Food Allergy and Intolerance

Food allergies or food intolerances affect nearly everyone at some point. One out of three people either say that they have a food allergy or that they modify the family diet because a family member is suspected of having a food allergy. But only about three percent of children have clinically proven allergic reactions to foods. In adults, the prevalence of food allergy drops to about one percent of the total population.

This difference between the clinically proven prevalence of food allergy and the public perception of the problem is in part due to reactions called "food intolerances" rather than food allergies. A food allergy, or hypersensitivity, is an abnormal response to a food a that is triggered by the immune system. The immune system is not responsible for the symptoms of a food intolerance, even though these symptoms can resemble those of a food allergy.

It is extremely important for people who have true food allergies to identify them and prevent allergic reactions to food because these reactions can cause devastating illness and, in some cases, be fatal.

Allergies are an inherited predisposition. Generally, people with a food allergy come from families in which allergies are common - not necessarily food allergies, but perhaps hay fever, asthma, or hives.

Common Food Allergies

In adults, the most common foods to cause allergic reactions include: shellfish such as shrimp, crayfish, lobster, and crab; peanuts (a legume that is one of the chief foods to cause severe anaphylaxis, a sudden drop in blood pressure that can be fatal if not treated quickly); tree nuts such as walnuts; fish; and eggs.

In children, the pattern is somewhat different. The most common food allergens that cause problems in children are eggs, milk, and peanuts. Adults usually don't lose their allergies, but children can sometimes outgrow them. Children are more likely to outgrow allergies to milk or soy than allergies to peanuts, fish, or shrimp.

The foods that adults or children react to are those foods they eat often. In Japan, for example, rice allergies are more common. In Scandinavia, codfish allergies are more common.

page updated 9/29/04