How to use folate supplements: why to start before pregnancy and folate's role in methylation
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Written by: Shingo YoshizakiReviewed by: Tomonobu Someda
Why should you start taking folate supplements before getting pregnant?
Research shows that folic acid supplementation starting before conception and continuing into early pregnancy reduces the risk of neural tube defects by approximately 72%. Folate is an essential cofactor for DNA synthesis and methylation, and supplementation is widely recommended because dietary intake alone is often insufficient.
Strong evidence: a 72% reduction in neural tube defects
A Cochrane meta-analysis including 6,105 participants (De-Regil et al., 2015) found that periconceptional folic acid supplementation reduced the relative risk of neural tube defects (spina bifida, anencephaly, etc.) by approximately 72%. Since neural tube closure occurs around weeks 3–4 of pregnancy, supplementation must begin before pregnancy is confirmed.
- ~72%
- Relative risk reduction for neural tube defects
- 6,105 participants
- Meta-analysis sample size
Folate's role in the methylation cycle
Folate plays a central role in one-carbon metabolism (the methylation cycle). It is an indispensable cofactor for converting homocysteine to methionine, as well as for DNA methylation and synthesis. Individuals with MTHFR gene variants may have reduced efficiency converting folate to its active form (methyltetrahydrofolate), making active folate (methylfolate) supplements worth considering.
- 400–800 µg/day
- Recommended folic acid dose periconceptionally
Why diet alone is often insufficient
Folate is found in green leafy vegetables, legumes, and liver, but is readily destroyed by heat during cooking, and average intake in Japan often falls below recommended levels. The WHO and major health agencies recommend folate supplementation for all women planning pregnancy, with particular emphasis on the period from 4 weeks before conception through 12 weeks of gestation.
- 4 weeks pre-conception to 12 weeks gestation
- Critical supplementation window
Related research
Sources
Published:
Written by
Shingo YoshizakiSoftware Engineer / Research Writer at BODYDATA
An engineer's job is verification. I read the source before I trust gym lore — same as code.
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Reviewed by: Tomonobu Someda
Content reviewed from the perspective of coaching practice and supplement-industry experience
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