Larry Hand
December 23, 2013
Children may have a significantly lower risk for peanut or tree nut allergy if their nonallergenic mothers ate peanuts or tree nuts at least 5 times a week in peripregnancy, according to an article published online December 23 in JAMA Pediatrics. The study results support current guidelines for maternal diets.
A. Lindsey Frazier, MD, ScM, from the Dana-Farber Children’s Cancer Center, Boston, Massachusetts, and colleagues conducted a prospective cohort study of 10,907 participants in the Growing Up Today Study 2 (GUTS2), born between January 1, 1990, and December 31, 1994. The study population is composed of the offspring of women in the Nurses’ Health Study II (NHSII).
The researchers identified 308 cases of allergy to any food, including 140 physician-diagnosed cases of peanut/tree nut allergies among the participants. Participants in the GUTS2 study, which began in 2004, reported on their lifestyle and medical history by periodic questionnaires, including a food allergy questionnaire in 2009.
Diets, including intake of peanuts, other nuts, and peanut butter ranging from never to 6 times a day, of the nurses who were their mothers were attained by periodic questionnaires in NHSII. Maternal history of nuts consumption was for periods within 6 months of pregnancy.
In multivariable analyses, , offspring whose mothers were nonallergenic and who reported the highest intake of peanuts or tree nuts (≥5 times a week) had the lowest risk for allergy to those nuts (odds ratio [OR], 0.31; 95% confidence interval [CI], 0.13 – 0.75; P = .004), after adjusting for sex, race, other diseases, and age of mother at birth. The researchers found a nonstatistically significant increased risk for allergy among offspring whose mothers had a peanut or tree nuts allergy.
The researchers also observed that mothers who reported the highest consumption of peanuts or tree nuts were more likely to report the highest consumption of fruits and vegetables and were more likely to introduce peanuts or tree nuts to their children at younger ages. Rich in antioxidants, fruits and vegetables may also lower risks for allergies and asthma, the researchers write.
“Our study supports the hypothesis that early allergen exposure increases the likelihood of tolerance and thereby lowers the risk of childhood food allergy,” the researchers conclude. “Additional prospective studies are needed to replicate this finding. In the meantime, our data support the recent decisions to rescind recommendations that all mothers avoid [peanuts or tree nuts] during pregnancy and breastfeeding.”
In an accompanying editorial, Ruchi Gupta, MD, from the Northwestern University Feinberg School of Medicine, Chicago, Illinois, agrees with the researchers.
“[R]ecommendations regarding the ingestion of potentially allergenic foods during pregnancy have flip-flopped for more than a decade…. For now, though, guidelines stand: pregnant women should not eliminate nuts from their diet as peanuts are a good source of protein and also provide folic acid, which could potentially prevent both neural tube defects and nut sensitization. So, to provide guidance in how to respond to the age-old question ‘To eat or not to eat?’ mothers-to-be should feel free to curb their cravings with a dollop of peanut butter!”
This research was supported by Food Allergy Research and Education, New York. Dr. Young reported receiving royalties from his book, The Peanut Allergy Answer Book. The other authors nor Dr. Gupta have disclosed no relevant financial relationships.
JAMA Pediatrics. Published online December 23, 2013. Article full text, Editorial extract