Neural-tube-defect prevention uses 400 µg/day folic acid before conception and early pregnancy; high risk is clinician-managed
Reviewed · Published
Folate
Required for one-carbon metabolism, DNA synthesis, and red-blood-cell formation.
Established functions
- Required for one-carbon metabolism, DNA synthesis, and red-blood-cell formation.
Dietary sources
- spinach
- edamame
- lentils
Claims and evidence
Claims that Folate alone prevents or treats disease, or invariably improves health without deficiency, are unsupported.
Japanese reference amounts
- Japanese adults (age and sex as specified): Adults 240 µg DFE/day; those planning pregnancy add 400 µg/day folic acid
Amounts studied
- Neural-tube-defect prevention uses 400 µg/day folic acid before conception and early pregnancy; high risk is clinician-managed
Tolerable upper limits
- Adults: 900–1,000 µg/day of synthetic folic acid
Forms and bioavailability
Supplement forms: folic acid, 5-MTHF
- Folic acid taken fasting is more bioavailable than food folate; DFE conversion matters.
Safety and interactions
Adverse effects
- high doses may mask the hematologic signs of B12 deficiency
Medicine and nutrient interactions
- methotrexate, antiseizure medicines, sulfasalazine
Contraindications and cautions
- Do not self-treat anemia with high doses before excluding B12 deficiency.
Practical selection
- Compare Folate amount per serving, form, allergens, and batch testing; prefer a single-ingredient product suited to the intended use.
Sources and review
- Dietary Reference Intakes for Japanese (2025)Ministry of Health, Labour and Welfare (Japan)
- NIH ODS vitamin fact sheetsNIH Office of Dietary Supplements
Daiki Minaki (editorial and evidence review) ·
Frequently asked questions
How is Folate different from its broader supplement category?
Required for one-carbon metabolism, DNA synthesis, and red-blood-cell formation. Compare its named form and amount rather than assuming every category product supplies it.
View detailsWhat safety detail matters specifically for Folate?
methotrexate, antiseizure medicines, sulfasalazine Do not self-treat anemia with high doses before excluding B12 deficiency.
View details