Tenn Med. 2008 Feb;101(2):35-6.
  ⁵⁰² Vitamin B12 deficiency. Recognizing subtle symptoms in older adults. Dharmarajan TS, Adiga GU, Norkus EP; Geriatrics. 2003 Mar;58(3):30-4, 37-8. Review.
• Disurbances in taste and/or smell
  ⁵⁰³ Loss of smell and taste within the scope of vitamin B 12 deficiency. Mundt B, Krakowsky G, Röder H, Werner E.; Psychiatr Neurol Med Psychol (Leipz). 1987 Jun;39(6):356-61.
  ⁵⁰⁴ Reversible isolated sensory axonal neuropathy due to cobalamin deficiency.Dalla Torre C, Lucchetta M, Cacciavillani M, Campagnolo M, Manara R, Briani C.; Muscle Nerve. 2012 Mar;45(3):428-30.
  ⁵⁰⁵ Vitamin B12 and homocysteine levels and 6-year change in peripheral nerve function and neurological signs. Leishear K, Ferrucci L, Lauretani F, Boudreau RM, Studenski SA, Rosano C, Abbate R, Gori AM, Corsi AM, Di Iorio A, Guralnik JM, Bandinelli S, Newman AB, Strotmeyer ES.; J Gerontol A Biol Sci Med Sci. 2012 May;67(5):537-43.
• Painful tongue (glossitis), so-called “beefy-red tongue”, especially troublesome with spicy foods and acidic drinks and while brushing teeth, the taste of iron and/or metal in the mouth.
  ⁵⁰⁶ Vitamin B12: an aid to oral mucous membrane healing. Brunson EG, Smith JF, Dixon R.; Oral Surg Oral Med Oral Pathol. 1967 Jul;24(1):102-12.
  ⁵⁰⁷ Gastric polyps in pernicious anemia: indications for polypectomy.Rickes S, Gerl H, Lochs H.; Berlin; Dtsch Med Wochenschr. 2000 Sep 8;125(36):1035-8.
  ⁵⁰⁸ Bijblijven. Cumulatief Geneeskundig Nascholingssyteem. Bloed- en beenmergaandoeningen. Büscher, H.N.; e.a. Jaargang 6, 1990 nummer 3.
  ⁵⁰⁹ Human vitamin B12 deficiency. Baker, S.J. World Review of Nutrition and Dietetics. 1967; 8: 62 - 126.
  ⁵¹⁰ The spectrum of vitamin B12 deficiency. American Family Physician. Clementz, G.L.; Schade, S.G.1990; 41: 150 - 162.
  ⁵¹¹ Glossitis with linear lesions: an early sign of vitamin B12 deficiency. Graells J, Ojeda RM, Muniesa C, Gonzalez J, Saavedra J.J Am Acad Dermatol. 2009 Mar;60(3):498-500.
  ⁵¹² Gastric polyps in pernicious anemia: indications for polypectomy. Rickes S, Gerl H, Lochs H.Dtsch Med Wochenschr. 2000 Sep 8;125(36):1035-8
• Periodontitis, infected gums - leading to other oral health problems.
  ⁵¹³ Folate and vitamin B12 levels in patients with oral lichen planus, stomatitis or glossitis. Thongprasom K, Youngnak P, Aneksuk V.;Southeast Asian J Trop Med Public Health. 2001 Sep;32(3):643-7.
  ⁵¹⁴ Aphthous ulcers and vitamin B12 deficiency.Weusten BL, van de Wiel A.; Neth J Med. 1998 Oct;53(4):172-5.
  ⁵¹⁵ Oral manifestations of vitamin B12 deficiency: a case report. Pontes HA, Neto NC, Ferreira KB, Fonseca FP, Vallinoto GM, Pontes FS, Pinto Ddos S Jr.; J Can Dent Assoc. 2009 Sep;75(7):533-7.  
• Allergies for dust, mould, food, hay fever, certain metals.
  ⁵¹⁶ Case 22-1991 - A 15-Year-Old Boy with Fever of Unknown Origin, Severe Anemia, and Portal-Vein Thrombosis; Podolsky D.K. and Lewandrowski K.B.N Engl J Med 1991; 324:1575-1584
• Epilepsy (West syndrome), epileptic seizures.
  ⁵¹⁷ West syndrome in an infant with vitamin B12 deficiency in the absence of macrocytic anaemia. Erol I, Alehan F, Gümüs A. Division of Child Neurology, Department of Paediatrics, Baskent University Faculty of Medicine, Ankara, Turkey. ilknur_erol@yahoo.com; Dev Med Child Neurol. 2007 Oct;49(10):774-6.
  ⁵¹⁸ Recurrent seizures: an unusual manifestation of vitamin B12 deficiency.Kumar S. Neurol India. 2004 Mar;52(1):122-3.
  ⁵¹⁹ Vitamin B12 deficiency: an unusual cause for recurrent generalised seizures with pancytopaenia. Naha K, Dasari S, Vivek G, Prabhu M.; BMJ Case Rep. 2012 Sep 3;2012 
• Diabetes Mellitus, note: Using the drug Metformin, often prescribed to diabetes patients, may lead to a vitamin B12 deficiency.
  ⁵²⁰ Blz. 48, 51, 54, 58, 59, 76, 127, 130, 132, 133, 136, 148, 158, 181, 203, 208, 210, 212, 226, 236, 251 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵²¹ Het medicijn Metformine, dat heel veel diabeten slikken, veroorzaakt op zichzelf al een Vitamine B12-tekort (www.hln.be). Er zijn ongeveer 800.000 mensen met type 2 diabetes en 70% daarvan gebruikt metformine. Het middel staat in de top-10 van meest voorgeschreven medicijnen. www.spruythillen.nl
  ⁵²² De Jager J, Kooy A, Lehert P, Wulffelé MG, Van der Kolk J, Bets D, et al. Long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B-12 deficiency: randomised placebo controlled trial. BMJ 2010;340:c2181.
  ⁵²³ Sahin M, Tutuncu NB, Ertugrul D, Tanaci N, Guvener ND. Effects of metformin or rosiglitazone on serum concentrations of homocysteine, folate, and vitamin B(12) in patients with type 2 diabetes mellitus. J Diabetes Complications 2007; 21(2):118-23.
  ⁵²⁴ Talaei A, Siavash M, [..], Chehrei A. Vitamin B12 may be more effective than nortriptyline in improving painful diabetic neuropathy. International Journal of Food Sciences and Nutrition 2009; 60(S5):71-76 
  ⁵²⁵  Pflipsen MC, Oh RC, [..], Topolski R. The prevalence of vitamin B(12) deficiency in patients with type 2 diabetes: a cross-sectional study. J Am Board Fam Med 2009; 22(5):528-34.
  ⁵²⁶ Tomkin GH, Hadden DR, Weaver JA, Montgomery DA. Vitamin-B12 status of patients on long-term metformin therapy. Br Med J 1971;2:685-7. * Bauman WA, Shaw S, Jayatilleke E, Spungen AM, Herbert V. Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin. Diabetes Care 2000;23:1227-31.
  ⁵²⁷ DeFronzo RA, Goodman AM. Efficacy of metformin in patients with non-insulin-dependent diabetes mellitus: The Multicenter Metformin Study Group. N Engl J Med 1995;333:541-9.
  ⁵²⁸ Pongchaidecha M, Srikusalanukul V, Chattananon A, Tanjariyaporn S. Effect of metformin on plasma homocysteine, vitamin B12 and folic acid: A cross-sectional study in patients with type 2 diabetes mellitus. J Med Assoc Thai 2004;87:780-7. 
  ⁵²⁹ Wulffelé MG, Kooy A, Lehert P, Bets D, Ogterop JC, Borger van der Burg B, et al. Effects of short-term treatment with metformin on serum concentrations of homocysteine, folate and vitamin B12 in type 2 diabetes mellitus: A randomized, placebo-controlled trial. J Intern Med 2003;254:455-63. 20. 
  ⁵³⁰ Ting RZ, Szeto CC, Chan MH, Ma KK, Chow KM. Risk factors of vitamin B(12) deficiency in patients receiving metformin. Arch Intern Med 2006;166:1975-9.
  ⁵³¹ Vitamin B(12) in type 2 diabetic patients treated with metformin.Calvo Romero JM, Ramiro Lozano JM. Endocrinol Nutr. 2012 Oct;59(8):487-490. doi: 10.1016/j.endonu.2012.06.005. Epub 2012 Sep 13.
