Methylfolate is the biologically active form of folate (vitamin B9) — the form your body actually uses. This matters because approximately 40% of the population has at least one copy of the MTHFR C677T polymorphism, reducing their ability to convert folic acid to methylfolate by 30-70%. Our research shows methylfolate supplementation bypasses this genetic bottleneck entirely. L-methylfolate (Deplin®) is also FDA-approved as a medical food for depression (15mg/day as SSRI adjunct), making it one of the very few supplements that has crossed into prescription territory. For pregnancy, adequate folate prevents 70% of neural tube defects — and methylfolate ensures those with MTHFR variants are protected.
Methylfolate (5-MTHF) is the final active form of folate that donates methyl groups in one-carbon metabolism. Its primary function: (1) remethylating homocysteine to methionine (via methionine synthase + B12), reducing cardiovascular-toxic homocysteine; (2) methionine → S-adenosylmethionine (SAMe) → methyl donor for DNA methylation, neurotransmitter synthesis (serotonin, dopamine, norepinephrine), and 200+ methylation reactions; (3) thymidylate synthesis for DNA replication (critical in pregnancy). The MTHFR enzyme converts folic acid → dihydrofolate → tetrahydrofolate → 5-MTHF. Variants (C677T, A1298C) reduce this enzyme's efficiency, creating a bottleneck that supplemental 5-MTHF bypasses entirely.
Based on independent third-party laboratory analysis
Category pass rate: ~75%. Dose accuracy and dissolution are the main issues.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.