Food Allergies: Just the Facts

Many of the things we think we know about food allergy are really just myths--stories that we hear often but aren't based on science. This handout will help you learn the facts about food allergies.

Fact: Although 25 percent of people think they're allergic to certain foods, studies show that about only 6 percent of children and 2 percent of adults have a food allergy. A true food allergy is a reaction triggered by the immune system (the part of your body that fights infection). Far more people simply have a food intolerance, which is unpleasant symptoms triggered by food (but does not involve the immune system).

Fact: Although people can be allergic to any kind of food, most food allergies are caused by tree nuts, peanuts, cow's milk, eggs, soy, wheat, fish and shellfish.

Fact: A condition is called a food allergy when the immune system thinks a certain protein in a food is a "foreign" agent and fights against it. This doesn't happen with sugars and fats.

Fact: Milk allergy is much more common in children than in adults. However, most children outgrow the allergy by 2 or 3. Symptoms of milk allergy include hives, vomiting and breathing problems after consuming a dairy product. Many adults may experience symptoms similar to milk allergy, as adults often have trouble digesting the sugar in milk. This is called "lactose intolerance." It isn't a true allergy. The symptoms of lactose intolerance are bloating, cramping, nausea, gas and diarrhea.

Fact: Most people with food allergies are allergic to fewer than 4 foods.

Fact: The most common immediate symptoms of food allergy are hives (large bumps on the skin), swelling, itchy skin, itchiness or tingling in the mouth, a metallic taste in the mouth, coughing, trouble breathing or wheezing, throat tightness, diarrhea and vomiting. The person may also feel that something bad is going to happen, have pale skin because of low blood pressure or lose consciousness. The most common chronic illnesses associated with food allergies are eczema and asthma.

Fact: Natural foods cause the most allergic reactions. Studies have found that some food additives, such as tartrazine, or yellow No. 5 and aspartame (brand name: NutraSweet), an artificial sweetener, do cause problems in some people.

Fact: Children usually outgrow allergies to milk, eggs, soybean products and wheat. However, people rarely outgrow allergies to peanuts, tree nuts, fish and shellfish.

Fact: Food allergy can be fatal if it is severe enough to cause a reaction called anaphylaxis (say: "anna-phil-ax-iss"). This reaction blocks the airways and makes it hard for a person to breathe. Fast treatment with a medicine called epinephrine (say: "epp-in-eff-rin") can save your life. If you or your child has a severe allergy, your doctor might give you a prescription for epinephrine self-injection pens. Your doctor can show you how and when to use the pen. If your doctor thinks you might need to use this medicine, you'll need to carry one with you at all times.

A person having an allergic reaction should be taken by ambulance to a hospital emergency room, because the symptoms can start again hours after the epinephrine is given.

Once a true food allergy is diagnosed, avoid the food that caused it. If you have an allergy, you must read the labels on all the prepared foods you eat. Your doctor can help you learn how to avoid eating the wrong foods. If your child has food allergies, give the school and other caretakers instructions that list what foods to avoid and what to do if the food is accidentally eaten.