  ⁵³² Metformin associated B12 deficiency. Kumthekar AA, Gidwani HV, Kumthekar AB. J Assoc Physicians India. 2012 Mar;60:58-60.PMID: 22799121.
  ⁵³³ Recommendations for diagnosis and management of metformin-induced vitamin B12 (Cbl) deficiency. Mazokopakis EE, Starakis IK.Diabetes Res Clin Pract. 2012 Sep;97(3):359-67. doi: 10.1016/j.diabres.2012.06.001. Epub 2012 Jul 7.
  ⁵³⁴ Status of B-vitamins and homocysteine in diabetic retinopathy: association with vitamin-B12 deficiency and hyperhomocysteinemia. Satyanarayana A, Balakrishna N, Pitla S, Reddy PY, Mudili S, Lopamudra P, Suryanarayana P, Viswanath K, Ayyagari R, Reddy GB. Biochemistry, National Institute of Nutrition, Hyderabad, India. PLoS One. 2011;6(11):e26747. Epub 2011 Nov 1.
  ⁵³⁵ Prevalence of pernicious anaemia in patients with Type 1 diabetes mellitus and autoimmune thyroid disease.Perros P, Singh RK, Ludlam CA, Frier BM.; UK.; Perros@ncl.ac.uk; Diabet Med. 2000 Oct;17(10):749-51.
  ⁵³⁶ Vitamin B12 may be more effective than nortriptyline in improving painful diabetic neuropathy. Talaei A, Siavash M, Majidi H, Chehrei A.;University of Medical Sciences, Arak, Iran; Int J Food Sci Nutr. 2009;60 Suppl 5:71-6. Epub 2009 Feb 11.
• Exocrine Pancreatic Insufficiency (EPI), poorly functioning pancreas, often also caused by an auto-immunity problem.
  ⁵³⁷ Pancreatic Insufficiency and Vitamin B12 Malabsorption.Eugene LeBauer; Kendall Smith; Norton J. Greenberger; Arch Intern Med. 1968;122(5):423-425.
  ⁵³⁸ Malabsorption of vitamin B12 in pancreatic insufficiency of the adult and of the child.Guéant JL, Champigneulle B, Gaucher P, Nicolas JP.;France; Pancreas. 1990 Sep;5(5):559-67.
  ⁵³⁹ Vitamin B12 Malabsorption in Chronic Pancreatic Insufficiency - Studies Suggesting the Presence of a Pancreatic Intrinsic Factor; Phillip P. Toskes, M.D., John Hansell, M.D., James Cerda, M.D., and Julius J. Deren, M.D. N Engl J Med 1971; 284:627-632March 25, 1971.
  ⁵⁴⁰ Vitamin B12 absorption and exocrine pancreatic insufficiency in childhood.Harms HK, Kennel O, Bertele RM, Bidlingmeier F, Böhne A.; Eur J Pediatr. 1981 Mar;136(1):75-9.
• Oral aphthae, vitamin B12 also helps in combating aphthae.
  ⁵⁴⁴ Effectiveness of vitamin B12 in treating recurrent aphthous stomatitis: a randomized, double-blind, placebo-controlled trial. Volkov I, Rudoy I, [..], Press Y. J Am Board Fam Med 2009; 22(1):9-16.
  ⁵⁴⁵ Cyanocobalamin may be beneficial in the treatment of recurrent aphthous ulcers even when vitamin B12 levels are normal.Gulcan E, Toker S, HatipoÄŸlu H, Gulcan A, Toker A.Turkey.drerimgulcan@gmail.com . Am J Med Sci. 2008 Nov;336(5):379-82.
  ⁵⁴⁶ Recurrent aphthae: treatment with vitamin B12, folic acid, and iron. Wray D, Ferguson MM, Mason DK, Hutcheon AW, Dagg JH.; Br Med J. 1975 May 31;2(5969):490-3.
• Acne
  ⁵⁴⁷ Dupre, A.; e.a. ~ Vitamin B12 induced acne. Cutis. 1979; 24: 210 - 211.
  ⁵⁴⁸ Michel, P.L. ~ Un cas d'acné importante du visage consécutive a l'administration de vitamine B12. Bull. Soc. Fr. Dermatol. Syphilol. 1968; 75: 131.
  ⁵⁴⁹ Braun-Falco, O. ~ Problem of vitamin B12 /B12 acne. Selected abstracts. 6 JAMA. 1976b; 235: 1387.
  ⁵⁵⁰ Homocysteine, folic acid and vitamin B12 levels in females with severe acne vulgaris; Arora MK, Seth S, Dayal S.; Clin Chem Lab Med. 2012 May 14.
• Rheumatoid arthritis
  ⁵⁵¹ Blz. 181, 210 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵⁵² Journal of the American College of Nutrition 1994;13(4):351-356.
  ⁵⁵³ B12 Deficiency Myelopathy in a Patient With Long-standing Rheumatoid Arthritis. Bournia VK, Dania V, Lachanis S, Konsta M, Iliopoulos A. J Clin Rheumatol. 2012 Oct;18(7):372-4. doi: 10.1097/RHU.0b013e318273312f.
• Skin diseases and complaints, eczema, red spots, psoriasis, shingles, extremely dry skin, extreme itch.
  ⁵⁵⁴ Blz. 242 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵⁵⁵ Ruedemann, R. ~ Treatment of Psoriasis with large doses of vitamin B12, 1 - 100 mg/cm3. Preliminary clinical Report. Archives of Dermatology and Syphilology. 1954; 69: 738 - 739.
  ⁵⁵⁶ Volkov I, Rudoy I, Freud T, et al. Effectiveness of vitamin B12 in treating recurrent aphthous stomatitis: a randomized, double-blind, placebo-controlled trial. J Am Board Fam Med 2009;22:9-16.
  ⁵⁵⁷ Stucker M, Pieck C, Stoerb C, et al. Topical vitamin B12 - a new therapeutic approach in atopic dermatitis - evaluation of efficacy and tolerability in a randomized placebo-controlled multicentre clinical trial. Br J Dematol 2004;150:977-83.
  ⁵⁵⁸ Low B12 levels in chronic idiopathic urticaria.Mete N, Gulbahar O, Aydin A, Sin AZ, Kokuludag A, Sebik F.; Turkey. nihal_mete@hotmail.com; J Investig Allergol Clin Immunol. 2004;14(4):292-9.
• Noticeable paleness of the face, or a noticeable pale yellow or grey complexion of the skin.
  ⁵⁵⁹ Blz. 211, 282 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵⁶⁰ Reversible cutaneous hyperpigmentation and nails with white hair due to vitamin B12 deficiency. Niiyama S, Mukai H. Dermatol. 2007 Nov-Dec;17(6):551-2. Epub 2007 Oct 19.
  ⁵⁶¹ A pale woman with a gait disorder. Pernicious anemia, vitamin B12 deficiency.Stiefelhagen P.DRK-Krankenhaus Westerwald, D-57627 Hachenburg; MMW Fortschr Med. 2000 Nov 16;142(46):53-4.
• Vitiligo (disappearance of pigment in the skin).
  ⁵⁶² Serum holotranscobalamine, vitamin B12, folic acid and homocysteine levels in patients with vitiligo.Karadag AS, Tutal E, Ertugrul DT, Akin KO, Bilgili SG.Turkey; drayserem@yahoo.com; Clin Exp Dermatol. 2012 Jan;37(1).
  ⁵⁶³ Increased level of serum Homocysteine in vitiligo. Singh S, Singh U, Pandey SS., India. sumanbiotechster@gmail.com; J Clin Lab Anal. 2011;25(2):110-2.
  ⁵⁶⁴ Folic acid and vitamin B12 in vitiligo: a nutritional approach.Montes LF, Diaz ML, Lajous J, Garcia NJ.; Cutis. 1992 Jul;50(1):39-42.
  ⁵⁶⁵ Is there a relationship between homocysteine and vitiligo? A pilot study. Shaker OG, El-Tahlawi SM.Cairo University, Cairo 0123, Egypt. olfatshaker@yahoo.com; Br J Dermatol. 2008 Sep;159(3):720-4. Epub 2008 Jul 4.
  ⁵⁶⁶ Slowly progressive type 1 diabetes mellitus associated with vitiligo vulgaris, chronic thyroiditis, and pernicious anemia. Suzuki C, Hirai Y, Terui K, Kohsaka A, Akagi T, Suda T. Department of Endocrinology, Aomori Prefectural Central Hospital, Aomori.; Intern Med. 2004 Dec;43(12):1183-5. Improvement of vitiligo after oral treatment with vitamin B12 and folic acid and the importance of sun exposure. Juhlin L, Olsson MJ. Sweden; cta Derm Venereol. 1997 Nov;77(6):460-2.
