Vitamins & absorptionThe B-vitamin gene

MTHFR

Methylenetetrahydrofolate reductase gene

MTHFR in one lineMTHFR is the gene that helps your body activate folate and vitamin B12, and a common variant makes that process less efficient.

What it does

The MTHFR gene produces an enzyme central to processing folate and recycling homocysteine, steps that matter for energy, nerve function, and, in pregnancy, healthy fetal development.

The variants that matter

Common variants reduce the enzyme's efficiency, so the body activates folate and B12 less effectively. Many people carry one or two copies and never notice, while others feel it as low energy or raised homocysteine.

If you carry the notable variant

It can mean standard supplement forms are less useful for you, and that the active forms of folate and B12 are absorbed better. It is worth a conversation with a doctor, especially before and during pregnancy.

Why it matters in India

MTHFR variants are common in Indian populations, and combined with widespread B12 deficiency in largely vegetarian diets, this gene is one of the more practically relevant entries in this encyclopedia for the region.

The honest caveat. MTHFR is heavily over-hyped online, with many unproven claims attached to it. The genuine, evidence-based implications are real but narrow. Treat dramatic internet claims about it with caution.

Browse all gene entries