Taking 400 mcg of folic acid every day, starting before pregnancy, can reduce the risk of a baby developing neural tube defects in the early stages of development. Research from the National Institutes of Health suggests that taking folic acid before getting pregnant may help reduce the risk of developing gestational, or pregnancy-related, diabetes.

The study was conducted by the National Institutes of Health.

Gestational diabetes is a temporary condition that occurs during pregnancy when blood sugar, or glucose, levels rise too high. This happens when your body doesn’t produce enough insulin, or if the cells have a problem responding to it.

Gestational diabetes is a condition that needs to be diagnosed and treated quickly. It increases the mother’s chance for cesarean delivery and for blood pressure disorders. After pregnancy, it raises the risk of cardiovascular disease and type 2 diabetes.

For the infants, gestational diabetes increases the risk of large birth size and of obesity during childhood and adulthood.

Researchers analyzed questionnaire data on almost 15,000 women enrolled in a long-term study looking at diet, lifestyle, and disease.

During the study, the combined number of pregnancies for all the women reached more than 20,000. Of those pregnancies, women developed gestational diabetes in just more than 800 of them. Researchers learned that women who regularly took up to 400 mcg of folic acid each day before getting pregnant were 22% less likely to develop gestational diabetes, than those who did not.

Researchers did not find a lower risk of gestational diabetes connected to the consumption of foods high in folate.

It’s not clear why folic acid impacts gestational diabetes risk, but lack of folate in the diet has been associated with insulin resistance, a precursor to type 2 diabetes in people who aren’t pregnant, the researchers noted.

What this means for you

This was an observational study, which means it found a link but cannot prove that folic acid prevents gestational diabetes. More research is needed. But it adds to the reasons to follow the CDC’s recommendation that anyone who could become pregnant get 400 mcg of folic acid every day. The U.S. Preventive Services Task Force recommends starting at least one month before conception and continuing through the first two to three months of pregnancy.

If you’re pregnant or planning a pregnancy, talk with your provider about gestational diabetes testing and what you can do to lower your risk.

Updated October 2026. This article is for general information and is not a substitute for advice from your health care provider.

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