  ⁵⁶⁷ Blz. 44, 48, 164, 181, 210 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  Or:
• Hyperpigmentation, pigment spots, spontaneous bruising.
  ⁵⁶⁸ Skin hyperpigmentation and increased angiogenesis secondary to vitamin B12 deficiency in a young vegetarian woman. Aroni K, Anagnostopoulou K, Tsagroni E, Ioannidis E.; Acta Derm Venereol. 2008;88(2):191-2.
  ⁵⁶⁹ Reversible knuckle hyperpigmentation in B12 deficiency.Kumar V, Sharma V.Department of Nephrology, Postgraduate Institute of Medical Education and Research, Chandigarh, India; N Z Med J. 2011 Sep 9;124(1342):98-9.
  ⁵⁷⁰ Generalized hyperpigmentation of the skin due to vitamin B12 deficiency. Mori K, Ando I, Kukita A. Japan; J Dermatol. 2001 May;28(5):282-5.  Vitamin B12 deficiency: a case report of ongoing cutaneous hyperpigmentation. Hoffman CF, Palmer DM, Papadopoulos D. USA. erderm @aol.com; Cutis. 2003 Feb;71(2):127-30; quiz 138-40. 
  ⁵⁷¹ Blz. 44 en 164 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Dysphasia (problems with speaking, using wrong words, trouble finding the right words, “slurred speech”, “keyboard aphasia”).
  ⁵⁷² Vitamin B12, cognition, and brain MRI measures: a cross-sectional examination. Tangney CC, Aggarwal NT, Li H, Wilson RS, Decarli C, Evans DA, Morris MC.; Neurology. 2011 Sep 27;77(13):1276-82. Erratum in: Neurology. 2011 Nov 8;77(19):1773.
  ⁵⁷³ High frequency of low serum levels of vitamin 12 among patients attending Jordan University Hospital. Barghouti FF, Younes NA, Halaseh LJ, Said TT, Ghraiz SM.; East Mediterr Health J. 2009 Jul-Aug;15(4):853-60.
  ⁵⁷⁴ Vitamin B12 and folate depletion: clinical evidence in a neurological population. Moretti R, Torre P, Antonello RM, Cazzato G, Cattaruzza T, Scapicchio PL.; Neurologist. 2004 Nov;10(6):338-43.
• Hair loss (Alopecia Areata), baldness, hair growing thinner or “rougher”, losing your eyebrows.
  ⁵⁷⁵ A case of vitamin B12 deficiency with broad neurologic disorders and canities. Katsuoka H, Watanabe C, Mimori Y, Nakamura S. Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan; No To Shinkei. 1997 Mar;49(3):283-6.
  ⁵⁷⁶ Serum vitamin B12, folate, ferritin, and iron levels in Turkish patients with alopecia areata. Gonul M, Cakmak SK, Soylu S, Kilic A, Gul U.; Serum vitamin B12, folate, ferritin, and iron levels in Turkish patients with alopecia areata. Indian J Dermatol Venereol Leprol. 2009 Sep-Oct;75(5):552.
• Premature graying of the hair
  ⁵⁷⁷ Blz. 44 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵⁷⁸ Vitamin B12 deficiency: report of a childhood case. Juangbhanit C, Nitidanhaprabhas P, Sirimachan S, Areekul S, Tanphaichitr VS. Department of Pediatrics, Bhumipol Adulyadej Hospital, Donmuang, Bangkok, Thailand; 1991 Jun;74(6):348-54.
  ⁵⁷⁹ Reversible hyperpigmentation of skin and nails with white hair due to vitamin B12 deficiency. Noppakun N, Swasdikul D.; Arch Dermatol. 1986 Aug;122(8):896-9.
• “Unhealthy” brittle nails, split and tear easily.
  ⁵⁸⁰ Pigmentation of fingertips and nails in vitamin B12 deficiency. Ridley CM; Br J Dermatol. 1977 Jul;97(1):105-6.
  ⁵⁸¹ Reversible hyperpigmentation of skin and nails with white hair due to vitamin B12 deficiency. Noppakun N, Swasdikul D. Arch Dermatol. 1986 Aug;122(8):896-9.
  ⁵⁸² Reversible cutaneous hyperpigmentation and nails with white hair due to vitamin B12 deficiency. Niiyama S, Mukai H.; Eur J Dermatol. 2007 Nov-Dec;17(6):551-2
• Neck and/or lower back pain
  ⁵⁸³ Blz 185 IHMB12tekort?
  ⁵⁸⁴ Vitamin B12 in low back pain: a randomised, double-blind, placebo-controlled study; Mauro GL, Martorana U, Cataldo P, Brancato G, Letizia G Eur Rev Med Pharmacol Sci. 2000 May-Jun;4(3):53-8.
  ⁵⁸⁵ Treatment of acute, non-traumatic pain using a combination of diclofenac-cholestyramine, uridine triphosphate, cytidine monophosphate, and hydroxycobalamin.Mibielli MA, Nunes CP, Cohen JC, Scussel AB Jr, Higashi R, Bendavit GG, Oliveira L, Geller M.Brazil; Proc West Pharmacol Soc. 2010;53:5-12.
  ⁵⁸⁶ The efficacy and safety of intramuscular injections of methylcobalamin in patients with chronic nonspecific low back pain: a randomised controlled trial. Chiu CK, Low TH, Tey YS, Singh VA, Shong HK.;bSingapore Med J. 2011 Dec;52(12):868-73.  
• Incontinence
  ⁵⁸⁷ Blz. 43-45, 50, 52, 55, 88, 184, 186, 202-205, 208 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁵⁸⁸ Neurologic aspects of cobalamin deficiency Healton EB, Savage DG, Brust JC, et al.. Medicine (Baltimore) 1991;70:229-45.
  ⁵⁸⁹ Relationship of vitamin B12 deficiency with incontinence in older people.  Rana S, D'Amico F, Merenstein JH. J Am Geriatr Soc 1998;46:931-2.
  ⁵⁹⁰ Masked deficit of vitamin B12 in the patient with heterozygous beta-thalassemia and spastic paraparesis. Bilic E, Bilic E, Zagar M, Juric S.;Department of Pediatric Haematology, University Hospital Centre Zagreb, Croatia. ernest.bilic@zg.htnet.hr; Acta Neurol Belg. 2004 Dec;104(4):173-5.
  ⁵⁹¹ Vitamin B12 deficiency and incontinence in older people. Garcia A, Smith M, Freedman M.; Can J Urol. 2000 Aug;7(4):1077-80.
• Menstruation problems (painful, irregular, sometimes too long, sometimes stays away).
  ⁵⁹² http://www.vitamineabcd.nl/tekort-aan-vitamine-b12
  ⁵⁹³ http://home.hetnet.nl/~hindrikdejong/symptoom.htm
  Remarkable: Vitamin B12 deficiency can also lead to:
• Abnormal PAP-smear results in women, a vitamin B12 deficiency can lead to blood anomalies. These blood anomalies can affect the uterine wall and the cervix. Which can lead to abnormal cell production in the cervix (dysplasia). These can incorrectly be diagnosed as early-stage cervical cancer.
  ⁵⁹⁵ Folate and vitamin B12 levels in abnormal pap smears: a case control study. Yüksel H, Odabasi AR, Cetin G, Eben M, Nergiz S, Onur E.;Eur J Gynaecol Oncol. 2007;28(6):526-30.
  ⁵⁹⁶ Common polymorphisms in methylenetetrahydrofolate reductase gene are associated with risks of cervical intraepithelial neoplasia and cervical cancer in women with low serum folate and vitamin B12. Tong SY, Kim MK, Lee JK, Lee JM, Choi SW, Friso S, Song ES, Lee KB, Lee JP. Cancer Causes Control. 2011 Jan;22(1):63-72.
  ⁵⁹⁸ Blz. 45, 171-173, 181, 211, 222, 251, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Dysplasia (abnormal cell division in the cervix).
  ⁵⁹⁹ Blz. 45, 46, 171-173, 181, 211, 222, 251, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶⁰⁰ Folate and vitamin B12 levels in abnormal pap smears: a case control study. Yüksel H, Odabasi AR, Cetin G, Eben M, Nergiz S, Onur E.;Eur J Gynaecol Oncol. 2007;28(6):526-30.
