Overview
Bioactive folate that bypasses the MTHFR enzyme — preferred in MTHFR variants and pregnancy.
- Whole-food sources (animal products for fat-soluble and B-complex vitamins; produce for water-soluble vitamins)
- Fortified foods (cereals, dairy, plant milks, nutritional yeast)
- Multivitamins or stand-alone supplements in synthetic or food-derived form
- Capsule or softgel
- Sublingual tablet or liquid
- Methylated active form for sensitive individuals
- Multivitamin matrix
Forms & variants of Folate (Vitamin B9)
Different chemical forms of Folate (Vitamin B9) behave differently. Browse each form's mechanism, bioavailability, and best-use context.
Mechanism of action
Skips dihydrofolate reductase and MTHFR — directly enters the methylation cycle as 5-MTHF.
- · Methylation cycle
- · Homocysteine remethylation
- · Monoamine synthesis (BH4)
Effects on the body
Organ system effects
Methylfolate (L-5-MTHF) modulates monoaminergic and GABAergic tone relevant to mood and anxiety regulation.
Methylfolate (L-5-MTHF) has documented effects on female reproductive endocrinology and cycle regulation.
Evidence-based benefits
Augments SSRI response in depression
Moderate evidencePrevents NTDs in pregnancy
Strong evidencePotential side effects
- · Anxiety/insomnia in overmethylators
Drug interactions
Supplement interactions
- Methylcobalamin (B12)Methyl trap prevention.
No specific avoidances listed.
Dosing & bioavailability
Where to buy
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Third-party testedIndependently verified Methylfolate (L-5-MTHF) — look for USP, NSF, or Informed Sport seals on the label for purity and dose accuracy.Methylfolate (L-5-MTHF) third party tested NSF
CapsulesPre-measured Methylfolate (L-5-MTHF) capsules — easiest for travel and consistent daily dosing without scoops or scales.Methylfolate (L-5-MTHF) capsules
PowderBulk unflavored Methylfolate (L-5-MTHF) powder — best cost-per-gram and flexible dosing for stacking or mixing into drinks.Methylfolate (L-5-MTHF) powder unflavored
Best sellersMost-purchased Methylfolate (L-5-MTHF) products on Amazon — a quick way to see what's reviewed widely before you commit.Methylfolate (L-5-MTHF) best sellerScientific evidence9Show studiesHide studies
L-methylfolate as adjunct in SSRI-resistant depression
Papakostas GI, et al.
60-day RCT of L-methylfolate in MDD.
Significant improvement in HAM-D scores vs placebo.
PubMed: Methylfolate (L-5-MTHF) — Augments SSRI response in depression
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PubMed: Methylfolate (L-5-MTHF) — Prevents NTDs in pregnancy
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PubMed: Methylfolate (L-5-MTHF) — randomized controlled trial
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PubMed: Methylfolate (L-5-MTHF) — pharmacokinetics
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PubMed: Methylfolate (L-5-MTHF) — safety adverse events
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PubMed: Methylfolate (L-5-MTHF) — dose response
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Google Scholar: Methylfolate (L-5-MTHF) — clinical evidence
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