A food allergy is a reaction by the body's immune system to something in a food, usually a protein; the body mistakenly acts like it is a germ or some other invader, and does its best to defend itself.
While any food could possibly cause an allergy, certain foods are much more likely to do so. In children, the foods that most commonly cause allergic reactions are:
Most allergic reactions occur within 30 minutes of consuming the problem food. Often, the reaction occurs within 5 to 10 minutes, but it can occur as long as 4 to 6 hours after ingestion.
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