Frequently Asked Questions

The diagnosis of a food allergy can be confusing for patients and their families alike. However, educating yourself about food allergy can alleviate your concerns.

A food allergy is when your body’s immune system reacts to a food protein because it has mistaken that food protein as a threat. Symptoms can range from mild to life-threatening.

Food allergies involve your immune system and can be life-threatening. An intolerance is when your body has trouble digesting a food. It can make you feel bad, usually with an upset stomach, but it is not life-threatening. The most common intolerance is to lactose—which is a natural sugar found in milk.

More than 170 foods are known to cause food allergies, but eight foods account for 9 out of 10 reactions in the United States. They are milk, eggs, peanuts, tree nuts, soy, wheat, fish and shellfish.

An allergic reaction to food can have many different symptoms, and a single person can experience different symptoms from one reaction to the next. Many reactions start with skin symptoms, like hives or a rash, but some do not. More serious symptoms like a drop in blood pressure and trouble breathing can be life-threatening. Talk to your allergist and work with them to fill out a Food Allergy & Anaphylaxis Emergency Care Plan to be prepared in an emergency.

Anaphylaxis is a serious allergic reaction that comes on quickly and may cause death. Early use of an epinephrine auto-injector is the primary treatment for anaphylaxis. A complete list of the symptoms of anaphylaxis and more information are available here.

No. While antihistamines can help relieve some mild symptoms from an allergic reaction, such as an itchy mouth or hives, they cannot stop the life-threatening symptoms of anaphylaxis.

Even trace amounts of a food allergen can cause a reaction in some people with food allergies. Although ingestion is the primary cause of severe reactions, in some cases, skin contact or breathing in a food protein (e.g., steam from cooking shellfish) can cause symptoms.

Symptoms usually start as soon as a few minutes after eating a food and as long as two hours after. In some cases, after the first symptoms go away, a second wave of symptoms comes back one to four hours later (or sometimes even longer). This second wave is called a biphasic reaction. The risk of a biphasic reaction is why patients who have a severe reaction should stay at a hospital for four to six hours for observation.

Anyone who has a food allergy can have a severe allergic reaction to food. However, having asthma puts you at higher risk. Fatal outcomes of anaphylaxis include a disproportionate number of teens and young adults, possibly because they take more risks with their food allergies (eating dangerously and delaying treatment).

No. Someone whose reactions have been mild in the past may suddenly experience severe reactions that could be deadly.

As many as 32 million Americans have food allergies, including nearly 6 million children.

The Centers for Disease Control and Prevention have reported a 50 percent increase in the number of children with food allergies since the late 1990s. Many theories have been suggested as to why the number of people with food allergies is growing, but scientific research has not yet found the cause.

Not yet. Strict avoidance of the food allergen is the only way to prevent a reaction and an epinephrine auto-injector is the only medicine to stop a severe reaction called anaphylaxis.

Peanut, tree nut, fish and shellfish allergies usually are lifelong. Milk, egg, wheat and soy allergies usually begin in childhood and eventually may be outgrown.