Women with no nut allergy who ate nuts during pregnancy had children with less risk of developing peanut or tree nut allergies, US researchers say. Dr. A. Lindsay Frazier of the Dana-Farber Children's Cancer Center in Boston and colleagues examined the association between pregnant mothers eating peanuts or tree nuts and the risk of nut allergies in their children. Study participants included children born to mothers who previously reported their diet during, or shortly before or after, their pregnancy as part of the ongoing Nurses' Health Study II. The study involved 8,205 children and the researchers identified 308 cases of food allergy, including 140 cases of peanut or tree nut allergy. The study, published in JAMA Pediatrics, found children whose non-allergic mothers had the highest peanut/tree nut consumption -- five times a week or more -- had the lowest risk of peanut/tree nut allergy. This lower risk of peanut/tree nut allergy was not observed among the children of mothers who had a peanut/tree nut allergy. "Our study supports the hypothesis that early allergen exposure increases the likelihood of tolerance and thereby lowers the risk of childhood food allergy. Additional prospective studies are needed to replicate this finding," Frazier said in a statement. "In the meantime, our data support the recent decisions to rescind recommendations that all mothers avoid peanuts/tree nuts during pregnancy and breastfeeding."