Question

What causes an allergic reaction to certain types of natural on processed foods such as peanuts?

Answer 1

Along with peanuts and shellfish, tree nuts are one of the food allergens most often linked to anaphylaxis — a serious, rapid-onset allergic reaction that may be ... to determine the presence ofallergen-specific immunoglobulin E, an antibody that binds to allergens and triggers the release of chemicals that cause symptoms. 
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Answer 2

Usually they are affected by a certain PROTEIN in a food or ingredient, such as peanuts and/or shellfish.<span />