  ⁶⁰¹ Vitamin B12 status of Thai women with neoplasia of the cervix uteri. Kwanbunjan K, Saengkar P, Cheeramakara C, Tangjitgamol S, Chitcharoenrung K.; Department of Tropical Nutrition and Food Science, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. tmkkb@mahidol.ac.th; outheast Asian J Trop Med Public Health. 2006;37 Suppl 3:178-83.
• Severe menopausal complaints
  ⁶⁰² http://home.kpn.nl/hindrikdejong/relatiemet.htm
  ⁶⁰³ www.hematologienederland.nl/book/export/html/6
• Increased risk of cancer, a vitamin B12 deficiency can lead to an increasingly large amount of damage done to the DNA and alters methylation of the DNA, both factors are known as important factors in cancer risk.
  ⁶⁰⁴ “Vitamin B12 deficiency may lead to an elevated rate of DNA damage and altered methylation of DNA, both of which are important risk factors for cancer” Linus Pauling Institute in de VS. Zie ook: http://lpi.oregonstate.edu/infocenter/vitamins/vitaminB12 .; Dec;36(1):34-41.
  ⁶⁰⁵ Vitamin B12 deficiency reduces proliferation and promotes differentiation of neuroblastoma cells and up-regulates PP2A, proNGF, and TACE. Battaglia-Hsu SF, Akchiche N, Noel N, Alberto JM, Jeannesson E, Orozco-Barrios CE, Martinez-Fong D, Daval JL, Guéant JL. Institut National de la Santé et de la Recherche Médicale U954, Faculté de Médecine, Nancy-Université, F-54505 Vandoeuvre-lès-Nancy, France; Proc Natl Acad Sci U S A. 2009 Dec 22;106(51):21930-5. Epub 2009 Dec 3.
  ⁶⁰⁶ The master key effect of vitamin B12 in treatment of malignancy--a potential therapy?Volkov I. Department of Family Medicine, Faculty of Health Sciences, Ben-Gurion University of the Negev, Lea Imenu St. 59/2, Beer-Sheva 84514, Israel. r0019@zahav.net.il <r0019@zahav.net.il; Med Hypotheses. 2008;70(2):324-8. Epub 2007 Jul 20.
  ⁶⁰⁷ Vitamin B12 could be a "master key" in the regulation of multiple pathological processes. Volkov I, Press Y, Rudoy I.Department of Family Medicine, Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel. r0019@zahav.net.il; J Nippon Med Sch. 2006 Apr;73(2):65-9.
  Note: there is also evidence showing that extra vitamin B12 supplementation inhibits the proliferation of cancer cells.
  ⁶⁰⁸  “The effect of vitamin B12 on the proliferation of malignant cells has been examined in vivo and in vitro in numerous studies. Their results indicate that methylcobalamin inhibits the proliferation of malignant cells and propose the possibility of methylcobalamin as a candidate of potentially useful agents for the treatment for some malignant tumors”. The critical role of vitamin B12. Volkov I. Phys Sportsmed. Phys Sportsmed. 2008 Dec;36(1):34-41; Department of Family Medicine, Ben-Gurion University of the Negev, Beer-Sheva, 84105, IL. r0019@zahav.net.il.  
  ⁶⁰⁹ Effects of methylcobalamin on the proliferation of androgen-sensitive or estrogen-sensitive malignant cells in culture and in vivo. Nishizawa, Y., T. Yamamoto, et al. (1997)  Int J Vit Nutr Res 67(3): 164-170.
  ⁶¹⁰ Methylcobalamin inhibits fibroblast growth factor-8 stimulated proliferation and induces apoptosis in Shionogi carcinoma cells. Goto, G. H., H. Katayama, et al. (2008). Int J Vit Nutr Res 78(1): 21-26.
  ⁶¹¹ The inhibition of some cancers and the promotion of others by folic acid, vitamin B12, and their antagonists. Herbert, Victor. In: Nutritional factors in the induction and maintenance of malignancy. Butterworth, C.E. Jr. and Hutchinson, M.L. New York Academic Press 1983b; 273 - 287. En het meest recente onderzoek: An enzyme-trap approach allows isolation of intermediates in cobalamin biosynthesis. Evelyne Deery, Susanne Schroeder, Andrew D Lawrence, Samantha L Taylor, Arefeh Seyedarabi, Jitka Waterman, Keith S Wilson, David Brown, Michael A Geeves, Mark J Howard, Richard W Pickersgill, Martin J Warren.Nature Chemical Biology, 2012; DOI: 10.1038/nchembio.1086. 
  ⁶¹² Blz. 25, 32, 45-47, 52, 148, 166-173, 175, 181, 186, 210, 242 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Breast cancer Quote: “ there is mounting evidence linking deficient levels of B12 to breast cancer.& rdquo;Pp 22, 146 “Could it be B12?” Sally M. Pacholok and Jeffrey M. Stuart
  ⁶¹³ Choi S-W. Vitamin B12 deficiency: a new risk factor for breast cancer? Nutr Rev. 1999;57(8):250-253
  ⁶¹⁴ Plasma Folate, Vitamin B6, Vitamin B12, Homocysteine, and Risk of Breast Cancer; Shumin M. Zhang, Walter C. Willett, Jacob Selhub, David J. Hunter, Edward L. Giovannucci, Michelle D. Holmes, Graham A. Colditz and Susan E. Hankinson; (e-mail: Shumin.Zhang@channing.harvard.edu); Oxford JournalsMedicine JNCI J Natl Cancer Inst Volume 95, Issue 5Pp. 373-380.
• Stomach cancer, increased risk of
  ⁶¹⁵ Blz. 32, 46, 166, 180 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶¹⁶ De Helicobacter pylori wordt ook in verband gebracht met maagkanker. Een langdurige maagslijmvliesontsteking kan veranderingen in het weefsel veroorzaken. Het maagslijmvlies is dan blijvend veranderd en dat kan op termijn de kans op maagkanker vergroten. Bron: http://www.mlds.nl/ziekten/133/helicobacter-pylori-infectie-met/klachten.
  ⁶¹⁷ Het ernstig last krijgen van de helicobacter pylori wordt in verband gebracht met een Vitamine B12-tekort: Kaptan, Kursad, et al. Helicobacter pylori - Is it a novel causative agent in vitamin B12 deficiency? Archives of Internal Medicine, Vol. 160, May 8, 2000, pp. 1349-53.
  ⁶¹⁸ Stopeck, Alison. Links between Helicobacter pylori infection, cobalamin deficiency, and pernicious anaemia. Archives of Internal Medicine, Vol. 160, May 8, 2000, pp. 1229-30.
  ⁶¹⁹ Pernicious anemia and gastric carcinoid tumor: case report and review. Sculco D, Bilgrami S.;Department of Medicine, University of Connecticut Health Center, Farmington 06062, USA.; Am J Gastroenterol. 1997 Aug;92(8):1378-80.
  ⁶²⁰ Inleiding bloedziekten. Hanen, C; e.a. Stafler, wetenschappelijke uitgeverij, Alphen a/d Rijn, 1979.
• Liver cancer, increased risk of
  ⁶²¹ The Effects of a Primary Nutritional Deficiency (Vitamin B study); Hugh D. Riordan, Nina Mikirova, Paul R. Taylor, Cindy A. Feldkamp, Joseph J. Casciari; Food and Nutrition Sciences, Vol. 3 No. 9, 2012, pp. 1238-1244.
  ⁶²² Rapid appearance of hypomethylated DNA in livers of rats fed cancer-promoting, methyl-deficient diets.Wainfan E, Dizik M, Stender M, Christman JK.New York Blood Center, New York 10021.; Cancer Res. 1989 Aug 1;49(15):4094-7.
• Intestinal cancer, increased risk of
  ⁶²³ Liu Z, Choi SW, [..], Mason JB. Mild depletion of dietary folate combined with other B vitamins alters multiple components of the Wnt pathway in mouse colon. J Nutr 2007; 137(12):2701-8.
  ⁶²⁴ The potential cocarcinogenic effect of vitamin B12 deficiency. Friso S, Choi SW.Department of Clinical and Experimental Medicine, University of Verona School of Medicine, Verona, Italy. simonetta.friso@univr.it; Clin Chem Lab Med. 2005;43(10):1158-63.
  ⁶²⁵ Role of vitamin B12 and folate deficiencies in carcinogenesis.Eto I, Krumdieck CL; Advances in Experimental Medicine and Biology [1986, 206:313-330].
