A food allergy happens when your immune system - your body's defense against germs - overreacts to a certain food as if it was harmful. If you have symptoms after eating certain foods, food allergy testing can help find out if your symptoms are caused by an allergic reaction to those foods. And it's important to find out because allergic reactions to food can be serious.
Most food allergy symptoms are mild and include skin rashes and abdominal (belly) pain. But sometimes, symptoms quickly develop into a life-threatening allergic reaction called anaphylaxis, or anaphylactic shock. Anaphylaxis is a medical emergency that may affect your whole body, including your breathing. And there's no way to predict when an allergic reaction may change from mild to serious.
If you have a food allergy, eating even tiny amounts of a certain food or ingredient can quickly trigger your immune system to react. Most food allergies are caused by:
- Milk
- Eggs
- Peanuts
- Tree nuts (including almonds, walnuts, pecans, and cashews)
- Soy
- Wheat
- Fish
- Shellfish
Food allergies are more common in children than adults. Most children will grow out of allergies to milk, egg, soy, and wheat. But if a food allergy begins in adulthood, it's likely to continue through life.
If you or your child has symptoms that could be from a food allergy, your or your child's health care provider will probably refer you to an allergist for testing. An allergist is a doctor who specializes in diagnosing and treating allergies and asthma.
The allergist will pick the type of food allergy test that's right for you or your child. Tests include skin tests, blood tests, and a test where you eat small amounts of a suspected food while a provider watches for signs of allergy.