A large cohort analysis of allergic outcomes from peanut and tree nut consumption during pregnancy

Current research has challenged the conventional wisdom of dietary avoidance of food allergens during pregnancy. A recent study from the UK found that avoidance of peanuts, specifically, during pregnancy did not confer significant protection from peanut allergy to the infant. Accordingly, the UK removed that recommendation. In the US, avoidance is only recommended for children at risk by heredity.

In this issue, Maslova et al. (J Allergy Clin Immunol 2012;130:724-732) from Center for Fetal Programming, Statens Serum Institut, present important results from an analysis of a very large Danish birth cohort (n=61,908). The authors look at development of asthma, wheeze, and allergic rhinitis – not food allergy – in children whose mothers consumed peanuts and tree nuts during pregnancy as compared to children whose mothers avoided these foods.

At 18 months, children whose mothers ate peanuts more than once a week were less likely to have parent-reported asthma, while children whose mothers ate tree nuts were less likely to report asthma, wheeze and recurrent wheeze. At 7 years, children of mothers who ate peanuts and/or tree nuts were less likely to have a registered diagnosis of asthma. These results all reached statistical significance. The association of tree nut consumption during pregnancy with decreased likelihood of self-reported allergic rhinitis during the first 7 years of life was borderline statistically significant.

Maslova et al conclude by suggesting that their results do not support avoidance or decreased consumption of peanuts and tree nuts during pregnancy.