Folate
Supplement
vitamin
women's healthheart & metabolic
Not medical advice. Check with your doctor or pharmacist before you start, stop or change the timing of anything you take.
How to use
What it’s for
DNA synthesis · 400 mcg/day folic acid if pregnancy possible
When to take
With or without food
Take with
With adequate B12 · high folate can mask a B12 deficiency
Pros & cons
Pros
- RDA 400 mcg dfe a day; 600 mcg dfe in pregnancy
- Folic acid around conception: fewer neural tube defects
- 5-mthf absorbs as well as or better than folic acid
Cons
- UL 1,000 mcg/day folic acid · HSA cap 0.9 mg/day
- Lowers homocysteine but not heart attack risk in trials
- High intakes can mask a B12 deficiency
Sources
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Table 1 RDAs; Groups at Risk — Women of childbearing age · read 2026-08-27
what it says
“19+ years 400 mcg DFE 400 mcg DFE 600 mcg DFE 500 mcg DFE … Women of childbearing age should obtain 400 mcg/day folic acid from dietary supplements and/or fortified foods in addition to the folate provided by a varied diet”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Introduction; Folate and Health — Neural tube defects · read 2026-08-27
what it says
“Folate functions as a coenzyme … in single-carbon transfers in the synthesis of nucleic acids (DNA and RNA) and metabolism of amino acids … clinical trial evidence shows that adequate periconceptional folic acid consumption by women prevents a substantial proportion of NTDs”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Sources of Folate — Dietary supplements · read 2026-08-27
what it says
“About 85% of supplemental folic acid, when taken with food, is bioavailable … When consumed without food, nearly 100% … is bioavailable … The bioavailability of 5-MTHF in supplements is the same as or greater than that of folic acid”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Health Risks from Excessive Folate; Table 3 ULs · read 2026-08-27
what it says
“(ULs) for Folate from Supplements or Fortified Foods … 19+ years 1,000 mcg … Large amounts of folate can correct the megaloblastic anemia, but not the neurological damage, that can result from vitamin B12 deficiency … might mask vitamin B12 deficiency”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Folate and Health — Cardiovascular disease and stroke · read 2026-08-27
what it says
“Folic acid (and vitamin B12) supplements lower homocysteine levels. However, these supplements do not actually decrease the risk of cardiovascular disease, although they appear to provide protection from stroke”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Interactions with Medications · read 2026-08-27
what it says
“Methotrexate … is a folate antagonist … the supplements could interfere with methotrexate’s anticancer effects … Antiepileptic medications … can reduce serum folate levels … folate supplements might reduce serum levels of these medications … Sulfasalazine … inhibits the intestinal absorption of folate”
- NIH ODS — Folate Fact Sheet for Health Professionals (updated November 30, 2022; read via archive.org capture, see verify_notes) — Groups at Risk — alcohol use disorder; MTHFR polymorphism · read 2026-08-27
what it says
“alcohol interferes with folate absorption and hepatic uptake, accelerates folate breakdown, and increases its renal excretion … (CDC) recommends 400 mcg/day of folic acid, not 5-MTHF, for people who could become pregnant, even if they have a 677C>T MTHFR polymorphism”
- FDA — Daily Value on the Nutrition and Supplement Facts Labels, Reference Guide: Daily Values for Nutrients (content current as of 03/05/2024) · read 2026-08-27
what it says
“DVs are the recommended amounts of nutrients to consume or not to exceed each day … Folate/Folic Acid … 400mcg DFE”
- HSA Singapore — Health Supplements Guidelines GL-CHPB-3-001 Rev. No. 020, January 2026 — clause 4.8, Table 4 Vitamins Limits, clause 4.11 + List of Health Claims · read 2026-08-27
what it says
“HS for use by the general adult population should not contain vitamins and minerals exceeding the stipulated limits … Folic acid 0.9mg … Contribute to normal homocysteine metabolism • Folic acid, vitamin B6, B12 … Increase maternal folate status • Folic acid”
- HSA Singapore — Guidelines on Prohibited and Restricted Ingredients in Health Supplements and Traditional Medicines GL-CHPB-1-012 Rev. No. 001, October 2025 — Annex A row 47 · read 2026-08-27
what it says
“47. Folic acid … not provide more than 0.9mg … When for oral use by pregnant women to prevent against recurrence of neural tube defects or for patients with folic acid deficiency … “This product must be used under recommendations by healthcare professionals.””
- iHerb Singapore — category page Vitamin B9 (Folate - Folic Acid), default order, 130 results · read 2026-08-27
what it says
“California Gold Nutrition, Folinic Acid, Alcohol Free … Jarrow Formulas, Vegan Methyl Folate, 400 mcg … NOW Foods, Folic Acid, 250 Tablets … Doctor's Best, Fully Active Folate 400, 400 mcg … Life Extension, BioActive Folate & Vitamin B12”
Updated 2026-08-29. Every line above traces to a numbered source. Kozen-X is not a medical device and does not give medical advice. It lists what published sources have written down — nothing more. A pair not listed is unrecorded, not cleared. Before you start, stop or re-time anything, talk to your doctor or pharmacist.