Evidence-Based Nutrient Recommendations

B12 Deficiency Cases in Vegan Infants and Toddlers

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Unless otherwise noted, all infants were healthy until about 6-12 months after which they failed to thrive and showed developmental regression. All became lethargic and lost their ability to use their muscles adequately. Some could not sense properly and most had macrocytic anemia. “Additional Symptoms” only lists symptoms in addition to those just described.

Normal serum B12 (sB12) for newborns: 160-1300 pg/ml

2014, Chile, 12 months

A 12-month old infant, daughter of a longtime vegetarian woman, who presented neurological and hematological compromise due to vitamin B12 deficiency, is discussed. After a short period of parenteral administration of cyanocobalamin and enteral nutrition, the patient evolved with clinical and laboratory improvement, although she still had residual development delay.

Bravo J P, Ibarra C J, Paredes M M. [Hematological and neurological compromise due to vitamin B12 deficit in infant of a vegetarian mother: case report]. Rev Chil Pediatr. 2014 Jun;85(3):337-43.

2014, Turkey, 12 months

Breastfed infant of vegetarian mother was healthy until six months at which point growth and activity slowed. He was diagnosed with B12 deficiency and treated until age 18 months during which he made a full recovery.

Kocaoglu C, Akin F, Caksen H, Böke SB, Arslan S, Aygün S. Cerebral atrophy in a vitamin B12-deficient infant of a vegetarian mother. J Health Popul Nutr. 2014 Jun;32(2):367-71.

2012, Italy, 5 months

serum B12: 57 pg/ml

Exclusively breastfed by the vegan mother until admission. Mother had taken a multivitamin with 2.5 µg of B12 during the 2nd and 3rd trimester, but ceased after the baby was born. Infant had iron deficiency as well as highly elevated uMMA. Seven months of treatment resulted in drastic improvement but not full recovery.

Guez S, Chiarelli G, Menni F, Salera S, Principi N, Esposito S. Severe vitamin B12 deficiency in an exclusively breastfed 5-month-old Italian infant born to a mother receiving multivitamin supplementation during pregnancy. BMC Pediatr. 2012 Jun 24;12(1):85.

2009, Israel, 7 months

serum B12: deficient

Exclusively breastfed by strict vegetarian until admission.By the age of 1 year, she demonstrated normal social interaction, but delayed milestone achievements and hypotonia with normal tendon reflexes.

Abu-Kishk I, Rachmiel M, Hoffmann C, Lahat E, Eshel G. Infantile encephalopathy due to vitamin deficiency in industrial countries. Childs Nerv Syst. 2009 Jul 8. [Epub ahead of print]

2008, France, 6 months

serum B12: 10 pM
Exclusively breastfed by strict vegetarian until admission.At age of
2 years, his neurological development was normal.

Chalouhi C, Faesch S, Anthoine-Milhomme MC, Fulla Y, Dulac O, Cheron G. Neurological consequences of vitamin B12 deficiency and its treatment. Pediatr Emerg Care. 2008 Aug;24(8):538-41.

2007, France, Two Infants, 11 and 13 months

serum B12: deficient
Infants were breastfed by strict vegetarians.
Results/Notes: Outcome not clear from abstract (article is in French).

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. Epub 2007 Apr 6. French.

2005, France, Girl, 9.5 months

serum B12: deficient
Infant was exclusively breastfed by a vegan mother who was also B12 deficient.
Results/Notes: No outcome details given in abstract (article is in French).

Wagnon J, Cagnard B, Bridoux-Henno L, Tourtelier Y, Grall JY, Dabadie A. [Breastfeeding and vegan diet] J Gynecol Obstet Biol Reprod (Paris). 2005 Oct;34(6):610-2. French.

2005, Italy, Boy, 10 months

serum B12: 30 pg/ml
uMMA: 851 (normal is < 2)
Infant was breastfed by a mother who had been vegan for ten years.
Additional symptoms: Labored breathing, brain atrophy.
Treatment: 1000 mcg/day B12, 7.5 mg/day folate, 50 mg/day iron, and put on a mechanical ventilator.
Results/Notes: Marked improvement 11 days after admission. At age 4, important improvements achieved but still having psychomotor delay and involuntary movements when agitated.

Codazzi D, Sala F, Parini R, Langer M. Coma and respiratory failure in a child with severe vitamin B(12) deficiency. Pediatr Crit Care Med. 2005 Jul;6(4):483-5.

2003, USA (Georgia), 2 Infants

When this story broke in 2003, there were some counter-articles making their way around the web, one saying that these infants were suffering from a genetic B12 metabolism defect rather than from a lack of intake. For that reason, some points are clarified on these two infants.

