Vitamin B12
Essential for red blood cell formation, neurological function, and DNA synthesis — vegans are at high risk of deficiency.
Dosage
Recommended
250–1000 mcg daily
Upper limit
No established upper limit
Key Benefits
- 01Prevents megaloblastic anaemia
- 02Supports nerve myelin sheath integrity
- 03Improves energy metabolism
- 04Required for DNA synthesis
- 05Reduces homocysteine
Available Forms
Safety Notes
- —Metformin (reduces absorption)
- —PPIs (reduce absorption)
- —H2 blockers
This reference is for informational purposes only. Consult a qualified healthcare provider before starting any supplement.
Related content
Guide
Vitamin B12 Cognition Meta-analysis: What the Evidence Says
Guide
Vitamin B12: Methylcobalamin vs Cyanocobalamin and Who Needs to Supplement
Guide
Vitamin B12 Deficiency: What the Evidence Says
Compare
Vitamin B12 Methylcobalamin vs Vitamin B12 Cyanocobalamin
Answer
What does the evidence say about Vitamin B12 Deficiency?
Answer
Is Vitamin B12 Deficiency safe?
Answer
Does Vitamin B12 Deficiency work?
Data
Vitamin B12 Deficiency Evidence Table
Data
Vitamin B12 Cognition Meta-Analysis Evidence Table