VOL. I · 2026 · EVIDENCE-LED SUPPLEMENT RESEARCHUSA & GLOBAL EDITION
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ING-088Ingredient Research Profile

Vitamins

Vitamin B12 (Methylcobalamin)

Also known as: Methylcobalamin · Cyanocobalamin · Cobalamin

●●●Strong Evidence

The only vitamin exclusively found in animal foods. Deficiency causes irreversible nerve damage. Essential supplementation for vegans and those over 50.

Effective Dose

500–1000mcg / day

per clinical evidence

Evidence Level

Strong

Vitamins

Mechanism

Methylation co-factor, myelin synthesis, red blood cell maturation

primary action

Best For

Energy

Nerve health, Vegan diets, Deficiency correction

This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.

What Is Vitamin B12 (Methylcobalamin)?

Vitamin B12 is a cobalt-containing vitamin essential for DNA synthesis, myelin formation, and homocysteine methylation. It is found exclusively in animal-derived foods, making deficiency universal among vegans without supplementation. Absorption requires intrinsic factor — a glycoprotein secreted by gastric parietal cells that declines with age.

How It Works: The Science

B12 is a co-factor for methionine synthase (methylation cycle — converts homocysteine to methionine) and methylmalonyl-CoA mutase (odd-chain fatty acid and amino acid catabolism). Deficiency impairs myelin synthesis (neurological damage) and DNA methylation, causing megaloblastic anaemia and subacute combined degeneration of the spinal cord.

Primary Mechanism

Methylation co-factor, myelin synthesis, red blood cell maturation

Evidence-Based Benefits

Corrects B12 deficiency anaemia and fatigue

strong

Standard of care — deficiency correction universally effective

Prevents peripheral neuropathy in deficient individuals

strong

Neurological symptoms reverse with early treatment; irreversible if delayed

Reduces homocysteine (cardiovascular risk marker)

strong

B12 + folate + B6 combination reduces homocysteine by 25–30%

Dosage Guide

Effective Dose

500–1000mcg / day

500–1000mcg/day. Methylcobalamin is the bioactive form preferred over cyanocobalamin. High oral doses (1000mcg) compensate for impaired intrinsic factor via passive diffusion — effective even with absorption problems.

Safety Profile & Side Effects

Extremely safe — no established upper tolerable limit. Water-soluble, excess excreted in urine. No toxicity reported at any oral dose.

Who Should (and Shouldn't) Take It

Best for
EnergyNerve healthVegan dietsDeficiency correction
Who it's for

All vegans and vegetarians (mandatory), adults over 50 (declining intrinsic factor), those on metformin (depletes B12), and anyone with low energy of unknown cause.

Frequently Asked Questions

What is the recommended dose of Vitamin B12 (Methylcobalamin)?

500–1000mcg/day. Methylcobalamin is the bioactive form preferred over cyanocobalamin. High oral doses (1000mcg) compensate for impaired intrinsic factor via passive diffusion — effective even with absorption problems.

Is Vitamin B12 (Methylcobalamin) safe?

Extremely safe — no established upper tolerable limit. Water-soluble, excess excreted in urine. No toxicity reported at any oral dose.

How does Vitamin B12 (Methylcobalamin) work?

B12 is a co-factor for methionine synthase (methylation cycle — converts homocysteine to methionine) and methylmalonyl-CoA mutase (odd-chain fatty acid and amino acid catabolism). Deficiency impairs myelin synthesis (neurological damage) and DNA methylation, causing megaloblastic anaemia and subacute combined degeneration of the spinal cord.

Who should take Vitamin B12 (Methylcobalamin)?

All vegans and vegetarians (mandatory), adults over 50 (declining intrinsic factor), those on metformin (depletes B12), and anyone with low energy of unknown cause.

Related Ingredients

Folate (Methylfolate / Vitamin B9)Vitamin B6 (Pyridoxal-5-Phosphate)Iron (Ferrous Bisglycinate)N-Acetyl Cysteine (NAC)

Medical Disclaimer

Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →