- Blood folate concentration is the amount of folate that can be measured in the blood (many forms of folate are included in the measure). When a woman gets folic acid through fortified foods or supplements, her blood folate concentration increases. Having enough folate in the blood can reduce her risk of having a baby affected by a neural tube defect.
- Once a woman starts consuming 400 micrograms (mcg) of folic acid every day, it can take several months for her to have a blood folate concentration that is high enough to help prevent neural tube defects.
- The two most important factors that determine whether a woman has a blood folate concentration that is high enough to help prevent neural tube defects are the amount of folic acid consumed each day and the length of time it is consumed before pregnancy. When taking supplements, more is not necessarily better. The Centers for Disease Control and Prevention recommends women take 400 mcg of folic acid every day, starting at least one month before getting pregnant.
- Folic acid is absorbed easily by the body, and studies have shown that it can increase blood folate concentrations (the amount in the blood) across populations (including those with the MTHFR TT genetic variant).