Vitamins & Minerals

Vitamin B12 Deficiency

6 min readKilotaki Nutrition Editor
Vitamin B12 Deficiency

B12 only in animal products. Vegans, 50+ adults, gastric surgery patients, autoimmune gastritis sufferers at risk. Deficiency causes irreversible nerve damage if prolonged — early diagnosis critical.

Symptoms

Extreme fatigue, weakness, sore tongue (glossitis), tingling (hands/feet), balance issues, memory problems, depression, dementia-like symptoms (in elderly).

Test and Treatment

Serum B12 + methylmalonic acid + homocysteine. Low B12 (<300 pg/mL) requires supplementation. Treatment: oral 1000 mcg/day or IM injection. Vegans MUST take 25 mcg daily or 2000 mcg weekly.

  • Animal sources: chicken, fish, egg, dairy
  • Fortified plant milk, nutritional yeast
  • Algae B12 'analogs' inactive — no benefit

Frequently Asked Questions

Is deficiency reversible?

Early — yes. Long-term nerve damage may be permanent. Vegans must supplement.

Scientific References

  1. Stabler SP (2013) Vitamin B12 deficiency. NEJM.

This content is for general information only and does not replace medical advice. Consult your physician or a registered dietitian for personalized guidance.

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