Case 1

Mother: Vegan with supplements. Took supplements, but B12 content unknown.
Infant: Breast-fed for first 8 months (possibly with other foods). Apparently vegan from 8–15 months, with no B12 intake. At 15 months showed failure to thrive, developmental delay. Serum B12: 100 pg/ml (normal: 210-911). Urine Methyl Malonic Acid (MMA): marked elevation.
Treatment: First 3 days: Extra food via tube; 2,000 ug and 3,000 ug injections of B12. At some later point, she was prescribed daily B12 sublingual supplements. At 32 months: Was making progress but had some developmental delays.

This infant was apparently vegan from 8–15 months, possibly with no B12 intake at all (the report is not clear as to whether the baby received breast milk during this period). MMA is the most precise marker of B12 function, and this infant’s markedly elevated MMA shows she was suffering either from a lack of intake, lack of absorption, or inability to utilize B12. She received two B12 injections at 15 months, followed by daily B12 supplements.

Improvement from a B12 injection can generally last 3 to 6 months. This infant was apparently still making progress 17 months after her B12 injections, indicating that she did not have a B12 utilization problem. While it is possible that this infant doesn’t absorb B12 efficiently and must rely on higher-than-normal doses, her problems were most likely due to a low or absent B12 intake between her 8th and 15th month.

Case 2

Mother: Plant-based with small amounts of animal products; “intermittent” B12 supplements of 250 mcg
Infant: Exclusively breastfed for 9 months. At 9 months, growth and development appeared delayed.
Treatment: Breast-milk supplemented with fruit and dried cereals.
At 11 months: Poor speech and growth development.
Treatment: Soy and dairy formula tried, but not tolerated; thus started on Multigrain Milk (B12 content, if any, not given), chicken, and an unknown vitamin supplement.
At 30 months: Serum B12: 100 pg/ml (normal: 210-911). Urine MMA: Moderate elevation. Plasma homocysteine: 12.4 umol/l (normal 3.3-8.3). MCV (mean corpuscular volume): 103.2 fl (normal: 77 – 86). Normal serum folate.
Treatment: 1,000 mcg B12 injection. 2 weeks later: 1,000 mcg sublingual B12 daily. Speech, language, and occupational therapies.
At 36 months: Slight speech and fine motor skill delays, but normal gross motor skills.

This infant had 2 indicators of poor B12 activity: somewhat elevated MMA, and a high homocysteine and MCV with normal folate. Once vitamin B12 was injected, his development improved. His progress was measured again only 6 months after the injection, so it is possible that he was suffering from an inability to absorb or utilize B12.

Since there is no indication that he ever received an adequate amount of B12 on a regular basis, lack of B12 in the diet is the most likely explanation.

From the Centers for Disease Control and Prevention. Neurologic impairment in children associated with maternal dietary deficiency of cobalamin–Georgia, 2001. JAMA. 2003 Feb 26;289(8):979-80.

2001, Czech Republic, Girl, 13 months

Serum B12: low Additional Symptoms: Brain atrophy. Treatment: B12 supplements. Results/Notes: English abstract says she was fed only “vegetables” after 9 months of age, but Marek Vorsilka informs me that the original paper in Czech says she was fed a range of plant foods including fruit, potatoes, millet, corn gruel, lentils, beans, rice, carrot, soya milk, sunflower, flaxseed and sesame seeds. Elevated MMA. Condition improved after treatment.

Smolka V, Bekarek V, Hlidkova E, Bucil J, Mayerova D, Skopkova Z, Adam T, Hruba E, Kozich V, Buriankova L, Saligova J, Buncova M, Zeman J. [Metabolic complications and neurologic manifestations of vitamin B12 deficiency in children of vegetarian mothers] Cas Lek Cesk. 2001 Nov 22;140(23):732-5. In Czech. (Abstract)

2001, Czech Republic, Boy, 8 months

Serum B12: low Treatment: B12 supplements. Results/Notes: Fed breast milk and fruit juice only after 6 m. Elevated MMA & HCY. Mother’s B12 was low. Improved after treatment but still had problems including language delay.

Smolka V, Bekarek V, Hlidkova E, Bucil J, Mayerova D, Skopkova Z, Adam T, Hruba E, Kozich V, Buriankova L, Saligova J, Buncova M, Zeman J. [Metabolic complications and neurologic manifestations of vitamin B12 deficiency in children of vegetarian mothers] Cas Lek Cesk. 2001 Nov 22;140(23):732-5. In Czech. (Abstract)

2001, Hungary, 9 months

Serum B12: Not reported Additional Symptoms: Repetitive vomiting, trouble swallowing, tremors. Treatment: B12 injections. Results/Notes: Improved dramatically in days. Blood was normal after 6 weeks.

