"I don't live, I merely survive".

One of the main symptoms of B12 deficiency is fatigue, difficulty with keeping up day to day work, staying fit. Overal unhealthy. Prone to infections (urinary, upper airway). Looking pale, unhealthy. It affects myelin around your nerves, leading to neuropathy. Pains and aches, back, joints, sciatica, also numbness, tingeling, "pins and needles", blurred vision, dizziness. It affects mental wellness, like extreme irritability, anxiety attacks, bipolar and even suicide. Bad concentration, sleep and brainfog.  Can cause muscle weakness. Clumsiness, even to the point one cannot walk anymore. The nerve damage can even get permanent. You can have all kinds of stomach and digestive issues but also severe morning sickness and end up with PPD in pregnancy, and can damage the brain and nerves in the foetus, your baby needs folate and B12 to prevent NTD. Because of the costs of B12 testing no regular testing is done during pregnancy. Bloodlevels are usual within a very wide "normal" range, and doctors look for anemia, to "prove" a deficiency, but neurological symptoms usually proceed long before bloodcells are affected, so the doctor doesn't give you treatment in time. The downward spiral continues year in year out, you feel "off".

 

B12 deficiency, if left untreated, results in death,

Check these patients histories.

 

1. Charlotte her medical negligence case, leading to severe neurological damage, which led her to be bound to a wheelchair.

2. Mother suffering with severe B12 deficiency after using nitrous oxide during 18 hours of labour, which made her bed ridden and it felt like she was going to die, UK.

3. Dr. Andrew Klein: Case study of a midwife with B12 deficiency from helping women in labor who use nitrous oxide against pain.

4. Film of real B12 deficiency case histories of RN Sally Pacholok who works in an E.R. What struck me hard is that a one year old was treated for tongue tie, because he ate badly, but died two weeks later of a severe B12 deficiency, as the autopsy showed, he only breastfed from a long time vegetarian mother.

5. Documentary of patients telling their story and doctors commenting. A peadiatrician who almost died himself of an overlooked B12 deficiency. A young boy in fifth grade who started to have difficulty swallowing food and severely regressed in development from 9 months, but recieved B12 injections too late so ended up being brain damaged.

6. Jimmy's law suit for medical negligence he cannot work as much as he would like from irreversible neurological damage. It runs in his family, but his doctor left it too long even though the guidelines says with neurological symtoms he should have injections every other day.

7. Webinar Dr.Wolffenbuttel, Thyroid and vitamin B12 "partners in crime".

8. Mother of 3 on anti depressants for PPD, severe exhaustion, migraines and backache, not being able to take care anymore of herself and family, in hospital they said she is MHBP and they only found high B12 levels in the blood, but she had to little in her cells, she got better from B12 injections and instead of synthetic folic acid, natural folinic acid (or methylfolate).

9. Peadiatrician explains severe B12 deficiency, Infantile Tremor Syndrome, of breastfed children of mothers of the vegetarian Hindu population.

10. MS patient who improved on B12 injections in this BBC documentary.

 

 

How do you get B12 deficiency?

 

Low B12 you can get from eating little animal food, which is the norm these days, but also from eating predominantly carbodydrates in every meal, which is standard western diet, it simply creates the upper fermenting gut, SIBO, irritable bowl syndrome, your small intestines should be near sterile, but yeast, bacteria and parasites live happily eating your vitamins and minerals. That's why you see people starting a ketogenic diet greatly improve in energy and overal wellbeing. Also stopping grains and dairy sometimes helps. People eliminate until even only meat for a while which can start them a "clean" slate, getting normal gut function. But what also causes low B12 is people who have auto-immune disease, thyroid, stomach, DM1, Coeliac, Crohn's, which leads to malabsorption. Even in children. You can be born with "dirty" genes, not converting or methylating well, 40% of people have the MTHFR gen. ALWAYS AVOID FOLIC ACID FROM FOOD (synthetic) GET METHYLFOLATE OR FOLINIC ACID, the synthetic version folic acid is added to flour and grains in many countries. But also hereditary errors in B12 metabolism. Before it's in your cells, a lot can go wrong. Like with medication, for example the birth control pill, anti-acids, metformin, certain antibiotics and epileptic drugs. Stomach reduction surgery. Everyone knows that laughing gas is a dangerous party drug, because it inactivates your B12 in the cells. But it's used a lot in dentistry and labor. Cancer treatment can cause low B12 levels, it can greatly improve outcomes, B12 is needed to make DNA and RNA. 

 

I am a RN, experienced in the field of a vitamin B12 deficiency.

 

I can help you to connect the dots and get rid of all your misdiagnoses you had, saying "it was all in your head", or medication you got for depression or anxiety. Or "you just have a difficult time", heavy periods, it's pregnancy, being a mother, working fulltime in a tough job, losing loved ones or later in life it's because of menopause you feel miserable. 

