The old advice on peanuts was backwards

For decades, parents were told to keep peanuts, eggs, and other common allergens away from babies for as long as possible. It seemed logical: avoid the danger, avoid the reaction. But research flipped that thinking on its head. The landmark LEAP study (Learning Early About Peanut Allergy) found that babies at high risk who regularly ate peanut foods starting in infancy were dramatically less likely to develop a peanut allergy than those who avoided them.

The idea is early oral exposure: introducing small, safe amounts of an allergen while the immune system is still learning teaches the body to tolerate the food rather than fight it. Because of findings like these, guidelines now encourage offering common allergen foods — like smooth peanut butter thinned with water, well-cooked egg, or dairy — around the time a baby starts solids (roughly 4–6 months and developmentally ready), not years later.

A few practical notes: never give a baby whole peanuts or globs of nut butter, which are choking hazards — mix a small amount into a spoonful of purée or warm water. Introduce one new allergen at a time so you can spot any reaction. And if your baby has severe eczema, an existing food allergy, or a strong family history, talk to your pediatrician or an allergist before starting — some higher-risk babies benefit from a plan or a supervised first taste.