Fogarasi A, Neuwirth M, Bekesi A, Bocskai E. [No title given.] Orv Hetil. 2001 Nov 18;142(46):2581-5. Hungarian. (Abstract)

2000, Italy, Boy, 22 months

Serum B12: 75 pg/ml Additional Symptoms: pH 6.95 (severe acidosis) Treatment: Intravenous hydroxocobalamin 1,000 µg/d, biotin, carnitine, and high-caloric, low protein formula. Results/Notes: Mother’s B12 level was 162 pg/ml. Made complete recovery in 3 months. Lack of elevated HCY led researchers to determine the boy had a mild case of genetic methylmalonyl-CoA mutase deficiency which was exacerbated by a low B12 intake.

Ciani F, Poggi GM, Pasquini E, Donati MA, Zammarchi E. Prolonged exclusive breastfeeding from vegan mother causing an acute onset of isolated methylmalonic aciduria due to a mild mutase deficiency. Clin Nutr. 2000 Apr;19(2):137-9.

1999, Australia, 2 Newborns

In screening 137,120 newborns for inborn error of metabolism, they found 2 B12 deficient babies of vegan mothers. No further information was given. “B12-deficient” was not defined.

Wiley V, Carpenter K, Wilcken B. Newborn screening with tandem mass spectrometry: 12 months’ experience in NSW Australia. Acta Paediatr. Suppl 1999 Dec;88(432):48-51

1999, France, Boy, 10 months

Serum B12: Not reported Additional Symptoms: Regurgitation, edema. Treatment: 300 µg/day of B12 Results/Notes: Suffered muscle tremors during 1st 4 days of treatment. Normal after 2 months. Mother had a sB12 of 109 pg/ml with normal intrinsic factor function.

Renault F, Verstichel P, Ploussard JP, Costil J. Neuropathy in two cobalamin-deficient breast-fed infants of vegetarian mothers. Muscle Nerve. 1999 Feb;22(2):252-4.

1999, France, Boy, 12 months

Serum B12: Not Reported Additional Symptoms: Low level of red and white blood cells, and platelets. Treatment: 1,000 µg/day B12 Results/Notes: Had increased homocysteine and MMA in urine. Suffered muscle tremors during 1st 3 days of treatment. Normal after 3 weeks.

Renault F, Verstichel P, Ploussard JP, Costil J. Neuropathy in two cobalamin-deficient breast-fed infants of vegetarian mothers. Muscle Nerve. 1999 Feb;22(2):252-4.

1999, Australia, Boy, 18 months

Serum B12: 202 pg/ml Additional Symptoms: Stopped developing at 1 year. Treatment: 500 µg B12/day injections. Results/Notes: Mother’s diet showed a B12 intake of .3 µg/day and sB12 of 202. She also had B12 malabsorption thought to be due to a temporary small intestine problem caused by B12 deficiency. After treatment, child’s twitching developed into episodes more like seizures as his neurological status gradually improved.

Grattan-Smith PJ, Wilcken B, Procopis PG, Wise GA. The neurological syndrome of infantile cobalamin deficiency: developmental regression and involuntary movements. Mov Disord. 1997 Jan;12(1):39-46.

1999, Australia, Girl, 12 months

Serum B12: 50 pg/ml Additional Symptoms: Irritable, lethargic, and constipated. Treatment: 1500 µg B12 injections. Results/Notes: After 2nd injection, she developed tremors which eventually went away and she returned to normal.

Grattan-Smith PJ, Wilcken B, Procopis PG, Wise GA. The neurological syndrome of infantile cobalamin deficiency: developmental regression and involuntary movements. Mov Disord. 1997 Jan;12(1):39-46.

1999, Australia, Boy, 10 months

Serum B12: 47 pg/ml Additional Symptoms: Intermittent tremors that had started at 4 months. Treatment: 1000 µg B12/day injections for 6 d. Results/Notes: Developed tremors (after treatment) which lasted for 6 weeks. By 23 months, motor skills were normal, but intellectual development appeared to be slow for his age.

Grattan-Smith PJ, Wilcken B, Procopis PG, Wise GA. The neurological syndrome of infantile cobalamin deficiency: developmental regression and involuntary movements. Mov Disord. 1997 Jan;12(1):39-46.