 

B12 is very safe, it can not be overdosed or toxic

 

It's water soluble. Even in high doses it is safe, what the body cannot use ends up in the urine.

 

B12 can greatly improve outcomes with the list of symptoms but will tablets be enough?

Tablets may improve some, you can try sublingual in high doses of methylcobalamin and adenosylcobalamin, the natural forms of B12, to see if you feel improvements, if you do, you know it's B12 you are lacking, but having a true problem like not absorbing or metabolising B12 often people need injections for life. Injections need also weeks to months to give improvements, even some years, depending on how deficient you were and how long. Some neurological damage never resolves, key is to start treatment as soon as possible. You're like a dry sponge who needs soaking in pools of B12. If you have low iron and/or folate level, B12 will not help enough. You need normal D, B2, good daily magnesium intake, iodine, molybdenum.  Zinc and copper in the right balance 15 mg zinc/1,5 mg copper for example, and sufficient selenium in food or in the form of selenite in a supplement.

 

What about co-factors

It's not only B12:

Many have too low ferretin (iron), you want your serum level not lower than 30-50 mcg/L and neither have "false high" ferritin because of inflammation, infections or from vigorous excersise. Your Hb (hemoglobin) doesn't go down until really depeleted from ferretine, so Hb can be "normal". Symptoms of low iron: Impaired cognition, fatigue, reduced exercises capacity, restless legs, hairloss. Labs often say below 20 is "normal". And you also need copper for iron to "work".

You need iodine, selenium, molybdenum, active B2, (folate you want 20-45), B6, B1 and al the other minerals and B vitamins. The irony of it all, practically everything you need is in red meat, only C you add, improves heme iron absorption, plant iron like spinach is very hard for the body to get enough from. That's why carnivore diet massively improves so many people, because it's also keto, so it heals the upper fermenting gut.

Getting everything checked at your doctor or a lab in your area is nescessary to know your starting point and to rule out any malignencies. Also a thyroid problem needs to be ruled out, but ranges for TSH are so wide, the doctor usually tells you there's nothing wrong with it. 

Disclaimer

I'm not a medical doctor but have a lot of experience personally and as a RN and IBCLC from 1985 working in hospitals, maternity home care and the last eleven years at the Tongue Tie Clinic where I have gained clinical experience with recognising B12 deficiency and "saved" entire families from the downward spiral of B12 deficiency. 

Who am I

Maaike van Broekhoven RN, IBCLC.
I have worked for last eleven years as a registered nurse and IBCLC Lactation Consultant at the Tongue Tie Clinic in Groningen, the Netherlands. I have been a nurse since 1985, with most of my career spent in maternity home care. I qualified as a Lactation Consultant in 2001.

Throughout my career, I have remained critical of mainstream healthcare and have consistently searched for better, more natural, and more sustainable approaches. I myself was already experiencing many symptoms of B12 deficiency, tried homeopathy and spend thousands on natural approaches and supplements. 

Fourteen years ago, I discovered that my own sons were unable to breastfeed effectively due to tongue ties. This realization led me to research the subject extensively. As a result, I began organizing lectures in the Netherlands and eventually started treating tongue tie in infants with a dentist.

Around six years ago, I learned that I myself had been vitamin B12 deficient for decades. This personal discovery profoundly changed my clinical perspective. Very soon, I noticed a recurring pattern: after tongue-tie release, some parents returned because problems persisted and nothing seemed to help their baby. 

During follow-up consultations, mothers  frequently shared long and complex histories of unexplained symptoms and diagnostic struggles, which often pointed toward unrecognized or inadequately treated B12 deficiency. In follow-up consultations, many mothers described prolonged histories of unexplained neurological, gastrointestinal, or fatigue-related symptoms, often consistent with undiagnosed or inadequately treated B12 deficiency. 

Infants frequently presented with poor suck–swallow coordination, hypotonia or hypertonia, fatigue during feeding, reflux-like symptoms, and suboptimal weight gain and sometimes slow development.

List of symptoms

Neurological:

Absences / seizures
Aphasia (problems with speaking, using the wrong words, not being able to find the right word; “keyboard aphasia”; speaking with a “thick/double tongue,” speech apraxia)
Abnormal reflexes
Ataxia, reduced sense of position (unsteady gait, staggering walk, up to being unable to walk at all)
Concentration and memory problems (no longer able to think clearly, derealization, “cotton wool head,” drowsiness)
Dementia (memory loss)
Dizziness
Fasciculations / myoclonus (like eye muscle twitching, contraction of a small part of a muscle, involuntary movements)
Hearing problems (tinnitus, distorted sound, etc.)
Feeling cold (sometimes also a burning sensation on the skin)
Headache / migraine
Hypertonic bladder (unable to hold urine)
Eye problems (optic neuropathy, blurred vision, visual field loss)
Strange sensation in the feet (feeling like walking on felt, cotton, or cushions; altered surface sensation; burning feeling on the skin)
Restless legs
Muscle pain (worse after exertion than at rest; sometimes cramps, weakness, loss of strength)
Tingling (in the feet and hands, later also in legs, arms, and face; “electric” sensation; “pins and needles”; also numbness in hands and feet, trembling hands, neurological deficits)
Reduced sense of position (unexplained falls or suddenly dropping things)
Heavy and stiff feeling in the legs 

