Folate 5-MTHF — Supplements

Bioactive methylated form of folate bypassing MTHFR enzyme for optimal methylation and DNA synthesis.

Overview

5-Methyltetrahydrofolate (5-MTHF) is the biologically active, methylated form of folate that directly participates in one-carbon metabolism without requiring conversion by MTHFR (methylenetetrahydrofolate reductase). This is clinically significant because up to 40% of the population carries MTHFR polymorphisms (C677T or A1298C) that reduce enzymatic conversion of folic acid to active 5-MTHF. Folate is essential for DNA synthesis, methylation reactions, homocysteine metabolism, and neural tube development. 5-MTHF supplementation effectively raises folate status regardless of MTHFR genotype.

Indications

  • Homocysteine reduction and methylation support
  • Neural tube defect prevention (preconception/prenatal)
  • MTHFR polymorphism management
  • DNA synthesis and cell division support
  • Mood and cognitive support (adjunctive to antidepressants)

Mechanism of Action

5-MTHF donates its methyl group to homocysteine via methionine synthase (B12-dependent), regenerating methionine

Dosing

CompoundDoseFrequencyNotes
5-MTHF (Methylfolate)1,000 mcgOnce dailyPreferred over folic acid for individuals with MTHFR polymorphisms

Evidence Grade

GRADE C

Safety & Contraindications

  • High-dose folate may mask vitamin B12 deficiency (megaloblastic anemia); always co-supplement B12
  • 5-MTHF does not interfere with methotrexate efficacy (unlike folic acid)
  • Generally well tolerated; rare reports of GI upset or insomnia
  • Excessive folate may theoretically promote growth of pre-existing neoplastic cells