A food allergy is an abnormal response to a food by your immune system. A food allergy may cause itching and swelling; red, raised skin bumps (hives); wheezing or trouble breathing; and in rare cases, severe anaphylaxis, which can be life-threatening.

True food allergies are rare. Most reactions to foods are caused by food intolerances, reactions to food additives, or food poisoning. Food allergies are most common in children, but most children outgrow food allergies within a few years.

Foods that most often cause allergic reactions are:

• Peanuts.
• Tree nuts such as walnuts and almonds.
• Shellfish and fish.
• Eggs.
• Wheat.
• Soy products.
• Milk.