Cornelius W. Van Niel, MD

Children had substantially lower risk for nut allergies if their mothers ate nuts regularly around the time of pregnancy.

Even as the prevalence of childhood peanut and tree nut (P/TN) allergies rises, recent guidelines do not offer clear advice on whether introducing these allergens early in life or prenatally affects risk for such allergies (either positively or negatively). Researchers examined reported diet from women in the Nurses' Health Study II as well as later reports of food allergies in 8205 of their children. Dietary history determined P/TN intake within 1 year of pregnancy in 76% of mothers, and serial surveys showed that maternal P/TN consumption was generally stable regardless of pregnancy. Medical records were reviewed to confirm the children's allergy diagnoses and symptoms; 140 cases of P/TN allergy were identified.

Analysis adjusted for confounders showed that among the 98% of mothers who did not have P/TN allergies, those who consumed ≥5 servings of P/TN weekly during the peripregnancy period were substantially less likely than those who ate <1 serving monthly to have children with P/TN allergies (odds ratio, 0.31). Even 1 to 4 servings weekly significantly reduced this risk (OR, 0.56). Results were similar regardless of the children's age when first introduced to nuts.

Citation(s):

Frazier AL et al. Prospective study of peripregnancy consumption of peanuts or tree nuts by mothers and the risk of peanut or tree nut allergy in their offspring. JAMA Pediatr 2013 Dec 23; [e-pub ahead of print].

Gupta R. To eat or not to eat: What foods are safe to consume during pregnancy? JAMA Pediatr 2013 Dec 23; [e-pub ahead of print].