Learning Early About Peanut Allergy (LEAP)
Published in 2015, the Learning Early About Peanut Allergy (LEAP) study transformed the guidance that pediatricians and allergists/immunologists give to parents about when to introduce peanut foods to children at high risk for food allergies. The LEAP study was inspired by the observation that, among children of Jewish heritage, peanut allergy was ten times more common in the UK, where peanut introduction was delayed, compared to Israel, where peanut-based puffs are a popular baby snack. Could eating peanut early in life protect against peanut allergy?
Funded in part by FARE, the LEAP study followed more than 600 children for more than four years to answer that question. Babies enrolled in the LEAP study were at high risk for developing peanut allergy because they already had severe eczema, egg allergy or both. Importantly, the study did not include children who already had peanut allergy. LEAP studied peanut allergy prevention, but did not address treatment.
Starting at age 4-10 months, babies in the LEAP study were split into two groups. One group avoided peanut foods, while the other group was given age-appropriate peanut foods several times a week. By age 5, the children who had started eating peanut as infants were much less likely to be allergic to peanut.
For babies at high risk for peanut allergy, eating peanut foods early and regularly reduced the risk of peanut allergy by more than 80 percent, compared to peanut avoidance.
Persistence of Oral Tolerance to Peanut (LEAP-On)
Partially funded by FARE, the Persistence of Oral Tolerance to Peanut study, also called LEAP-On, followed children who had participated in LEAP to ask what would happen if children who ate peanut foods from an early age avoided peanut for a full year. Would their risk of developing peanut allergy increase if they didn’t eat peanut?
The answer was no. Children who ate peanuts from infancy to age 5 and then avoided peanuts from age 5 to age 6 were still 74 percent less likely to have peanut allergy than children who had consistently avoided peanut foods from infancy to age 6. LEAP-On showed that the peanut tolerance promoted by early introduction to peanut foods could be long-lasting.