Why can my son ea foods hes allergic to only if its prcessed but not natural?

Food processing. When foods are processed, oftentime by heating, the proteins are frequently altered and rendered less allergenic. Such is the case in the oral allergy syndrome where various fresh fruits that when eaten raw cause oropharyngeal pruritus and/or swelling, if cooked or processed they are well tolerated without causing symptoms.
See full answer. Cooking some foods makes them less able to cause allergic reactions because cooking the food splits the food into smaller pieces that may not trigger an allergic reaction. But not all foods are safe after cooking. You need to check with an allergist to make sure whether processed foods are safe for your child.