 

Behavioral changes:

Psychological problems (ranging from irritability / “short temper,” mood swings, and unreasonable behavior to severe psychiatric issues, panic attacks, and suicidal behavior)

Other:

Mouth ulcers / inflammation in the mouth

Allergies

Chest tightness / angina-like pain

Spontaneous / unexplained bruising

Anemia

Brittle nails

Digestive issues, diarrhea/constipation (regularly)

Dry skin

Dental problems (inflamed and/or bleeding gums; iron/metallic taste)

Birth defects, neural tube

Yellowing of the skin and whites of the eyes

Weight loss (loss of appetite, loss of taste/smell)

Joint pain

Glossitis (painful tongue, swollen tongue, so-called “beefy tongue,” especially with spicy foods, acidic drinks, and brushing teeth)

Hair loss

Palpitations / heart rhythm disturbances / rapid heart rate

Hyperpigmentation

Impotence

Infections (increased risk of vaginal and urinary tract infections)

Shortness of breath

Loss of libido

Menstrual problems (irregular, sometimes absent)

Miscarriage

Nausea (loss of appetite, vague stomach discomfort, underweight)

Inflammation in the digestive tract (intestinal inflammation, even leading to perforation)

Infertility

Orthostatic hypotension (sudden drop in blood pressure causing dizziness and/or fainting)

Pap smear, false-positive result

Petechiae (red or purple pinpoint skin bleeding)

Pain (including in the back, hands, wrists, hips, and knees)

Sleep problems, insomnia

Drowsiness (also needing a lot of sleep, falling asleep spontaneously)

Fatigue (sometimes very severe, often already upon waking; no energy)

Sinus infections

 

The most common complaints

96% of patients are (unusually) generally fatigued
87% wake up feeling tired
34% have glossitis
30% have hair loss, mouth ulcers, or blurred vision

Neurological complaints

78% suffer from memory loss
75% have poor concentration
73% experience shortness of breath
66% suffer from clumsiness or ataxia
59% experience dizziness
56% have cardiac arrhythmias
50% have aphasia word finding problems

 

Symptoms pregnancy breastfeeding babies and children

Mother B12 deficient ->pregnancy takes 1/3 of reserves, more pregnancies less B12 reserves -> baby born deficient->breastmilk also deficient -> breastfeeding also takes more of the reserves of the mother. Check this story of a mother of three, treated for PPD and severe migraines and extreme back aches and who needed to quit work and lie down often during the day, she went to the hospital and all they saw was a strange high B12 and they said she had MHBP.

Morning sickness, hyperemesis

Anemia but high folic acid intake corrects the megaloblastic anemia.

Neural tube defects
Low birth weight, small skull, underdeveloped brain tissue
Frequent crying, hypersensitivity
Weakened sucking and swallowing reflexes
Not smiling, no longer smiling
Developmental delay or regression after initial progress (due to breastfeeding-deficient mother)

Prone to infections mother and baby
Apathy

Sleep problems, insomnia
Hyperirritability, convulsions
General weakness
Crying a lot, crying baby
Abnormal movements (arms and legs), involuntary movements,ataxia
Insulin resistance

"Breastfeeding" icterus

Breastfeeding/ bottle problems, difficulty keeping vacuum at breast or bottle, people go for tongue tie release which doesn't help. Baby still drinks too little, even seems not hungry sometimes. Spitting, reflux. Refusing being fed. Refusing weaning. Refusing bottle instead of breast. Falls asleep while feeding.

Regurgitation, (silent) reflux

Hyperactive gagging reflex

Insufficient weight gain. Sometimes head circumference too small.
Anorexia

Reflexes that should disappear, stay longer

Also midwives can get B12 deficient helping mothers in labor with gas and air, check this case.

Mothers exhausted, "dying", needing extra help looking after themselves and the baby, check this mother who was bedridden.

 

 

Symptoms in children, adolescents:

Behavioral problems (mild to severe)
Depression (mild to severe)
Cognitive decline (memory, concentration problems)
Nausea, loss of appetite
Growth problems

Check this documentary of real case histories
 

 

Misdiagnosis your doctor thinks you have:

FND FNS, Functional Neurological Disorder/syndrome 

SCD, subacute combined degeneration of the spinal cord.

