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    Mayo Clinic Minute: What happens to your body when you’re allergic to food?

What happens to your body when you have an allergic reaction to food?

Dr. Avni Joshi, a Mayo Clinic pediatric allergist and immunologist, asks, "How does food allergy happen is the first question?"

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Dr. Joshi says researchers are still working that out, but one theory has to do with babies who have the skin condition, eczema.

"The food gets introduced through the skin, and that causes an aberrant immune response. Instead of the food being tolerant, you start recognizing the food as an allergen."

When that food, such as a peanut, is introduced into diets later, the babies already have developed antibodies against that food.

"Many kids start having itching and throat closure. If a large amount is consumed, they can have vomiting. They can have head-to-toe hives, breathing difficulty and anaphylaxis."

Anaphylaxis happens when your immune system identifies a substance, such as peanuts, as foreign. This triggers cells called "mast cells" to release chemicals that cause many symptoms, including dilated blood vessels, low blood pressure, flushing, constricted airways, intestinal problems and even death.

If you're concerned about food allergies, talk to your health care provider.