  ⁶²⁶ Vitamin B-12 deficiency induces anomalies of base substitution and methylation in the DNA of rat colonic epithelium. Choi SW, Friso S, Ghandour H, Bagley PJ, Selhub J, Mason JB.Vitamins and Carcinogenesis Laboratory, Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston MA 02111, USA. sang.choi@tufts.edu; J Nutr. 2004 Apr;134(4):750-5.
• Cervical cancer, increased risk of
  ⁶²⁷ Blz. 46, 167, 168, 173 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶²⁸ Yüksel H, Odabasi AR, Cetin G, Eben M, Nergiz S, Onur E. Folate and vitamin B12 levels in abnormal pap smears: a case control study. Eur J Gynaecol Oncol 2007; 28(6):526-30.
  ⁶²⁹ Common polymorphisms in methylenetetrahydrofolate reductase gene are associated with risks of cervical intraepithelial neoplasia and cervical cancer in women with low serum folate and vitamin B12. Tong SY, Kim MK, Lee JK, Lee JM, Choi SW, Friso S, Song ES, Lee KB, Lee JP. Department of Obstetrics and Gynecology, East-West Neo Medical Center, Kyunghee University College of Medicine, Seoul, Korea; Cancer Causes Control. 2011 Jan;22(1):63-72. Epub 2010 Nov 5.
  ⁶³⁰ Lower risk of cervical intraepithelial neoplasia in women with high plasma folate and sufficient vitamin B12 in the post-folic acid fortification era. Piyathilake CJ, Macaluso M, Alvarez RD, Bell WC, Heimburger DC, Partridge EE. Department of Nutrition Sciences, University of Alabama at Birmingham, 1675 University Boulevard, Webb 326, Birmingham, AL 35294, USA. piyathic@uab.edu; Cancer Prev Res (Phila). 2009 Jul;2(7):658-64. Epub 2009 Jun 19.
  ⁶³¹ Vitamin B12 status of Thai women with neoplasia of the cervix uteri. Kwanbunjan K, Saengkar P, Cheeramakara C, Tangjitgamol S, Chitcharoenrung K. Mahidol University, Bangkok, Thailand. tmkkb@mahidol.ac.th; Southeast Asian J Trop Med Public Health. 2006;37 Suppl 3:178-83.
  ⁶³² Diet and premalignant lesions of the cervix: evidence of a protective role for folate, riboflavin, thiamin, and vitamin B12. Hernandez BY, McDuffie K, Wilkens LR, Kamemoto L, Goodman MT. Cancer Research Center of Hawaiibrenda@crch.hawaii.edu; Cancer Causes Control. 2003 Nov;14(9):859-70.
  ⁶³³ Homocysteine, folic acid and B-group vitamins in obstetrics and gynaecology. de la Calle M, Usandizaga R, Sancha M, Magdaleno F, Herranz A, Cabrillo E.Department of Obstetrics and Gynaecology, Hospital La Paz, Paseo de la Castellana n 261, 28046 Madrid, Spain; Eur J Obstet Gynecol Reprod Biol. 2003 Apr 25;107(2):125-34.
• Lung cancer, increased risk of
  ⁶³⁴ Blz. 167, 168 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶³⁵ Localized folate and vitamin B-12 deficiency in squamous cell lung cancer is associated with global DNA hypomethylation.Piyathilake CJ, Johanning GL, Macaluso M, Whiteside M, Oelschlager DK, Heimburger DC, Grizzle WE. Department of Nutrition Sciences, University of Alabama at Birmingham 35294, USA; Nutr Cancer. 2000;37(1):99-107. Nutr Cancer. 2000;37(1):99-107.
• Mouth cancer, increased risk of
  ⁶³⁶ Blz. 167, 168 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶³⁷ Diet and oral premalignancy in female south Indian tobacco and betel chewers: a case-control study. Carley KW, Puttaiah R, Alvarez JO, Heimburger DC, Anantha N.Department of International Health, University of Alabama at Birmingham, Birmingham, AL 35294-0008, USA; Nutr Cancer. 1994;22(1):73-84.
• Infertility among women, increased risk of
  ⁶³⁸ Vitamin B12 deficiency and infertility: report of a case. International Journal of Fertility. Sanfilippo, J.S. 1991; 36: 36 - 38.
  ⁶³⁹ Prevalence of low serum cobalamin in infertile couples. Pront R, Margalioth EJ, [..], Elstein D. Andrologia 2009; 41(1):46-50 .
  ⁶⁴⁰ Vitamin B12 deficiency, infertility and recurrent fetal loss. M Bennett - The Journal of reproductive medicine, 2001 - ncbi.nlm.nih.gov.
  ⁶⁴¹ Cobalamin deficiency and infertility. Menachem Y, Cohen AM, Mittelman M. Am J Hematol. 1994 Jun;46(2):152.
  ⁶⁴² Vitamin B12 deficiency and infertility: report of a case. Sanfilippo JS, Liu YK. Department of Obstetrics and Gynecology, University of Louisville, School of Medicine, Kentucky; Int J Fertil. 1991 Jan-Feb;36(1):36-8.
  ⁶⁴³ Pernicious anemia, vitiligo, and infertility. Gulden KD.Wilkes Family Health Center, North Wilkesboro, NC; J Am Board Fam Pract. 1990 Jul-Sep;3(3):217-20. Ook: blz. 35, 45, 47, 48, 196-200, 202, 222, 229 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2. In dat verband ook te noemen:
• Lower quality sperm in men
  ⁶⁴⁴ Clinical experience with methylcobalamin (CH3-B12) for male infertility. Isoyama R, Kawai S, Shimizu Y, Harada H, Takihara H, Baba Y, Sakatoku J.; Hinyokika Kiyo. 1984 Apr;30(4):581-6.
  ⁶⁴⁵ Clinical experience of methylcobalamin (CH3-B12)/C. citrate combined treatment in male infertility. Isoyama R, Baba Y, Harada H, Kawai S, Shimizu Y, Fujii M, Fujisawa S, Takihara H, Koshido Y, Sakatoku J. Hinyokika Kiyo. 1986 Aug;32(8):1177-83.
  ⁶⁴⁶ Blz. 201, 202 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• (Repeated) miscarriages, increased risk of
  ⁶⁴⁷ Blz. 86, 155, 196, 197, 199, 200, 220 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2)
  ⁶⁴⁸ Vitamin B12 deficiency: Is it underestimated in pregnant women?, Robert H. Glew, Denis M. McCarthy & Dorothy J. Vanderjagt, (Received 26 October 2004; accepted 28 December 2004), ISSN 0001-6349 print/ISSN 1600-0412 online # 2006 Taylor & Francis DOI: 10.1080/00016340500438074.
  ⁶⁴⁹ Bennett M. Vitamin B12 deficiency, infertility and recurrent fetal loss.J Reprod Med. 2001; 46(3):209-12
  ⁶⁵⁰ Hyperhomocysteinemia: a risk factor for placental abruption or infarction. Goddijn-Wessel TAW et al. Eur J Obtetrics, Gynecology, Reproduction & Biology 1996;66:23-29.
  ⁶⁵¹ Vitamin B12 deficiency, infertility and recurrent fetal loss. Bennett M. J Reprod Med. 2001 Mar;46(3):209-12.
  ⁶⁵² Effects of folate and vitamin B12 deficiencies during pregnancy on fetal, infant, and child development. Molloy AM, Kirke PN, Brody LC, Scott JM, Mills JL. School of Medicine, Trinity College Dublin, Ireland. amolloy@tcd.ie; Food Nutr Bull. 2008 Jun;29(2 Suppl):S101-11; discussion S112-5
• Birth defects, increased risk of (for instance neural tube defects, brain injury, spina bifida, congenital heart defect, intrautering growth-retardation).
  ⁶⁵³ Blz. 35, 144, 146, 268 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶⁵⁴ Neural-tube defects are associated with low concentrations of cobalamin (Vitamin B12) in amniotic fluid , M. T. Steen, A. M. Boddie, A. J. Fischer, W. Macmahon, D. Saxe, K. M. Sullivan, P. P. Dembure AND L. J. Elsas Prenat. Diagn. 18: 545-555 (1998)
  ⁶⁵⁵ Vitamin B12 deficiency in children and adolescents, Sonja A. Rasmussen, Paul M. Fernhoff, and Kelley S. Scanlon J Pediatr 2001;138:10-7. 9/19/112160
• Premature birth, increased risk of
  ⁶⁵⁶ Blz. 155 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁶⁵⁷ Terugkerende cystitis. www.uitdaging.net/gezond/vitaminepep.html
  ⁶⁵⁸ www.rightdiagnosis.com/v/vitamin_b12_deficiency/symptoms.htm
• Loss of libido (m/f)
  ⁶⁵⁹ Blz. 44, 45, 102, 202-204, 212 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Erectile dysfunction
  ⁶⁶⁰ Blz. 203-205 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Bulimia (Boulimia nervosa).