Small intestinal bacterial overgrowth, SIBO Irritable Bowl Syndrome

Bipolar, (Post partum) Depression/ Psychosis, MHBP in mothers

Anxiety, Panic attack, PTSS post traumatic stress syndrome (with the heart palpitations for example)

"There's no aneamia, so you cannot be B12 deficient". Neurological and psychiatric symptoms very often proceed aneamia.

Fibromialgia, CFS chronic fatigue syndrome, Long Covid, Burn out, ME, MS. PAIS; Post Acute Infections Syndromes Like Covid or Lyme, biggest symptom is PEM; Post Exertional Malaise en POTS (dizziness on getting up).

ADHD, Autisme, attention disorders, behavioural disorders.

Failure to thrive, developmental delay.

 

 

Treatment your doctor thinks you should have:

Tablets, which don't work when you have malabsorption, it doesn't end up in your cells (neuropathy gets worse).

Injections, which they limit because your bloodlevels get "too high". Generally doctors do not observe the patient, they only look at bloodlevels. Or stop during pregnancy and breastfeeding (when you need them even more). Or because the NICE guidelines says every three months after a "loading dose"of only 10 injections. Although they have improved in 2025 the fact that in case of neurological symptoms, treatment with injections should be started, regardless of "normal" bloodlevels. And in case of little or not enough improvements more injections should be offered. So taking the NICE guidelines to your doctor is worth trying.

 

Which treatment you should you have:

Frequent injections until symptoms subside, only then frequency should not be lowered. Twice a week is the minimum for neuropathy for two years. Sometimes even daily. Patients need to learn to self inject, so they are not dependant of the GP office to give it to them whenever they think you can have it. Unlimited prescriptions. During pregnancy and breastfeeding B12 injections should not be stopped, the need is even higher.

 

What is reality:

Patients get only tablets. Or injections are stopped when blood levels are high, while the patient still suffers. Or in pregnancy the injections are stopped.

Patients get limited injections due to the NICE guidelines, although they have improved in 2025 the fact that in case of neurological symptoms, treatment with injections should be started, regardless of "normal" bloodlevels. And in case of little or not enough improvements more injections should be offered. So taking the NICE guidelines to your doctor is worth trying.

Patients end up having to buy injections themselves. Syringes and needles.

Sometimes it is difficult for patients to get the right information, but it is possible and also affordable for most people. 

 

What if it really goes wrong, medical negligance cases won:

Hopefully your GP, internist or heamatologist or neurologist or peadiatrican or gyneacologist is familiar with B12 deficiency and can help you to get proper treatment in time and guidance. But there have been numerous cases where the doctors did not take the patient seriously. Here's the story of Charlotte who can no longer walk, they said "it was all in her head", as she was on anti depressants, a true other sign of B12 deficiency, and became numb from the waist down. She won. Here's another case of Jimmy, he also won.

 

Where can I get more help:

Hopefully your GP, internist or heamatologist is familiar with B12 deficiency and can help you to get proper treatment and guidance.

Patientgroups are there to help people to get further when you get stuck. Patientgroups on Facebook, Whatsapp etc.

You can contact me if you want more information and guidance also to learn how to self inject, just like if you had diabetes, it is not difficult. I am located in The Netherlands and Spain.

 

 

B12 is not a hype or alternitive medicin,

it is evidence based medicin.

References, literature, case studies, research:

