Food Allergies:
When Food Becomes the Enemy

 By Ray Formanek Jr.

网站来源：  http://www.fda.gov/FDAC/features/2001/401_food.html 

Imagine what it would be like if eating a peanut butter sandwich or some shrimp, or drinking a tall glass of milk left you vomiting, gasping for breath, and furiously scratching a fresh crop of hives. For some people with food allergies, that's reality.

 A food allergy, or hypersensitivity, is an abnormal response to a food triggered by the immune system. While many people often have gas, bloating or another unpleasant reaction to something they eat, this is not an allergic response. Such a reaction is thought to not involve the immune system and is called "food intolerance." Only about 1.5 percent of adults and up to 6 percent of children younger than 3 years in the United States--about 4 million people--have a true food allergy, according to researchers who have examined the prevalence of food allergies.

It's critical for people who have food allergies to identify them and to avoid foods that cause allergic reactions. Some foods can cause severe illness and, in some cases, a life-threatening allergic reaction (anaphylaxis) that can constrict airways in the lungs, severely lower blood pressure, and cause suffocation by the swelling of the tongue or throat. An estimated 150 Americans die each year from severe allergic reactions to food, says Hugh A. Sampson, M.D., director of the Elliot and Roslyn Jaffe Food Allergy Institute at Mount Sinai School of Medicine in New York City and a food allergy expert.

The Food and Drug Administration's Center for Food Safety and Applied Nutrition has made it a high priority to boost consumer and food industry awareness of food allergens. As part of these efforts, the FDA is conducting food allergen education programs for consumers and industry. The agency also is developing a strategy for clear, easy-to-understand labeling of food allergens.

The FDA's food allergy efforts include focusing on the eight most common food allergens: milk, eggs, fish, wheat, tree nuts, peanuts, soybeans and crustaceans (such as shrimp and crabs). Proteins in these eight major foods are estimated to cause 90 percent of the allergic reactions in the United States.