Pregnant women should take folic acid, a B vitamin, during pregnancy to prevent neural tube defects in their babies. Now a new study, in JAMA Pediatrics, has found that sufficient folic acid during pregnancy may reduce the risk for obesity in children.
Researchers studied 1,517 mother-child pairs, measuring the mothers’ folic acid blood levels at delivery and following the children through average age 6. After controlling for other variables in both mother and child, they found that compared with those mothers who had folic acid levels in the highest three-quarters, those with levels in the lowest one-quarter had a 45 percent higher risk for obesity in their children.
Folic acid may be especially beneficial for obese mothers. Among obese mothers with the lowest folic acid levels, the risk of obesity in their children more than tripled. But in children of obese mothers, the risk for obesity was 43 percent lower if their mothers were in the top three-quarters for folic acid levels than if they were in the bottom one-quarter.
Experts advise that all pregnant women take a 400-microgram supplement of folic acid daily. But the senior author, Dr. Xiaobin Wang, a pediatrician at Johns Hopkins, said that there is no perfect correlation between the supplement dose taken and blood levels. So “for an overweight mother, it’s probably worth the trouble to do a blood test,” she said. “It’s not an expensive test, and it’s important information. We try to make an individualized decision, and this is a more precise way to do it.”