  ⁷⁵⁹ Blz. 111, 154, 268 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2 - De kans op een vitamine B12-tekort is drastisch verhoogd bij eetstoornissen. (e.g. boulemie en anorexia)
• All auto-immune diseases are suspect of being associated to a vitamin B12 deficiency.
  ⁶⁶¹ Vitamin B12 and health.Ryan-Harshman M, Aldoori W. FEAST Enterprises, 947 Oshawa Blvd N, Oshawa, ON L1G 5V6. ryanharshman@rogers.com; Can Fam Physician. 2008 Apr;54(4):536-41.
  ⁶⁶² The critical role of vitamin B12. Volkov I.Department of Family Medicine, Ben-Gurion University of the Negev, Beer-Sheva, 84105, IL. r0019@zahav.net.il; Phys Sportsmed. 2008 Dec;36(1):34-41.
  ⁶⁶² Blz. 29, 30, 52, 84, 148, 154, 165, 171, 181, 210 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2 For example:
  Multiple Sclerosis (MS)
  ⁶⁶³ Blz. 17, 21, 25, 26, 43, 52, 78, 79, 83, 85-94, 96-101, 103, 118, 158, 171, 190, 212, 254, 257, 287 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2.
  ⁶⁶⁴ Vitamin B12 metabolism in Multiple Sclerosis; Reynolds E.H.,Bottiglieri T; Laundy M; Crellin RF; Kirker SG Archives of Neurology, 1992 Jun, 49(6):649-52.
  ⁶⁶⁵ Multiple sclerosis and vitamin b12 metabolism; Reynolds EH Journal of neuroimmunology, 1992 oct, 40(2-3):225-30.
  ⁶⁶⁶ Vitamin B12 and its relationship to age of onset of multiple sclerosis; Sandyk R; Auerbuch GI. International Journal of Neuroscience, 1993 Jul-Aug, 71(1-4):93-9.
  ⁶⁶⁷ Vitamin B12, demyelination, remyelination and repair in multiple sclerosis;Miller A, Korem M, Almog R, Galboiz Y. J Neurol Sci 2005 Jun 15;233(1-2):93-7.
  ⁶⁶⁸ Vitamin B12 metabolism and massive-dose methyl vitamin B12 therapy in Japanese patients with multiple sclerosis; Kira J, Tobimatsu S, Goto I Intern Med. 1994 Feb;33(2):82-6.
  ⁶⁶⁹ Vitamin B12 deficiency can mimic multiple sclerosis - report of two cases Iwona Kurkowska-Jastrzebska, Wojciech Wicha, Anna Czlonkowska Case Rep Clin Pract Rev, 2006; 7: 64-68.
  ⁶⁷⁰ Multiple Sclerosis and Vitamin B12 Metabolism [editorial]Reynolds E.H. Journal of Neurology, Neurosurgery and Psychiatry, 1992 may.
  ⁶⁷¹  Nijst, T.Q.; Wevers, R.A.; Schoonderwaldt, H.C.; e.a. ~ Vitamin B12 and folate concentrations in serum and cerebrospinal fluid of neurological patients with special reference to multiple sclerosis and dementia. Journal of Neurology, Neurosurgery and Psychiatry. 1990; 53: 951 - 945.
  ⁶⁷² Arch Neurol 1992;49:649.
  ⁶⁷³ Reynolds, E.H.; e.a. ~ Multiple sclerosis and vitamin B12 deficiency. In: Biomedicine and physiology of vitamin B12. Linnell, J.C.; Bhatt H.R. London, England: Children's Medical Charity. 1990; 121 - 128.
  ⁶⁷⁴ Reynolds, E.H.; e.a. ~ Multiple sclerosis and vitamin B12 metabolism: a new clue. Journal of Neurology, Neurosurgery and Psychiatry. 1988; 51: 739.
  ⁶⁷⁵ Reynolds, E.H.; Linnel, J.C. ~ Vitamin B12 deficiency, demyelination, and multiple sclerosis. Lancet. 17 october 1987; 920.
  ⁶⁷⁶ Reynolds, E.H.; Linnell, J.C. Faludy, J.E.; e.a. ~ Some patients with multiple sclerosis have a disorder of vitamin B12 metabolism. Neurology. 1989; 39 (supplement): 418.
  ⁶⁷⁷ Reynolds, E.H. ~ Multiple sclerosis and vitamin B12 metabolism. Journal of neurology, neurosurgery and psychiatry. 1992a; 55 (5): 339 - 340.
  ⁶⁷⁸ Reynolds, E.H. ~ Vitamin B12 metabolism in multiple sclerosis. Archive of Neurology. 1992b; 49 (6): 649 - 652.
  ⁶⁷⁹ Reynolds, R.R.C.P.; e.a. ~ Multiple sclerosis associated with vitamin B12 deficiency. Archive of Neurology. 1991; 48 (8): 808 - 811.
  ⁶⁸⁰ Unusual association of Arnold-Chiari malformation and vitamin B12 deficiency. Verma R, Praharaj HN. BMJ Case Rep. 2012 Jul 9;2012.
  ⁶⁸¹ Vitamin B12 metabolism and massive-dose methyl vitamin B12 therapy in Japanese patients with multiple sclerosis; J Kira, S Tobimatsu, I Goto - Intern Med, 1994 - life-choice.net.
  ⁶⁸² Functional vitamin B12 deficiency. Turner MR, Talbot K. Department of Neurology, John Radcliffe Hospital, University of Oxford, Oxford, UK; Pract Neurol. 2009 Feb;9(1):37-41.
  ⁶⁸³ J Vitamin B12, demyelination, remyelination and repair in multiple sclerosis. Miller A, Korem M, Almog R, Galboiz Y.Division of Neuroimmunology and Multiple Sclerosis Center, Carmel Medical Center, Haifa 34362, Israel. millera@tx.technion.ac.il; Neurol Sci. 2005 Jun 15;233(1-2):93-7.
  ALS (Amyotrophic Lateral Sclerosis)
  ⁶⁸⁴ Blz. 78, 80, 84, 89, 97 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2

Babies and children

Symptoms listed below are also part of the overall symptoms list, but here references to research that has been done with regards to children are listed.

If a woman has a vitamin B12 deficiency, it is very likely that her baby will also have a vitamin B12 deficiency. Vitamin B12 is passed on during foetal development and through breast milk.

It is estimated that 2 to 5% of all children suffer from a vitamin B12 deficiency. In the Netherlands, that would mean tens of thousands of children. A vitamin B12 deficiency in children can lead to:

• Intrauterine growth restriction
  ⁶⁸⁶ Serum homocysteine level and its association with folic acid and vitamin B12 in the third trimester of pregnancies complicated with intrauterine growth restriction. Gadhok AK, Sinha M, Khunteta R, Vardey SK, Upadhyaya C, Sharma TK, Jha M. Clin Lab. 2011;57(11-12):933-8.
  ⁶⁸⁷ Severe Anaemia during Late Pregnancy. Akhtar M, Hassan I.School of Medicine, Keele University, Staffordshire ST5 5BG, UK; Case Rep Obstet Gynecol. 2012;2012:485452. Epub 2012 Sep 4.
  ⁶⁸⁸ Anemia in pregnancy. American College of Obstetricians and Gynecologists. ACOG Practice Bulletin No. 95: Obstet Gynecol. 2008 Jul;112(1):201-7.
  ⁶⁸⁹ Determinants of Cobalamin Status in Newborns; Guttormsen, Trond Markestad, Einar Solheim and Helga Refsum, Anne-Lise Bjørke Monsen, Per Magne Ueland, Stein Emil Vollset, Anne Berit 2001;108;624-630 Pediatrics.
• Congenital conditions related to neural tube defects (spina bifida).
  ⁶⁹⁰ Maternal serum vitamin B12, folate and homocysteine and the risk of neural tube defects in the offspring in a high-risk area of China. Zhang T, Xin R, [..], Zheng X. Public Health Nutr 2008; juni 12:1-7
  ⁶⁹¹ Maternal vitamin B12 status and risk of neural tube defects in a population with high neural tube defect prevalence and no folic Acid fortification;Molloy AM, Kirke PN, [..], Mills JL. Pediatrics 2009; 123(3):917-23.
