Folic Acid Fortification Not Linked to Infant Allergy Development

January 6, 2012

Yale researchers investigate a link between prenatal folic acid intake and asthma development in babies.

Ever since countries began requiring fortification of enriched grain products with folic acid in the 1990’s, rates of neural tube defects in infants have generally plummeted. But concern still lingers regarding folic acid and adverse health effects in infants. A new study on 1499 U.S. women, however, has found no link between folic acid intake during pregnancy and infant allergy development-at least when it comes to asthma.

The study was supported in part by grants from the National Institutes of Health.

Because folic acid performs as a methyl donor for the body, some scientists have warned that it could increase DNA methylation during early development, potentially resulting in allergy development in newborns. A previous paper linked folic acid supplementation by pregnant women to greater risk of wheezing and respiratory problems in their offspring.

Published in the January 2012 issue of the American Journal of Obstetrics & Gynecology, the newest cohort study collected data on folic intake in women from their first trimester of pregnancy. Their children were followed until they were six years old for cases of wheezing, whistling in the chest, and diagnosis of asthma. While 88% of women claimed to be supplementing with folic acid during their third month of pregnancy, and with 51% of women still supplementing one month before conception, researchers were unable to make an association between folic acid intake and asthma development.

“After adjustment for cofounders, there was neither evidence of any associations between categories of folic intake and childhood asthma nor evidence of a dose-response relationship for any time period,” concluded lead researcher Marit Martinussen, MD, PhD, of the Yale School of Public Health (New Haven, CT).

Martinussen added that previous research has found folic acid to reduce the risk of neural tube defects by 23% with 200 μg daily to as much as 85% with 5000 μg daily.