The Anatomy of a Food Allergy

Food allergy affects millions of people in the United States. Where U.S. children are concerned, one in 13 has experienced food allergy. It is the function of the immune system to identify germs, such as viruses and bacteria, and destroy them so they will not make you sick. Food allergy results when the body’s immune system mistakenly views harmless food proteins as threats and attacks them in ways that lead to uncomfortable or even health-jeopardizing symptoms.

Anatomy of Food Allergy

(Pixabay / Couleur)

Food Allergy

Food allergy is different from food intolerance, which is a non-allergic food hypersensitivity or simply a difficulty in digesting some types of food. With food allergy, the body’s immune system produces abnormally large amounts of antibodies, called immunoglobulin E or IgE, to fight off food allergens. This leads to the release of chemicals such as histamine which results in the development of allergy symptoms.


Histamine is a chemical compound produced by the immune system to fight the “enemies”—the allergens. Histamine acts like a security officer,ridding the body of menacing threats. This works great for germs, but, of course, not for allergens which aren’t actually true threats at all—just innocuous proteins found in foods. In its misguided efforts to protect your body, Histaminecauses inflammation of the eyes, skin, nasal and sinus cavities, airways and more. The result is a raft of symptoms that make you miserable.

How does histamine work?

Your immune system knows when you come in contact with an allergy trigger, and it launches a chain reaction to defend your body against the allergen. It sends signals to the mast cells, cells that are filled with basophil granules that release histamine and other substances during allergic reactions. Upon leaving the mast cells, histamine boosts the flow of blood in the areas of the body affected by the allergen, causing inflammation.

Histamine docks at the body’s receptors. If the allergens affect your nose, histamine will prompt the nasal membranes to produce more mucus. This explains why you get a stuffy or runny nose when you experience allergies.

Foods and Histamines

When you eat or drink something that contains an allergy trigger, histamine works in the digestive system to set off an allergic reaction. This may include vomiting, cramping, or abdominal pain. Other food allergy symptoms include hay fever, itching or swelling in the mouth or throat, hives and eczema, and coughing and wheezing. In severe cases, food allergies can launch an anaphylactic reaction which can be life threatening.