Nature Made Folic Acid 400 mcg (665 mcg DFE) Review
#1 of 9 · Editor's Choice✓ Label verified · Supplement Facts read Sep 7, 2026Real retailer photo, cut out. Label unedited.
Buy it. The evidence-based prenatal folate default. Folic acid is the NTD-proven form, this hits the 400 mcg DFE target, and USP Verification confirms the label.
$11 approx~$0.04 / tablet
Why It Scores 8.4 — And The Label Line Behind Each Number
Form & Evidence Base
30% of scoreFolic acid is the specific molecule tested in the MRC (1991) and Czeizel (1992) randomized trials and endorsed by the USPSTF — no supplement form has stronger periconceptional evidence. Synthetic folic acid is highly stable and near-completely absorbed; it requires enzymatic reduction, but for the general population this conversion is not a meaningful bottleneck.
- Form
- Folic acid tablet
Dose vs Clinical Target
25% of score400 mcg folic acid (665 mcg DFE) sits squarely in the 400–800 mcg DFE prenatal window recommended by the CDC and ACOG.
- Dose
- 400 mcg folic acid (665 mcg DFE)
Third-Party Testing & Purity
20% of scoreUSP Verified — an independent audit of identity, potency and purity that most competitors on this list lack.
- Testing / Certification
- USP Verified, Gluten Free
Tolerability & Safety
15% of scoreNo unnecessary added ingredients or sugar. Requires enzymatic conversion, which a small subset with severe MTHFR variants may prefer to bypass.
Value
10% of scoreAround $0.04 per tablet with a 250-count bottle; nothing here is cheaper per proven microgram.
- Count
- 250 tablets (~8 month supply)
- Cost per dose
- ~$0.04 per tablet
Label verified. Every figure read from the Supplement Facts photo, Sep 7, 2026.
Marketing Claims Vs. Reality
Folic acid reduces the risk of neural-tube defects
The MRC Vitamin Study (Lancet 1991, PMID 1677062) and Czeizel & Dudás (NEJM 1992, PMID 1729621) both showed folic acid supplementation significantly lowered NTD risk; a 2015 Cochrane review (PMID 26662928) confirmed the effect.
USP Verified guarantees the label is accurate
USP Verification independently confirms identity, potency, and purity at the time of audit, which is stronger than most competitors — but it is a manufacturing-quality mark, not proof of clinical benefit.
What Our Test Actually Found
Folic acid, not methylfolate, is the trial-proven form
Every major NTD-prevention trial used folic acid. Methylfolate raises blood folate effectively but has never been tested for NTD prevention in a randomized trial, so switching forms trades proven protection for a marketing claim.
USP Verification is the differentiator here
Folate label accuracy matters when the outcome is a birth defect. USP's independent audit puts this ahead of otherwise-similar folic acid tablets that carry only self-attested GMP claims.
Full analysis: all pros & cons (7), buy if / skip if
- Exact form and dose used in the landmark NTD-prevention trials
- USP Verified — independent confirmation of the label
- Extremely low cost per day (~$0.04/tablet)
- 250-count bottle lasts roughly eight months
- No unnecessary added ingredients or sugar
- Requires enzymatic conversion, which a small subset with severe MTHFR variants may prefer to bypass
- Plain single-nutrient tablet — not a full prenatal multivitamin
- Exact form and dose used in the landmark NTD-prevention trials
- USP Verified — independent confirmation of the label
- Extremely low cost per day (~$0.04/tablet)
- Requires enzymatic conversion, which a small subset with severe MTHFR variants may prefer to bypass
- Plain single-nutrient tablet — not a full prenatal multivitamin
Folic acid is the NTD-proven form, this hits the 400 mcg DFE target, and USP Verification confirms the label. For the vast majority of women — including most with MTHFR variants — this is all you need.
If you are trying to conceive or in early pregnancy, this is the default the evidence actually supports. Plain synthetic folic acid is the form used in the landmark MRC and Hungarian trials that established folate's protection against neural-tube defects (NTDs) — no methylfolate product has ever matched that trial record. Nature Made delivers 400 mcg of folic acid (665 mcg DFE) in a USP Verified tablet, meaning an independent body has confirmed the label. At roughly $11 for 250 tablets it costs a few cents per day. This is the boring, correct answer, and it earns the top spot precisely because it does not chase the methylfolate marketing story.
The right answer for almost everyone
For preconception and early-pregnancy folate, this is the evidence-based pick: the proven form, the correct dose, and an independent quality seal, all for a few cents a day. Pair it with a prenatal multivitamin for iron, iodine and B12, but for the folate component specifically you cannot do better on evidence-per-dollar.
If This Doesn’t Fit — Try These
02NOW Folic Acid 800 + B-12
A near-perfect value play: the proven form, a sensible added B12, and the cheapest daily cost on the board.
04Solgar Metafolin 400
The best methylfolate here for anyone who genuinely wants the active form, with a bioidentical molecule at the right dose.
Quick Answers
Is folic acid or methylfolate better for pregnancy?
Folic acid. It is the form proven in randomized trials to prevent neural-tube defects. Methylfolate raises folate levels but has no NTD-prevention trial data, so for most women folic acid is the safer evidence-based choice.
Is 400 mcg enough?
Yes for most women — the CDC recommends 400 mcg of folic acid daily for anyone who could become pregnant. Some situations (prior NTD pregnancy, certain medications) call for higher doses under medical guidance.
Sources & Further Reading
2 peer-reviewed sources, each linked to PubMed
- [1] MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet. 1991;338(8760):131-7. PMID 1677062 — Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Folic acid supplementation reduced the recurrence risk of neural-tube defects by around 70%.
- [2] US Preventive Services Task Force. Folic Acid Supplementation for the Prevention of Neural Tube Defects: US Preventive Services Task Force Recommendation Statement. JAMA. 2017;317(2):183-189. PMID 28097362 — Folic Acid Supplementation for the Prevention of Neural Tube Defects. Recommends all people planning or capable of pregnancy take 400–800 mcg of folic acid daily.
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