1. Wolffenbuttel BHR, McCaddon A, Ahmadi KR, Green R. A Brief Overview of the Diagnosis and Treatment of Cobalamin (B12) Deficiency. Food and Nutrition Bulletin. 2024;45(1_suppl):S40-S49. doi:10.1177/03795721241229500 Wolffenbuttel BH, Owen PJ, Ward M, Green R. Vitamin B12. BMJ. 2023;383:e071725. doi:10.1136/bmj-2022-071725
2. Honzik T, Adamovicova A, Smolka V, Magner M, Hruba E, Zeman J. Clinical presentation and metabolic consequences in 40 breastfed infants with nutritional vitamin B12 deficiency – What have we learned? Eur Jour Ped Neurol 14 (2010) 488–495Hartmann, HansLücke, Thomas et al. European Journal of Paediatric Neurology, Volume 15, Issue 4, 377
3. *78 Mills JL, Molloy AM, Reynolds EH. Do the benefits of folic acid fortification outweigh the risk of masking vitamin B₁₂ deficiency? BMJ. 2018 Mar 1;360:k724. doi: 10.1136/bmj.k724. Erratum in: BMJ. 2018 Mar 21;360:k1334. doi: 10.1136/bmj.k1334. PMID: 29496696; PMCID: PMC6889897.
4. Graydon JS, Claudio K, Baker S, Kocherla M, Ferreira M, Roche-Lima A, Rodríguez-Maldonado J, Duconge J, Ruaño G. Ethnogeographic prevalence and implications of the 677C>T and 1298A>C MTHFR polymorphisms in US primary care populations. Biomark Med. 2019 Jun;13(8):649-661. doi: 10.2217/bmm-2018-0392. Epub 2019 Jun 3. PMID: 31157538; PMCID: PMC6630484.
5. Saravanan, P., Sukumar, N., Adaikalakoteswari, A. et al. Association of maternal vitamin B₁₂ and folate levels in early pregnancy with gestational diabetes: a prospective UK cohort study (PRiDE study). Diabetologia 64, 2170–2182 (2021). https://doi.org/10.1007/s00125-021-05510-7
6. Eline Stoutjesdijk Brain-selective nutrients in pregnancy and lactation. RUG 2020,
7. The vitamin B12 intakes of a substantial proportion of Australian women of reproductive age consuming a vegan diet do not meet the recommended intake, which could adversely affect their health, and, if they are pregnant or lactating, that of their infants too. https://pubmed.ncbi.nlm.nih.gov/33875034/
8. (UMFA) 2018 study by Wiens et al. in American Journal of Clinical Nutrition found that high maternal UMFA levels during pregnancy were associated with altered DNA methylation patterns in offspring, potentially affecting neurodevelopment (Wiens, D., et al., 2018, American Journal of Clinical Nutrition, 108(6), 1289-1297).
9. Tucker KL, Rich S, Rosenberg I, et al. Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring Study. The American Journal of Clinical Nutrition. February 1, 2000 2000;71(2):514-522.
10. Sedel F, Baumann N, Turpin JC, Lyon-Caen O, Saudubray JM, Cohen D. Psychiatric manifestations revealing inborn errors of metabolism in adolescents and adults. 10.1007/s10545-007-0661-4. J Inher Metab Dis. 2007;30:631-641.
11. Lai JS, Mohamad Ayob MN, Cai S, et al. Maternal plasma vitamin B12 concentrations during pregnancy and infant cognitive outcomes at 2 years of age. Br J Nutr. Apr 2 2019:1-26. doi:10.1017/S0007114519000746
12. Malhotra S, Subodh BN, Parakh P, Lahariya S. Brief report: Childhood disintegrative disorder as a likely manifestation of vitamin b12 deficiency. Journal of Autism and Developmental Disorders. 2013;doi:10.1007/s10803-013-1762-6
13. Monagle PT, Tauro GP. Infantile megaloblastosis secondary to maternal vitamin B12 deficiency. Clinical & Laboratory Haematology. 1997;19(1):23-25. doi:10.1046/j.1365-2257.1997.00205.x

14.   Rasmussen SA, Fernhoff PM, Scanlon KS. Vitamin B₁₂ deficiency in children and adolescents. The Journal of Pediatrics. 2001;138(1):10-17. doi:10.1067/mpd.2001.112160

