Peanut Allergy Risk Higher for Younger Siblings of Peanut-Loving Older Siblings, Study Finds

Young children may face an increased risk of developing a peanut allergy if their older siblings regularly consume peanuts, according to research presented at the American Academy of Allergy, Asthma & Immunology (AAAAI) annual meeting in Philadelphia. Yet, early introduction of peanuts to the younger sibling’s diet can mitigate this risk, researchers say.

Household Peanut Consumption and Sensitization

The study, led by Dr. Michelle Huffaker, an allergist and immunologist at Stanford University, revealed that children were 16 times more likely to become sensitized to peanuts and 13 times more likely to develop a peanut allergy if their families – particularly their older siblings – consumed more peanuts and peanut products. This risk was heightened for younger siblings with eczema, especially those who had experienced it for a longer duration.

Researchers followed younger siblings of children who had participated in the Learning Early About Peanut Allergy (LEAP) clinical trial. They assessed household exposure to peanuts based on the older siblings’ consumption habits.

Exposure Through Skin Contact May Play a Role

The findings support the hypothesis that children can become sensitized to foods, like peanuts, simply through exposure without ingestion – potentially through skin contact. However, this risk is significantly reduced when peanuts are introduced to a young child’s diet during their first year of life.

“These findings support the concept that peanut allergy can develop with exposure to peanuts through the skin, and that this risk can be overcome by introducing peanuts to the diet at an early age,” Dr. Huffaker stated in a press release from the AAAI.

Novartis Investigating Remibrutinib for Peanut Allergy

Alongside these findings, research into potential treatments for peanut allergy is ongoing. Novartis is currently evaluating remibrutinib, a Bruton’s tyrosine kinase inhibitor, in Phase II clinical trials focusing on IgE-mediated peanut allergy. The results of these trials were also presented at the AAAI meeting, with plans for a Phase III program in food allergy in the latter half of 2026.

Guidelines for Peanut Allergy Prevention

Current guidelines emphasize the importance of early food introduction, including peanuts, to reduce the risk of developing food allergies. The American Academy of Pediatrics (AAP) has published guidelines for early food introduction, and the AAAAI provides further information on peanut allergy prevention.

Findings presented at medical meetings are considered preliminary until published in a peer-reviewed journal.