Findings from recently published studies, including the LEAP study, have led to rapid acceptance of the introduction of peanuts during the first year of life. “This new philosophy is reflected in revised guidelines from national pediatric and allergy societies,” says Meghan Azad, PhD. “However, these recent studies and new guidelines do not address the role of breastfeeding and maternal ingestion of peanut.”

For a study published in the Journal of Allergy and Clinical Immunology, Dr. Azad, Tracy Pitt, MD, FRCPC, and colleagues performed a secondary analysis of data from a previous allergy and asthma study that tracked children born in 1995 from birth to age 15. “All infants in the study had an immediate family history of asthma or two relatives with immunoglobulin E-mediated allergic disease. Mothers were randomized during pregnancy to standard care (control) or a multifaceted intervention that included maternal peanut avoidance and delayed introduction of peanut and other allergenic foods. Infants were assessed at multiple time points throughout early childhood and tested for peanut sensitization at age 7.”

The researchers found, in this high-risk group of breast-fed children, an association between early peanut introduction in the first year of life and reduced risk of peanut sensitization by age 7. “But the association only occurred if mothers also consumed peanuts while breastfeeding,” stresses Dr. Azad. “Both exposures were necessary for this protective effect to occur.”

The study suggests that encouraging peanut consumption while breastfeeding in combination with early direct peanut exposure may decrease the risk of peanut sensitization in high-risk children, according to Dr. Pitt. However, “further research is needed to determine if the current findings for peanut sensitization also apply to clinical peanut allergy,” she adds. “These associations should also be investigated in other settings and contemporary populations.”


Meghan Azad, PhD, has indicated to Physician’s Weekly that she has no financial interests to disclose.

Tracy Pitt, MD, FRCPC, has indicated to Physician’s Weekly that she has no financial interests to disclose.


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