15. Refsum H. Folate, vitamin B12 and homocysteine in relation to birth defects and pregnancy outcome. 10.1049/BJN2000302. British Journal of Nutrition. 2001;85(Supplement S2):S109-S113
16. Sole-Navais P, Cavalle-Busquets P, Fernandez-Ballart JD, Murphy MM. Early pregnancy B vitamin status, one carbon metabolism, pregnancy outcome and child development. Biochimie. Jul 2016;126:91-6. doi:10.1016/j.biochi.2015.12.003
17. Torsvik I, Ueland PM, Markestad T, Bjørke-Monsen A-L. Cobalamin supplementation improves motor development and regurgitations in infants: results from a randomized intervention study. The American Journal of Clinical Nutrition. November 1, 2013 2013;98(5):1233-1240. doi:10.3945/ajcn.113.061549
18. Green R, Allen LH, Bjørke-Monsen A-L, et al. Vitamin B12 deficiency. Primer. 06/29/online 2017;3:17040. doi:10.1038/nrdp.2017.40
19. Hunt A, Harrington D, Robinson S. Vitamin B12 deficiency, Clinical review. Journal Article. 2014-09-04 10:56:04 2014;349doi:10.1136/bmj.g5226
20. Hannibal L, Lederer A-K, Storz MA, Huber R, Jacobsen DW. Vitamin B12 Status and Supplementation in Plant-Based Diets. Food and Nutrition Bulletin. 2024;45(1_suppl):S58–S66. doi:10.1177/03795721241227233
21. Osborne D, Sobczyńska-Malefora A. Autoimmune mechanisms in pernicious anaemia & thyroid disease. Autoimmunity Reviews. 9// 2015;14(9):763-768. doi:http://dx.doi.org/10.1016/j.autrev.2015.04.011
22. Webinar Thyroid and vitamin B12, “partners in crime”. Dr. Bruce Wolffenbuttel.  https://youtu.be/JTbCahQ7YfA?si=ChTisZxaEM3Y1ffi
23. Stabler SP. Vitamin B12 Deficiency. New England Journal of Medicine. 2013;368(2):149-160. doi:doi:10.1056/NEJMcp1113996
24. Solomon LR. Vitamin B12-responsive neuropathies: A case series. Nutritional Neuroscience. 2016/04/20 2016;19(4):162-168. doi:10.1179/1476830515Y.0000000006
25. Solomon LR. Disorders of cobalamin (Vitamin B12) metabolism: Emerging concepts in pathophysiology, diagnosis and treatment. Blood Reviews. 2007;21(3):113-130. doi:http://dx.doi.org/10.1016/j.blre.2006.05.001
26. Eroglu N, Kandur Y, Kalay S, Kalay Z, Guney O. Neonatal Hyperbilirubinemia in a Turkish Cohort: Association of Vitamin B12. Journal of Clinical Medicine Research. 2015;7(7):556-559. doi:10.14740/jocmr2158w
27. Gold R, Bogdahn U, Kappos L, et al. Hereditary defect of cobalamin metabolism (homocystinuria and methylmalonic aciduria) of juvenile onset. 10.1136/jnnp.60.1.107. J Neurol Neurosurg Psychiatry. 1996;60:107-108
28. Huemer M, Kozich V, Rinaldo P, et al. Newborn screening for homocystinurias and methylation disorders: systematic review and proposed guidelines. J Inherit Metab Dis. Mar 12 2015;doi:10.1007/s10545-015-9830-z
29. Pluvinage JV, Ngo T, Fouassier C, et al. Transcobalamin receptor antibodies in autoimmune vitamin B12 central deficiency. Sci Transl Med. Jun 26 2024;16(753):eadl3758. doi:10.1126/scitranslmed.adl3758. Ermens AA, Vlasveld LT, van Marion-Kievit JA, Lensen CJ, Lindemans J. The significance of an elevated cobalamin concentration in the blood. Ned Tijdschr Geneeskd. 2002 Mar 9;146(10):459-64. Dutch. PMID: 11913109.
30. Armour CM, Brebner A, Watkins D, Geraghty MT, Chan A, Rosenblatt DS. A patient with an inborn error of vitamin B12 metabolism (cblF) detected by newborn screening. Pediatrics. 2013 Jul;132(1):e257-61. doi: 10.1542/peds.2013-0105. Epub 2013 Jun 17. PMID: 23776111.
31. Huemer M, Kozich V, Rinaldo P, et al. Newborn screening for homocystinurias and methylation disorders: systematic review and proposed guidelines. J Inherit Metab Dis. Mar 12 2015;doi:10.1007/s10545-015-9830-z
32. MacFarlane AJ, Greene- Finestone LS, Shi Y. Vitamin B- 12 and homocysteine status in a folate- replete population: results from the Canadian Health Measures Survey. Am J Clin Nutr 2011;94:1079–87
33. The prevalence and clinical relevance of hyperhomocysteinemia suggesting vitamin B12 deficiency in presumed healthy infants https://pubmed.ncbi.nlm.nih.gov/34717141/
34. Helga Refsum et al, Screening for Serum Total Homocysteine in Newborn Children Clinical Chemistry, Volume 50, Issue 10, 1 October 2004, Pages 1769–1784
35. Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring study. https://pubmed.ncbi.nlm.nih.gov/10648266/
36. Molloy AM, Kirke PN, Troendle JF, Burke H, Sutton M, Brody LC, Scott JM, Mills JL. Maternal vitamin B12 status and risk of neural tube defects in a population with high neural tube defect prevalence and no folic Acid fortification. Pediatrics. 2009 Mar;123(3):917-23. doi: 10.1542/peds.2008-1173. PMID: 19255021; PMCID: PMC4161975
