Children born to mothers who have high levels of lead in their blood have a higher likelihood of being overweight and obese, compared to children whose mothers have low levels of lead in their blood. However, authors of the study believe that taking folic acid can reduce the risk of obesity in women with high lead levels in their blood.

That’s according to a recent study conducted by Xiaobin Wang, M.D., of the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland.

Researchers began by looking at data from the Boston Birth Cohort, a large observational study that aims to determine the causes of preterm birth.They analyzed blood samples from 1,442 mothers for lead exposure 24 to 72 hours after they gave birth. They then periodically measured the weight of a child from each mother throughout childhood.

At an average age of 1.8 years old, children born to mothers with high lead levels were more than four times as likely to be overweight or obese than children born to mothers with low lead levels.

Early in the study, participating women answered a questionnaire where they indicated whether they had taken a supplement containing folic acid in the second and third trimesters of pregnancy. Researchers found that the child’s risk of being overweight or obese decreased in the women with high lead levels, if the mother had adequate levels of folate 24 to 72 hours after giving birth.

Study authors note that if their results are confirmed, offering folic acid to women who test positive for high levels of lead exposure could potentially reduce their children's risk of being overweight or obese.

The U.S. Preventive Services Task Force recommends all women of reproductive age consume 400 micrograms of folic acid (the synthetic form of folate) each day during, and at least one month prior to pregnancy, to help prevent neural tube defects.

The study wasfunded by the National Institutes of Health and Health Resources and Services Administration and appears in JAMA Network Open.