1997, Germany, boy, 14 months

serum B12: Not reported Additional Symptoms: Severe nerve problems. Comatose at hospital admission. Severe brain atrophy. Treatment: One 250 µg B12 injection. 25 µg oral B12/day plus supplemented soy formula. Results/Notes: uMMA was initially very high. Mother had been vegan for 6 years, and vegetarian for 8 years prior to that. She ate a high proportion of raw foods. The infant had been exclusively breastfed for 9 months and then ate small amounts of fruit. Regained consciousness in hours. By day 3 was able to walk, eat, drink, and was discharged. Parents agreed to give soy formula and oral B12. Cranial MRI 10 weeks later showed all structural brain abnormalities had disappeared, but he continued to show nerve damage. At 2 years, still showed psychomotor retardation, was agitated and had poor concentration. Could not speak any words. 3-year-old sister had B12 level of 139 pg/ml. Mother had B12 level of 149 pg/ml which became normal after oral supplementation.

von Schenck U, Bender-Gotze C, Koletzko B. Persistence of neurological damage induced by dietary vitamin B-12 deficiency in infancy. Arch Dis Child. 1997 Aug;77(2):137-9.

1997, Switzerland, Girl, 14 months

Serum B12: 124 pg/ml Additional Symptoms: Severe brain atrophy. Treatment: Multivitamin, iron, folic acid, trace elements, *1 ng B12 every other day. Results/Notes: Responded well and at 20 months could sit alone, crawl, walk with help, and speak simple words. *The “1 ng” was probably a typographical error and was actually “1 mg” (1,000 µg).

Lovblad K, Ramelli G, Remonda L, Nirkko AC, Ozdoba C, Schroth G. Retardation of myelination due to dietary vitamin B12 deficiency: cranial MRI findings. Pediatr Radiol. 1997 Feb;27(2):155-8.

1996, Greece, 3 Boys and 1 Girl, 2 – 5 weeks

Serum B12: Very low. Additional Symptoms: Low hemoglobin, no megaloblastic anemia. Vomiting in 3 out of 4. Elevated urinary MMA (exact number not reported). Treatment: “Appropriate treatment.” Results/Notes: Mothers also had elevated urinary MMA. All children doing very well after 4 – 5.5 years.

Drogari E, Liakopoulou-Tsitsipi T, Xypolyta-Zachariadi A, Papadellis F, Kattamis C. Transient methylmalonic aciduria in four breastfed neonates of strict vegetarian mothers in Greece. Journal of inherited metabolic disease. 1996 19S:A84. (Only an abstract.)

1993, France, 15 months

Serum B12: Very low Additional Symptoms: Severe megaloblastic anemia. No growth. Lack of muscle tone and psychomotor development. Treatment: Injections and possibly a blood transfusion. Results/Notes: Very low levels of B12 in the milk of the mother who had been vegan for 10 years. At 4 years old, patient’s growth and psychomotor development were normal.

Monfort-Gouraud M, Bongiorno A, Le Gall MA, Badoual J. Severe megaloblastic anemia in child breastfed by a vegetarian mother. Ann Pediatr (Paris). 1993 Jan;40(1):28-31. [Article in French.] (Abstract)

1991, Switzerland, Girl, 9 months

Serum B12: 28 pg/ml Additional Symptoms: Optic nerve atrophy. Treatment: 1000 µg injection for 4 days. 1000 µg orally on the 5th day. Results/Notes: Urinary MMA and plasma homocysteine were initially very high. All muscle problems vanished after 10 days. The girl was discharged and parents were given an oral vitamin B complex including B12. Parents agreed to add eggs and dairy to her diet. By 15th month, her physical measurements and lab values were normal.

Kuhne T, Bubl R, Baumgartner R. Maternal vegan diet causing a serious infantile neurological disorder due to vitamin B12 deficiency. Eur J Pediatr. 1991 Jan;150(3):205-8.

1992, Australia, 3 Infants

Results/Notes: Reviewed the cases of B12 deficiency seen during the previous 10 y at Prince of Wales Children’s Hospital to obtain long-term follow-up. 3 of the 6 patients were infants of vegetarian mothers. 1 had borderline intellectual development at age 5.

Graham SM, Arvela OM, Wise GA. Long-term neurologic consequences of nutritional vitamin B12 deficiency in infants. J Pediatr. 1992 Nov;121(5 Pt 1):710-4.

1992, Canada, Girl, 2.5 months

Serum B12: 104 pg/ml Additional Symptoms: Had no symptoms. Treatment: Oral B12. Results/Notes: Urinary MMA started at 537 µmol/mmol Cr, but dropped to 10.9 after 2 weeks. Mother’s B12 level was 81 pg/ml.

