Food allergies occur when your body's immune system over reacts to a substance in a food, usually a protein, your body sees as harmful. This sets off a chain reaction within your body. Symptoms can occur within minutes and are generally seen on the skin (hives, itchiness, swelling of the skin). Gastrointestinal symptoms may include vomiting and diarrhea. Respiratory symptoms may accompany skin and gastrointestinal symptoms, but don't usually occur alone. They can be mild–such as a runny nose or itchy eyes to severe and even life-threatening. Most food allergies develop early in life, and many are outgrown.
Anaphylaxis (an-a-fi-LAK-sis) is a serious allergic reaction that happens very quickly. Without immediate treatment – an injection of epinephrine (adrenaline) and expert care – anaphylaxis can be fatal. Symptoms of anaphylaxis may include difficulty breathing, dizziness or loss of consciousness. If you have any of these symptoms, particularly after eating, seek medical care immediately (call 911). Don't wait to see if your symptoms go away or get better on their own.
A food intolerance is not the same as a food allergy. An intolerance occurs when your body is unable to digest a certain component of a food, such as lactose, a sugar found in milk; monosodium glutamate; or sulfites, a preservative. Though symptoms of intolerance may be unpleasant, including abdominal cramping or diarrhea, they are not life-threatening.
To help you avoid allergens, the Food and Drug Administration has mandated food companies specify on product labels if any of the eight major allergens is contained in the food. Manufacturers can change ingredients of products without notice, so double-check ingredient labels every time you buy a food, even a familiar one. Cosmetics and beauty products also may contain common allergens such as milk, egg, wheat and tree nuts.
A dietitian can help you understand which foods are safe to eat and how best to avoid items that may cause a reaction. When foods are cut from your diet, you may be short-changing yourself on important vitamins and minerals. Ask your healthcare provider for a referral.
~ Academy of Nutrition and Dietetics, 2012