Folate vs Folic Acid vs Methylfolate
Folate, folic acid and methylfolate (5-MTHF) compared: what official advice says, what reviews argue for methylfolate, what MTHFR variants do and do not mean, and safety notes.
Content last updated . This page has not been medically reviewed.
The question
Folate, folic acid and methylfolate all appear on labels, and people often ask which one to choose, especially in pregnancy planning. Folate is the natural B vitamin in foods. Folic acid is the manmade form. [1] Methylfolate (5-methyltetrahydrofolate, or 5-MTHF) is the predominant natural form, and it is also sold as a supplement. [2] Official UK advice to prevent neural tube defects names folic acid. Reviews argue that methylfolate is a reasonable alternative, but we did not find trials showing it prevents more neural tube defects. There is no universal winner. For the full profile, see Folate (vitamin B9) and folic acid.The options side by side
| Option | What it is | What is documented | Evidence strength | Caution |
|---|---|---|---|---|
| Folate (food) | The natural form found in foods such as leafy greens and fortified cereals. [1] | UK adults need 200 micrograms of folate a day. [1] | Established nutritional role | Food folate is variably absorbed, according to one review. [2] |
| Folic acid | The manmade form used in supplements and fortified foods. [1] | Named in UK advice for preventing neural tube defects. [1] | Established recommendation (UK) | Doses above 1 mg a day can mask vitamin B12 deficiency. [1] |
| Methylfolate (5-MTHF) | The predominant natural form. [2] | Can raise folate levels; reviews argue it avoids some folic acid drawbacks. [2][3] | Promising but limited: reviews, no outcome trial found | Not named in the UK advice we read. Medicines still need checking. |
What each source says
| Question | What the source found | Strength of evidence |
|---|---|---|
| UK advice before and early in pregnancy? | A 400 microgram folic acid supplement daily until 12 weeks of pregnancy for women who are pregnant or could become pregnant. [1] | Established recommendation (UK) |
| Do some women need more? | Women at higher risk of a neural tube defect are advised to take 5 mg of folic acid a day until 12 weeks, after speaking to a doctor. [1] | Established recommendation (UK) |
| Can either form raise folate levels? | A review says supplemental folic acid or 5-methylTHF can effectively increase folate concentrations to the level considered protective. [2] | Biomarker, not birth outcomes |
| Is methylfolate "better"? | The same review calls 5-methylTHF a better alternative to folic acid, especially in countries without fortification. [2] A second review also favors 5-MTHF. [3] | Promising but limited: reviews arguing one side |
| Does MTHFR change the answer? | Some studies link MTHFR variants to a small increased risk of neural tube defects, but it remains unclear how they affect the developing brain and spinal cord. [4] | Insufficient evidence on form choice |
Why people consider methylfolate
Reviewers point out that unmetabolized folic acid appears in the bloodstream at doses above 200 micrograms and that people vary widely in how well they reduce folic acid. [2] They also argue that methylfolate has no tolerable upper intake level and does not mask vitamin B12 deficiency. [2] These are arguments from biochemistry. Proper evidence not found in the sources we read (two reviews and a MedlinePlus gene page, searched via PubMed on 2026-10-23) for a head-to-head trial showing fewer neural tube defects, or better health outcomes, with methylfolate than with folic acid. Treat the reviews as the authors' case, not a settled consensus.MTHFR in plain terms
MTHFR is a gene that provides instructions for making an enzyme called methylenetetrahydrofolate reductase. [4] Having a variant does not by itself mean you need a particular supplement form. One review argues that methylfolate overcomes metabolic defects linked to MTHFR variants, but that is the authors' view and not a trial result. [3] Talk with a clinician rather than choose a form from a gene result alone.Frequently asked questions
Is methylfolate better than folic acid?
Reviews argue it may be, mainly for people who convert folic acid poorly. [2][3] Official UK advice still names folic acid for preventing neural tube defects. [1] Proper evidence not found for a direct outcome comparison.
Do I need methylfolate if I have an MTHFR variant?
The MedlinePlus page we read does not say so. It says variants are associated with a small increased risk of neural tube defects and that the mechanism is unclear. [4] Ask a clinician.
Can I take too much folic acid?
The NHS says doses above 1 mg a day can mask B12 deficiency, and 1 mg or less is unlikely to cause harm. [1]
How much folate do adults need?
In the UK, adults need 200 micrograms of folate a day. [1] We could not read the US NIH Office of Dietary Supplements page, so we quote no US figure.
Which form is in prenatal vitamins?
We did not find a source that states which form prenatal products use, so check the label. See Prenatal and postnatal vitamins.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
How to read the evidence labels
Labels used on this page: established recommendation, promising but limited, insufficient evidence.
Safety and who should ask a clinician
- B12 masking. The NHS says folic acid doses above 1 mg a day can mask vitamin B12 deficiency, which can eventually damage the nervous system if it is not spotted, and that this is a particular concern for older people. [1] It also says 1 mg or less a day is unlikely to cause harm. [1] See Vitamin B12 deficiency.
- Pregnancy. The 5 mg amount is prescribed, after speaking to a doctor. [1] See Pregnancy and breastfeeding and Prenatal and postnatal vitamins.
- Medicines. One review notes that folic acid interacts with drugs that inhibit dihydrofolate reductase. [3] Ask a pharmacist about your own medicines; see How interactions work.
- Children, kidney, liver and surgery. Proper evidence not found in the sources we read for form-specific advice on these. Ask a clinician, and tell the surgical team about supplements: Supplements before surgery.
- Quality. Labels differ between products; see Quality testing and certifications.
References
- NHS, B vitamins and folic acid (UK). Read 2026-10-23.
- Is 5-methyltetrahydrofolate an alternative to folic acid for the prevention of neural tube defects? J Perinat Med, 2013 Read 2026-10-23.
- Folate, folic acid and 5-methyltetrahydrofolate are not the same thing. Xenobiotica, 2014 Read 2026-10-23.
- MedlinePlus Genetics, MTHFR gene (US). Read 2026-10-23.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.