The patient typically already has a history of atopy and an atopic family history. Eczema, otolaryngeal symptoms of hay fever or asthma will often dominate leading to the food allergy being unsuspected. Often well-cooked, canned, pasteurized, or frozen food offenders cause little to no reaction due to denaturation of the cross-reacting proteins,[6] causing delay and confusion in diagnosis as the symptoms are elicited only to the raw or fully ripened fresh foods.