Michaud JL, Lemieux B, Ogier H, Lambert MA. Nutritional vitamin B12 deficiency: two cases detected by routine newborn urinary screening. Eur J Pediatr. 1992 Mar;151(3):218-20.

1990, Israel, 14 months

Serum B12: Not reported. Additional Symptoms: Severe nerve damage. Treatment: B12 therapy. Results/Notes: Partially corrected.

Bar-Sella P, Rakover Y, Ratner D. Vitamin B12 and folate levels in long-term vegans. Isr J Med Sci. 1990;26:309-312.

1989, France, Girl, 6 months

Serum B12: 45 pg/ml Additional Symptoms: Hemoglobin 1.9 g/dl. Treatment: B12 injection(s). Results/Notes: Parents’ B12 levels: 110 and 105 pg/ml. B12 in mother’s milk: 12 pg/ml. Treatment was successful.

Cheron G, Girot R, Zittoun J, Mouy R, Schmitz J, Rey J. Severe megaloblastic anemia in 6-month-old girl breast-fed by a vegetarian mother. Arch Fr Pediatr. 1989 Mar;46(3):205-7. [Article in French.] (Abstract)

1987, Germany, Boy, 18 months

Serum B12: 63 pg/ml Additional Symptoms: Progressive nerve disorder since 6 months of age. Treatment: 1000 µg B12/day. Results/Notes: Serum MMA and urinary MMA were not elevated. At 5 weeks, anemia was gone and nerve problems dramatically improved. At 26 months, was functioning at a 12-month-old level with exaggerated reflexes. Continued to make psychomotor progress. Authors thought the normal MMA levels were possibly due to the small amounts of animal products prior to hospital admission.

Stollhoff K, Schulte FJ. Vitamin B12 and brain development. Eur J Pediatr. 1987 Mar;146(2):201-5.

1986, Switzerland, Boy, 11 months

Serum B12: Not reported. Treatment: Admitted to hospital and given three 500 µg B12 injections in 6 days. Results/Notes: Full recovery. Discharged with an oral vitamin supplement containing 6 µg B12/day and oral iron. Mother did not follow the advice to give iron. Child was readmitted 2 months later showing iron deficiency. He was put on an iron supplement and blood values returned to normal in 1 month. No relapse of B12 deficiency was noted after oral supplementation. The infant was a twin. The other twin was not reported to have problems.

Gambon RC, Lentze MJ, Rossi E. Megaloblastic anaemia in one of monozygous twins breast-fed by their vegetarian mother. Eur J Pediatr. 1986 Dec;145(6):570-1.

1986, USA, Boy

Serum B12: Not reported. Additional Symptoms: Swelling of hands, feet, and abdomen. Treatment: Blood transfusion, 1000 µg B12 injections for 5 days. Child & Mother: 1 month of 50 µg B12/day 4 months of multivitamins. Results/Notes: Improved in 48 hours. Discharged on 4th day. Was doing much better after 6 months. The parents had been vegan for 6 years. 2 weeks prior to admission, a naturopath suggested they take him to a hospital. The parents refused, but the mother agreed to begin taking a multivitamin.

Sklar R. Nutritional vitamin B12 deficiency in a breast-fed infant of a vegan-diet mother. Clin Pediatr (Phila). 1986 Apr;25(4):219-21.


1985, Norway, Girl, 2 years

Serum B12: 54 pg/ml Treatment: B12 injections, vitamin D, calcium, and iron. Results/Notes: Also suffered from rickets. The girl ate small amounts of milk, eggs, and cod liver oil. Her symptoms of rickets and B12 deficiency resolved after 2 weeks. Mother was pregnant and her serum B12 was 149 pg/ml. She was given B12 injections and a multivitamin and she and the baby have both done well.

Hellebostad M, Markestad T, Seeger Halvorsen K. Vitamin D deficiency rickets and vitamin B12 deficiency in vegetarian children. Acta Paediatr Scand. 1985 Mar;74(2):191-5.

1983, Dominica, Boy, 12 months

Serum B12: Not reported. Additional Symptoms: Vomiting. Treatment: Oral B12 for 42 days. Results/Notes: Full recovery.

Close, GC. Rastafarianism and the vegans syndrome. British Medical Journal. 1983;286(Feb 5):473.

1981, USA, Boy, 6 months

Serum B12: Not reported Additional Symptoms: Heart failure. Treatment: B12 injections. Results/Notes: Mother’s B12 was 278 pg/ml. By day 28, all blood values were normal. Infant was then given 50 µg B12 twice per week.

Davis JR, Goldenring J, Lubin B. Nutritional vitamin B12 deficiency in infants. Am J Dis Child. 1981(Jun);135:566-7.

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