  ⁶⁹² Maternal vitamin B12 and the risk of fetal neural tube defects in Egyptian patients. Gaber KR, Farag MK, Soliman SE, El-Bassyouni HT, El-Kamah G. Clin Lab 2007;53(1-2):69-75
  ⁶⁹³ Homocysteine metabolism in pregnancies complicated by neural-tube defects. Mills J. et al. The Lancet 1995;345:149-151.
  ⁶⁹⁴ Neural tube defects and elevated homocysteine levels in amniotic fluid. Steegers-Theunissen RP. American Journal of Obstetrics and Gynecology 1995;172:1439-1441.
  ⁶⁹⁵ Marginal maternal vitamin B12 status increases the risk of offspring with spina bifida. Groenen, P.M.W., Van Rooij, I.A.L.M., Peer, P.G.M., Gooskens, R.H., Zielhuis, G.A. en Steegers-Theunissen, R.P.M. American Journal of Obstetrics and Gynecology; 2004, 191: 7-11.
  ⁶⁹⁶ Reduced vitamin B12 binding by transcobalamin II increases the risk of neural tube defects. Afman, L.A., Van der Put, N.M.J., Thomas, C.M.G., Trijbels, J.M.F. en Blom, H.J.; Q.J.Med. 2001; 94: 159-166.
  ⁶⁹⁷ Vitamin B12 insufficiency and the risk of fetal neural tube defects. Overzichtsartikel: Ray, J.G., Blom, H.J. Q. J. Med. 2003, 96: 289-295.
  ⁶⁹⁸ Neural-tube defects are associated with low concentrations of cobalamin (Vitamin B12) in amniotic fluid; M. T. Steen, A. M. Boddie, A. J. Fischer, W. Macmahon, D. Saxe, K. M. Sullivan, P. P. Dembure AND L. J. Elsas Prenat. Diagn. 18: 545-555 (1998).
  ⁶⁹⁹ Effects of folate and vitamin B12 deficiencies during pregnancy on fetal, infant, and child development. Molloy AM, Kirke PN, Brody LC, Scott JM, Mills JL. School of Medicine, Trinity College Dublin, Ireland. amolloy@tcd.ie; Food Nutr Bull. 2008 Jun;29(2 Suppl):S101-11; discussion S112-5
• Failure to thrive, neurological and motor disorders, dysfunction, paralysis
  ⁷⁰⁰ Graham, S.M., Arvela, O.M. en Wise, G.A., Long term neurologic consequences of nutritional vitamin B12 deficiency in infants. Journal of Pediatrics 1992, 121:710-714.
  ⁷⁰¹ Vitamin B12 deficiency in children and adolescents; Sonja A. Rasmussen, MD, MS, Paul M. Fernhoff, MD, and Kelley S. Scanlon, PhD, RD J Pediatr 2001;138:10-7;
  ⁷⁰² Lampkin, B.; Saunders, E.F. ~ Nutritional vitamin B12 deficiency in an infant. Journal of Pediatrics. 1969; 75: 1053 - 1055.
  ⁷⁰³ Sklar, R. ~ Nutritional vitamin B12 deficiency in a breast-fed infant of a vegan-diet mother. Clinical Pediatrics. 1986; 25: 219 - 221.
  ⁷⁰⁴ Vitamin B12 deficiency in infants secondary to maternal causes. Roumeliotis N, Dix D, Lipson A. CMAJ. 2012 Oct 2;184(14):1593-8. doi: 0.1503/ cmaj.112170. Epub 2012 Jun 18.
  ⁷⁰⁵ Pancytopenia due to vitamin B12 deficiency in a breast-fed infant. Yenicesu I. Faculty of Medicine, Pediatric Hematology, Gazi University, Ankara, Turkey. iyenicesu@hotmail.com; Pediatr Hematol Oncol. 2008 Jun;25(4):365-7.
  ⁷⁰⁶ A child with vitamin B12 deficiency presenting with pancytopenia and hyperpigmentation. Simşek OP, Gönç N, Gümrük F, Cetin M. Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara 06100, Turkey. J Pediatr Hematol Oncol; 2004 Dec;26(12):834-6.
  ⁷⁰⁷ Failure to thrive and psychomotor regression revealing vitamin B12 deficiency in 3 infants.Mathey C, Di Marco JN, Poujol A, Cournelle MA, Brevaut V, Livet MO, Chabrol B, Michel G.Service de Pédiatrie,Centre Hospitalier du Pays d'Aix, avenue des Tamaris, 13616 Aix-en-Provence, France. cmathey@ch-aix.fr; Arch Pediatr. 2007 May;14(5):467-71. Epub 2007 Apr 6.
  ⁷⁰⁸ Cobalamin Status and Its Biochemical Markers Methylmalonic Acid and Homocysteine in different Age Groups from 4 Days to 19 Years; Anne-Lise Bjørke Monsen, Helga Refsum, Trond Markestad, and Per Magne Ueland Clinical Chemistry 49:12 2067-2075 (2003).
  ⁷⁰⁹ Paralysis and pernicious anemia in a young woman. Matrana MR, Gauthier C, Lafaye KM. J La State Med Soc. 2009 Jul-Aug;161(4):228-32.
  ⁷¹⁰ [Megaloblastic-vitamin B12 deficiency anemia in childhood.Mtvarelidze ZG, Kvezereli-Kopadze AN, Kvezereli-Kopadze MA.; Georgian Med News. 2009 May;(170):57-60.
  ⁷¹¹ Megaloblastic anaemia in childhood due to vitamin B12 deficiency, report of 3 cases of congenital selective vitamin B12 malabsorptio.Bienzle U, Olischläger A, Leupold D, Kohne E, Harnisch R, Kleihauer E.; Klin Padiatr. 1976 Mar;188(2):97-103.
  ⁷¹² Neurologic findings of nutritional vitamin B12 deficiency in children. Incecik F, Hergüner MO, Altunbaşak S, Leblebisatan G.;Turk J Pediatr. 2010 Jan-Feb;52(1):17-21.
  ⁷¹³ Vitamin B12 deficiency in a breast fed infant. McPhee AJ, Davidson GP, Leahy M, Beare T.; Arch Dis Child. 1988 Aug;63(8):921-3.
• Mental retardation, delayed learning development
  ⁷¹⁴ Blz. 26, 32, 142, 164, 165, 234,262-266, 270, 271, 273-276, 278, 281, 282, 285, 290 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷¹⁵ Louwman, M., van Dusseldorp, M., van de Vijver, R.J.R. Thomas, C.M.G., Schneede, e.a., Signs of impaired cognitive function in adolescents with marginal cobalamin status. American Journal of Clinical Nitrition 2000, 72: 762-769.
  ⁷¹⁶ Sadowitz, P.D.; e.a. ~ Developmental regression as an early manifestation of vitamin B12 deficiency. Clinical Pediatrics. 1986; 25: 369 - 371.
  ⁷¹⁷ Stolhoff, K.; Schulte, F.J. ~ Vitamin B12 and brain development. Europian Journal of Pediatrics. 1987; 146: 201 - 205.
  ⁷¹⁸ Vitamin B12 and brain development. Stollhoff K, Schulte FJ.; Eur J Pediatr. 1987 Mar;146(2):201-5.
  ⁷¹⁹ Effects of vitamin B12 and folate deficiency on brain development in children.Black MM. USA. mblack@peds.umaryland.edu; Food Nutr Bull. 2008 Jun;29(2 Suppl):S126-31.
  ⁷²⁰ Nutritional deficiency in oral candidosis. Jenkins WM, Macfarlane TW, Ferguson MM, Mason DK.; nt J Oral Surg. 1977 Aug;6(4):204-10.
• No appetite
  ⁷²¹ Blz. 44, 46, 164, 165, 211 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷²² Gastric polyps in pernicious anemia: indications for polypectomy. Rickes S, Gerl H, Lochs H.; Berlin; Dtsch Med Wochenschr. 2000 Sep 8;125(36):1035-8.
  ⁷²³ Nutritional megaloblastic anemia in young Turkish children is associated with vitamin B-12 deficiency and psychomotor retardation. Katar S, Nuri Ozbek M, Yaramiş A, Ecer S.; J Pediatr Hematol Oncol. 2006 Sep;28(9):559-62.
