The LEAP Study
Original Study
Du Toit G, Roberts G, Sayre PH, et al. Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy. New England Journal of Medicine. 2015;372:803–813.
A Note About the Study Design
The LEAP study was a randomized controlled trial, but the overall trial was open-label, meaning that parents and researchers knew whether a child had been assigned to eat peanut-containing foods or avoid peanuts. Double-blind, placebo-controlled food challenges were used to help determine whether children had developed peanut allergy.
LEAP-On Follow-Up Study
Researchers later followed the children to find out whether the protection associated with early peanut consumption would continue after the children stopped eating peanut for one year. The lower prevalence of peanut allergy persisted after that 12-month period of peanut avoidance.
Du Toit G, Sayre PH, Roberts G, et al. Effect of Avoidance on Peanut Allergy after Early Peanut Consumption. New England Journal of Medicine. 2016;374:1435–1443.
The Israel–UK Study That Helped Lead to LEAP
Du Toit G, Katz Y, Sasieni P, et al. Early Consumption of Peanuts in Infancy Is Associated with a Low Prevalence of Peanut Allergy. Journal of Allergy and Clinical Immunology. 2008;122(5):984–991.
LEAP-Trio: The Children as Teenagers
In 2024, researchers reported what happened when the original LEAP children were followed into adolescence. At about age 12, peanut allergy was present in 4.4% of children originally assigned to eat peanut, compared with 15.4% of those originally assigned to avoid peanut—a 71% reduction.
The protection lasted even though, after the original LEAP intervention ended, the children were free to eat or avoid peanut as they wished.
Du Toit G, Huffaker MF, Radulovic S, et al. Follow-up to Adolescence after Early Peanut Introduction for Allergy Prevention. NEJM Evidence. 2024;3(6):EVIDoa2300311.
Ruth Recommends
Looking for easy ways to introduce and regularly serve peanut to your baby? See my recommended peanut products and feeding options.