Vitamin B12
VitaminsKey Benefits
How It Works
Cobalamin serves as a cofactor for two critical enzymes: methionine synthase (essential for DNA methylation) and methylmalonyl-CoA mutase (involved in fatty acid and amino acid metabolism). Deficiency causes megaloblastic anaemia and neurological damage.
Dosage & Timing
Recommended Dosage
500-2,000 mcg daily (higher for deficiency)
Best Time to Take
Morning on empty stomach or with breakfast
Recommended Form
Methylcobalamin or adenosylcobalamin preferred
Side Effects
Very low toxicity even at high doses. Excess is excreted in urine. Rare allergic reactions reported.
Drug Interactions
Metformin, PPIs, and H2 blockers reduce B12 absorption. Colchicine and chloramphenicol may interfere.
What Does The Research Say?
Critical for vegans and older adults. Deficiency prevalence is 6-20% in over-60s. Sublingual and intramuscular routes bypass absorption issues. Research supports supplementation for deficiency-related cognitive decline.
Where to Buy
Buy Vitamin B12 on Amazon
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Try Huel →This information is for educational purposes only and does not constitute medical advice. Researched by the editorial team at NexoraOS, supplement user since 2018. Always consult a qualified healthcare professional before starting any supplement. Individual results may vary. Amazon links are affiliate links.