By Allergen Bureau

Early Introduction can Prevent Peanut Allergy for the Long-Term

A recent study has shown promising results for peanut allergy prevention. Conducted over several years, the research suggests that introducing peanuts in the diet of infants can prevent the development of peanut allergies later in life.

The Learning Early About Peanut allergy (LEAP) study was first published in 2015, transforming the guidance that paediatricians, allergists and immunologists give to parents about when to introduce peanut foods to children at high risk for food allergies.

In a randomised trial, researchers demonstrated that consuming peanuts from infancy until age 5 significantly reduced the development of peanut allergies. A subsequent follow-up showed this effect persisted even after a year of not consuming any peanut. The latest phase of the study assessed the durability of this tolerance in participants at 12 years old, following periods where the amount and frequency of peanut consumption was chosen by the individual.

Out of the original 640 LEAP study participants, 508 were reassessed at 12 years old. The prevalence of peanut allergy remained significantly lower in those who consumed peanuts early on (4.4%) compared to those who had not consumed them in infancy (15.4%). This is despite participants in both groups reportedly avoiding peanuts for prolonged periods of time between the ages of 6 – 12 years.

The group who had been exposed to peanut in early life had lower levels of Ara h2-specific immunoglobulin E (associated with severe allergic reactions) and higher levels of peanut-specific immunoglobulin G4, indicating better immune tolerance.

The study concludes that introducing peanuts in infancy and continuing until age 5 can lead to lasting tolerance, significantly reducing the risk of peanut allergies into adolescence.

This follow-up work was funded by the US National Institute of Allergy and Infectious Diseases and others. Further details can be found on the clinical trials website.

Reference: Du Toit et al. Follow-up to Adolescence after Early Peanut Introduction for Allergy Prevention. NEJM Evid. 2024 Jun;3(6). DOI: 10.1056/EVIDoa2300311.