Vitamin B12 Methylcobalamin — Supplements
Bioactive coenzyme form of vitamin B12 for methylation, neurological function, and red blood cell formation.
Overview
Methylcobalamin is one of two biologically active coenzyme forms of vitamin B12 (the other being adenosylcobalamin). It serves as a cofactor for methionine synthase, which converts homocysteine to methionine and is essential for myelin synthesis, DNA production, and red blood cell formation. Deficiency affects 6-20% of adults over 60 due to reduced intrinsic factor and gastric acid production. Methylcobalamin is preferred over cyanocobalamin for supplementation as it bypasses the need for metabolic conversion and directly supports methylation.
Indications
- B12 deficiency prevention and treatment
- Methylation support
- Neurological function and nerve health
- Megaloblastic anemia prevention
- Energy metabolism support
Mechanism of Action
Methylcobalamin transfers its methyl group to homocysteine via methionine synthase, regenerating methionine
Dosing
| Compound | Dose | Frequency | Notes |
|---|---|---|---|
| Vitamin B12 (Methylcobalamin) | 1,000 mcg | Once daily | Sublingual may bypass absorption issues in pernicious anemia |
Safety & Contraindications
- Water-soluble with no established upper limit; excess excreted in urine
- Very safe profile; no significant adverse effects at supplemental doses
- High-dose folate can mask B12 deficiency symptoms; always co-supplement
- Individuals on metformin, PPIs, or H2 blockers are at higher risk of deficiency