37. Wang, J.; Lv, S.; Chen, G.; Gao, C.; He, J.; Zhong, H.; Xu, Y. Meta-Analysis of the Association between Vitamin D and Autoimmune Thyroid Disease. Nutrients 2015, 7, 2485-2498. https://doi.org/10.3390/nu7042485
38. Latitude continues to be significantly associated with the prevalence of multiple sclerosis: an updated meta-analysis https://jnnp.bmj.com/content/90/11/1193.long
39. The latitude gradient for multiple sclerosis prevalence is established in the early life course. Clive E Sabel , John F Pearson , Deborah F Mason , Ernest Willoughby , David A Abernethy , Bruce V Taylor Author NotesBrain, Volume 144, Issue 7, July 2021, Pages 2038–2046, https://doi.org/10.1093/brain/awab104
40. Lukina P, Andersen IL, Klaasen RA, Warren DJ, Bolstad N, Mjønes P, Rønne E, Iversen R, Sollid LM, Lundin KEA, Ness-Jensen E. The Prevalence and Rate of Undiagnosed Celiac Disease in an Adult General Population, the Trøndelag Health Study, Norway. Clin Gastroenterol Hepatol. 2024 Jul 8:S1542-3565(24)00602-5. doi: 10.1016/j.cgh.2024.06.027. Epub ahead of print. PMID: 38987013.
41. Mathey C, Di Marco JN, Poujol A, Cournelle MA, Brevaut V, Livet MO, Chabrol B, Michel G [Failure to thrive and psychomotor regression revealing vitamin B12 deficiency in 3 infants]. Arch Pediatr. 2007 May;14(5):467-71. French. doi: 10.1016/j.arcped.2007.01.014. Epub 2007 Apr 6. PMID: 17412572.
42. McLeod DSA, Cooper DS. The incidence and prevalence of thyroid autoimmunity. Endocrine 2012;42:252–65.
43. Ness- Abramof R, Nabriski DA, Braverman LE, etal. Prevalence and evaluation of B12 deficiency in patients with autoimmune thyroid disease. Am J Med Sci 2006;332:119–22
44. MacFarlane AJ, Greene- Finestone LS, Shi Y. Vitamin B- 12 and homocysteine status in a folate- replete population: results from the Canadian Health Measures Survey. Am J Clin Nutr 2011;94:1079–87.
45. Mathey C, Di Marco JN, Poujol A, Cournelle MA, Brevaut V, Livet MO, Chabrol B, Michel G [Failure to thrive and psychomotor regression revealing vitamin B12 deficiency in 3 infants]. Arch Pediatr. 2007 May;14(5):467-71. French. doi: 10.1016/j.arcped.2007.01.014. Epub 2007 Apr 6. PMID: 17412572
46. https://www.ntvg.nl/system/files/publications/2006104650001a.pdf
47. Smolka V, Bekárek V, Hlídková E, Bucil J, Mayerová D, Skopková Z, Adam T, Hrubá E, Kozich V, Buriánková L, Saligová J, Buncová M, Zeman J. Metabolické komplikace a neurologické projevy pri deficitu vitaminu B12 u dĕtí vegetariánských matek [Metabolic complications and neurologic manifestations of vitamin B12 deficiency in children of vegetarian mothers]. Cas Lek Cesk. 2001 Nov 22;140(23):732-5. Czech. PMID: 11787236.
48. Azad C, Jat KR, Kaur J, et al. Vitamin B12 status and neurodevelopmental delay in  Indian infants: a hospital- based cross- sectional study. Paediatr Int Child Health  2020;40:78–84
49. Goraya JS, Kaur S. Infantile tremor syndrome: A review and critical appraisal of its etiology. J Pediatr Neurosci. 2016 Oct-Dec;11(4):298-304. doi: 10.4103/1817-1745.199475. PMID: 28217150; PMCID: PMC5314841.
50. Goraya JS, Kaur S, Mehra B. Neurology of Nutritional Vitamin B12 Deficiency in Infants: Case Series From India and Literature Review. J Child Neurol. 2015 Nov;30(13):1831-7. doi: 10.1177/0883073815583688. Epub 2015 May 7. PMID: 25953825
51. Retardation of myelination due to dietary vitamin B12 deficiency, cranial MRI findings K.-O. Lovblad ( L. Remonda C. Ozdoba • G. Schroth Department of Neuroradiology, University of Bern Pediatr Radio! (1997) 27: 155-158
52. Refusal_to_eat_solids_growth_failure_and_developmental_regression_in_a_breastfed_infant November 2024 BMJ Case Reports 17(11):e262339 DOI:10.1136/bcr-2024-262339
53. An Implicit Cause of Prolonged Neonatal Jaundice: Vitamin B12 Deficiency, Erhan Aygun et al.  https://d-nb.info/1283587440/34
54. Severe vitamin B12 deficiency presenting with hemolytic anemia case study. https://bmjpaedsopen.bmj.com/content/8/Suppl_5/A89.3
55. Eroglu N, Kandur Y, Kalay S, Kalay Z, Guney O. Neonatal hyperbilirubinemia in a Turkish cohort: association of vitamin B12. J Clin Med Res. 2015 Jul;7(7):556-9. doi: 10.14740/jocmr2158w. Epub 2015 May 8. PMID: 26015822; PMCID: PMC4432899.
56. Chalouhi C, Faesch S, Anthoine-Milhomme MC, Fulla Y, Dulac O, Chéron G. Neurological consequences of vitamin B12 deficiency and its treatment. Pediatr Emerg Care. 2008 Aug;24(8):538-41. doi: 10.1097/PEC.0b013e318180ff32. PMID: 18708898
