The foods most likely to cause allergic reactions in adults include crustaceans such as shrimp, crayfish, lobster and crab, peanuts, tree nuts such as walnuts, fish and eggs. The foods most likely to cause reactions in young children are milk and eggs, wheat and peanuts.

Adults usually do not lose their allergies but children can sometimes outgrow them. Children are more likely to outgrow allergies to milk or soy than allergies to peanuts, fish or shrimp. An allergy to peanuts or shellfish may cause more severe reactions after the first exposures.

People are likely to react to foods that they eat often. In Japan, for example, rice allergy is frequent. Scandinavia has a high incidence of codfish allergy.