For how we live.
The LEAP trial found that feeding peanut to high-risk babies from infancy cut peanut allergy at age five from 13.7% to 1.9%. A follow-up showed the protection held — but high-risk infants should be assessed first.
Two birth cohorts totalling 9,801 children were sorted into eight developmental patterns. The classic progression was one of them, and one of the smallest.
Both things are true, and both rest on high-certainty evidence. The phase 3 trial and the meta-analysis that followed it measured different outcomes and reached opposite-sounding conclusions.
The LEAP trial cut peanut allergy in high-risk infants from 13.7% to 1.9%. A second trial found the benefit real but harder to achieve — and only in children who actually ate the food.
The LEAP trial reversed a generation of avoidance advice. A second trial run in the general population missed its primary endpoint, and the distance between those two results is the part usually left out.