• Epilepsy (West syndrome), epileptic seizures.
  ⁷²⁴ West syndrome in an infant with vitamin B12 deficiency in the absence of macrocytic anaemia. Erol I, Alehan F, Gümüs A. Division of Child Neurology, Department of Paediatrics, Baskent University Faculty of Medicine, Ankara, Turkey. ilknur_erol@yahoo.com; Dev Med Child Neurol. 2007 Oct;49(10):774-6.
  ⁷²⁵ Recurrent seizures: an unusual manifestation of vitamin B12 deficiency.Kumar S. Neurol India. 2004 Mar;52(1):122-3.
  ⁷²⁶ Vitamin B12 deficiency: an unusual cause for recurrent generalised seizures with pancytopaenia. Naha K, Dasari S, Vivek G, Prabhu M.; BMJ Case Rep. 2012 Sep 3;2012
• Hematologic disorders
  ⁷²⁷ Pancytopenia due to vitamin B12 deficiency in a breast-fed infant. Yenicesu I.Faculty of Medicine, Pediatric Hematology, Gazi University, Ankara, Turkey. iyenicesu@hotmail.com; Pediatr Hematol Oncol. 2008 Jun;25(4):365-7.
  ⁷²⁸ Severe vitamin B12 deficiency in a breast fed infant with pancytopenia. Citak FE, Citak EC. Ankara Foundation of Children with Leukemia,Turgutlu Sokak No. 30, Gaziosmanpasa, Ankara, Turkey; J Trop Pediatr. 2011 Feb;57(1):69-70. Epub 2009 Jul 17.
• Apathy
  ⁷²⁹ Effect of vitamin B12 deficiency on neurodevelopment in infants: current knowledge and possible mechanisms. Nutr Rev. 2008 May;66(5):250-5.
• Problems concentrating, difficulties finding words, memory problems
  ⁷³⁰ Concentratieproblemen: Blz. 21, 77, 105, 160 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷³¹ Geheugenproblemen: Blz. 33, 34, 43, 44, 46, 47, 50, 51, 56, 60, 61, 69, 82, 83, 85, 88, 101, 105, 112, 115, 152, 164, 178, 184, 186, 192, 208, 255 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷³² Woordvindingsproblemen: Blz. 143, 158, 159, 162, 164, 261, 262, 263, 271, 278, 281-283 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Lower mental achievement(s)
  ⁷³³ Blz. 33, 51, 60, 85, 164, 178, 192, 208 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷³⁴ Verlaagd IQ, verstandelijke beperking(en): Blz. 260, 264, 277, 278, 285, 290 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷³⁵ Handicaps: Blz. 165, 233, 280 IHMB-tekort?
  ⁷³⁶ Wighton, M.C.; Manson, J.I.; e.a. ~ Brain damage in infancy and dietary vitamin B12 deficiency. Medical Journal of Australia. 1979; 2: 1 - 3.
• Irritability, behavioural issues, impatience, aggression.
  ⁷³⁷ Blz. 115, 158 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷³⁸ Neurologic findings of vitamin B12 deficiency: presentation of 7 cases. Kalayci O, Cetin M, Kirel B, Ozdirim E, Yetgin S, Aysun S, Gurgey A.Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey; Turk J Pediatr. 1996 Jan-Mar;38(1):67-72.;
  ⁷³⁹ Mood disorder with mixed, psychotic features due to vitamin b12 deficiency in an adolescent: case report. Tufan AE, Bilici R, Usta G, ErdoÄŸan A.; Turkey. tevrenus@yahoo.com; Child Adolesc Psychiatry Ment Health. 2012 Jun 22;6(1):25.
• Thyroid disorders
  ⁷⁴⁰ Vitamin B12 absorption and exocrine pancreatic insufficiency in childhood.Harms HK, Kennel O, Bertele RM, Bidlingmeier F, Böhne A.; Eur J Pediatr. 1981 Mar;136(1):75-9
  ⁷⁴¹ Dissociation of the intrinsic factor--vitamin B12 complex by bile: contributing factor to B12 malabsorption in pancreatic insufficiency. Cotter R, Rothenberg SP, Weiss JP.; Scand J Gastroenterol. 1979;14(5):545-50.
• Speech problems (learning to talk occurs much later and not as well as it should), allergies (food, dust, metals, etc.)
  ⁷⁴² Blz. 143, 158, 159, 162, 164, 262, 263, 271, 281-283, 278 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Noticeably pale face
  ⁷⁴³ Ugeskr Laeger. 2011 Aug 22;173(34):2047-8.
• Eczema, skin problems.
  ⁷⁴⁴ Januchowski R. Evaluation of topical vitamin B(12) for the treatment of childhood eczema. J Altern Complement Med 2009; 15(4):387-9
• Toilet-training problems, incontinence.
  ⁷⁴⁵ Blz. 43-45, 50, 52, 55, 88, 184, 186, 202-205, 208 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Cardiac arrhythmia
  ⁷⁴⁶ Low maternal vitamin B12 status during pregnancy is associated with reduced heart rate variability indices in young children. Sucharita S, Dwarkanath P, Thomas T, Srinivasan K, Kurpad AV, Vaz M. Matern Child Nutr. 2012 May 24. doi: 10.1111/j.1740-8709.2012.00418.x
• Loss of strength in arms and legs (sometimes leading to wheelchair use).
  ⁷⁴⁷ Inborn error of vitamin B12 metabolism: a treatable cause of childhood dementia/paralysis. Al Essa M, Sakati NA, Dabbagh O, Joshi S, Al Jishi EA, Rashed MS, Powe JE, Ozand PT. Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia; J Child Neurol. 1998 May;13(5):239-43.
• Severe reaction to vaccinations
  ⁷⁴⁸ Blz. 173, 174, 274, 275 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• ADHD
  ⁷⁴⁹ Blz. 165 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  PDD-NOS
  ⁷⁵⁰ Blz. 160,275 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Autisme
  ⁷⁵¹ Vitamin B12 optic neuropathy in autism.Pineles SL, Avery RA, Liu GT.Neuro-ophthalmology Service, Division of Neuro-Ophthalmology, Hospital of the University of Pennsylvania, Department of Neurology, University of Pennsylvania School of Medicine, 3400 Spruce St, Philadelphia, PA 19104, USA; Pediatrics. 2010 Oct;126(4):e967-70. Epub 2010 Sep 20.
  ⁷⁵² Pilot study of the effect of methyl B12 treatment on behavioral and biomarker measures in children with autism. Bertoglio K, Jill James S, Deprey L, Brule N, Hendren RL. Department of Psychiatry and Behavioral Sciences, University of California, Davis Medical Center, Sacramento, CA, USA; J Altern Complement Med. 2010 May;16(5):555-60
  ⁷⁵³ Blz. 21, 26, 43, 142, 145, 155, 158-162, 164, 165, 200, 212, 219, 233, 256, 259, 265, 266, 272-276, 280, 283-285, 290 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷⁵⁴ www.drneubrander.com Hoe met vitamine B12 Methylcobalamine-injecties (jonge) autistische kinderen in de VS zeer succesvol geholpen worden.
• Abnormal brain CT/MRI/EEG, brain atrophy.
  ⁷⁵⁵ Blz. 65, 66, 143, 179, 182, 260, 263, 265, 269, 279  “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
  ⁷⁵⁶ Vergrote ventrikels, algehele vertraging van hersenactiviteit Blz. 264 “Is het Misschien B12-tekort?” Sally M. Pacholok en Jeffrey M. Stuart. ISBN 978-90-202-0490-2
• Infantile colic
  ⁷⁵⁷ Maternal vitamin B-12 and folate status during pregnancy and excessive infant crying. Goedhart G, van der Wal MF, [..], Bonsel GJ. Early Hum Dev 2011; 87(4):309-14
  ⁷⁵⁸ Gezondheidswetenschapper Geertje Goedhart-de Wolf van het AMC ontdekte dit in 2010; http://www.amc.nl/web/Het-AMC/Nieuws/Nieuwsoverzicht/Nieuws/Etniciteit-legt-gewicht-in-de-schaal.htm Ze stuitte op de link tussen een laag gehalte vitamine B12 bij de moeder en het hebben van een zogenoemde huilbaby. B12 is op meerdere momenten belangrijk tijdens de zwangerschap. Zo speelt deze vitamine een rol bij de rijping van het slaap-waakritme in de hersenen van de baby. Die rijping begint in de baarmoeder en gaat na de geboorte nog enkele maanden door.