Food allergies can develop through eating, touching or inhaling specific foods that can trigger an immune response. In some people, a food allergy can cause severe symptoms or even a life-threatening reaction.

This guide outlines key information on food allergies, including the most common allergens, common symptoms, prevention methods, and how to respond in an emergency.

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The “Big 9” Common Food Allergens

The most frequent food allergens in the U.S. are referred to as the “Big 9.” These account for the majority of food allergy reactions:

  • Milk
  • Eggs
  • Fish
  • Shellfish
  • Tree nuts
  • Peanuts
  • Wheat
  • Soybeans
  • Sesame

Prevention Tips for Food Allergies

If you or someone in your household has a food allergy, take these steps to reduce the risk of a reaction:

  • Know the “Big 9” Allergens.
  • Avoid foods that can cause an allergic reaction.
  • Read food labels carefully, even on familiar products.
  • Store and label food allergens separately.
  • Wash hands thoroughly after handling a food allergen and before preparing allergen-free meals.
  • Prevent cross-contact!

Common Symptoms of Food Allergies

Allergic reactions can vary from mild to severe. Symptoms may include:

  • Tingling or itching in the mouth
  • Hives, itching or eczema
  • Swelling of the lips, face, tongue, and throat or other parts of the body
  • Belly pain, diarrhea, nausea or vomiting
  • Wheezing, nasal congestion or trouble breathing

In Case of an Emergency

  • Have an EpiPen or other auto-injector on hand to treat severe allergic reactions, such as anaphylaxis.
  • Seek emergency treatment if anaphylaxis symptoms develop (difficulty breathing, severe drop in blood pressure, rapid pulse, dizziness or lightheadedness).