An allergic reaction to food is usually your immune system overreacting to a protein.   Immunoglobulin E (IGE) tags the protein as destructive and starts attacking.  The reaction could range from mild to severe and can include skin issues (rash, hives), digestive issues (stomach pain, vomiting, diarrhea) and/or respiratory issues (cold symptoms, wheezing, anaphylaxis).  In the United States, allergic reactions to food account for 30,000 emergency room visits and 100-200 deaths per year.

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