57. Calcaterra V, Montalbano C, Miceli E, Luinetti O, Albertini R, Vinci F, Regalbuto C, Larizza D. Anti-gastric parietal cell antibodies for autoimmune gastritis screening in juvenile autoimmune thyroid disease. J Endocrinol Invest. 2020 Jan;43(1):81-86. doi: 10.1007/s40618-019-01081-y. Epub 2019 Jul 1. PMID: 31264142.
58. Muller, A., Drexhage, H., & Berghout, A. (2001). Postpartum thyroiditis and autoimmune thyroiditis in women of childbearing age: recent insights and consequences for antenatal and postnatal care. Endocrine Reviews. Retrieved from http://hdl.handle.net/1765/9769
59. B12 NICE guidelines, maart 2024 https://www.nice.org.uk/guidance/ng239/chapter/recommendations
60. https://rarediseases.info.nih.gov/diseases/3024/hereditary-intrinsic-factor-deficiency
61. https://www.discovermagazine.com/the-human-brain-has-been-getting-smaller-since-the-stone-age-11139 Since starting agriculture
62. Lindenbaum, J., Healton, E. B., Savage, D. G., Brust, J. C. M., Garrett, T. J., Podell, E. R., . . . Allen, R. H. (1988). Neuropsychiatric Disorders Caused by Cobalamin Deficiency in the Absence of Anemia or Macrocytosis. New England Journal of Medicine, 318(26), 1720-1728. doi: doi:10.1056/NEJM198806303182604
63. https://abcd.amsterdamumc.nl/en/results/ More crying babies in mothers with low B12.
64. https://www.researchgate.net/publication/340020959_Maternal_vitamin_B12_deficiency_in_rats_alters_DNA_methylation_in_metabolically_important_genes_in_their_offspring
65. Vitamin B12 Deficiency: A Treatable Cause of Developmental Delay In Infancy https://onlinelibrary.wiley.com/doi/10.1111/jpc.12158
66. Isik et al, 2017 Epileptic Spasms and Partial Seizures Associated with Vitamin B12 Deficiency: Case Report and Literature Review DOI: 10.14744/epilepsi.2016.08760
67. https://www.theguardian.com/society/2025/jan/01/hospital-admissions-lack-of-vitamins-iron-nhs-
68. McNeil K, Chowdhury D, Penney L, Rashid M. Vitamin B12 deficiency with intrinsic factor antibodies in an infant with poor growth and developmental delay. Paediatr Child Health. 2014 Feb;19(2):84-6. doi: 10.1093/pch/19.2.84. PMID: 24596481; PMCID: PMC3941681.
69. Dror DK, Allen LH. Effect of vitamin B12 deficiency on neurodevelopment in infants: Current knowledge and possible mechanisms. Nutr Rev. 2008;66:250–5. doi: 10.1111/j.1753-4887.2008.00031.x.
70. Korenke GC, Hunneman DH, Eber S, Hanefeld F. Severe encephalopathy with epilepsy in an infant caused by subclinical maternal pernicious anemia: Case report and review of the literature. Eur J Pediatr. 2004;163:196–201. doi: 10.1007/s00431-004-1402-4.
71. Wagner CL, Hollis BW. The Implications of Vitamin D Status During Pregnancy on Mother and her Developing Child. Front Endocrinol (Lausanne). 2018 Aug 31;9:500. https://pmc.ncbi.nlm.nih.gov/articles/PMC6127214/
72. Hollis BW, Wagner CL, Howard CR, Ebeling M, Shary JR, Smith PG, Taylor SN, Morella K, Lawrence RA, Hulsey TC. Maternal Versus Infant Vitamin D Supplementation During Lactation: A Randomized Controlled Trial. Pediatrics. 2015 Oct;136(4):625-34. doi: 10.1542/peds.2015-1669. Erratum in: Pediatrics. 2019 Jul;144(1):e20191063. doi: 10.1542/peds.2019-1063. PMID: 26416936; PMCID: PMC4586731. https://pubmed.ncbi.nlm.nih.gov/26416936/
73. Bruce W Hollis, Carol L Wagner, Vitamin D requirements during lactation: high-dose maternal supplementation as therapy to prevent hypovitaminosis D for both the mother and the nursing infant23,The American Journal of Clinical Nutrition,Volume 80, Issue 6,2004,Pages 1752S-1758S,ISSN 0002-9165, https://doi.org/10.1093/ajcn/80.6.1752S.
74. Mulligan ML, Felton SK, Riek AE, Bernal-Mizrachi C. Implications of vitamin D deficiency in pregnancy and lactation. Am J Obstet Gynecol. 2010 May;202(5):429.e1-9. doi: 10.1016/j.ajog.2009.09.002. Epub 2009 Oct 20. PMID: 19846050; PMCID: PMC3540805.
75. https://myemail.constantcontact.com/Approximately-68--of-Pregnant-Black-Women-have-Vitamin-D-Levels-Below-20-ng-ml.html?soid=1102722411090&aid=gQRe_WqRaIM

 

 

 

 

 

Let me help you!

You can email on: mvanbroekhoven22@gmail.com

To plan a Teams consultation

 

I am not a medical doctor, but I've been able to help others as a nurse to find them and their family where to look further. At any time you worry about your health, always contact your family doctor or GP.