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The Facts About Food Allergies

Asking questions and being informed can help you cope
By
WebMD Weight Loss Clinic - Expert Column
Reviewed by Matthew Hoffman, MD

When I was young, I sometimes claimed an "allergy" to foods I did not like so I would not seem impolite if served one of my least favorite foods. These days, some people use the word "allergy" to describe any discomfort associated with food.

Real food allergies are no joke. Many Americans suffer from them and don't even know it. The reactions can range from mild irritations, such as hives, swelling, and gastrointestinal discomfort, to life-threatening situations.

Children are most likely to suffer from allergies, but adults have them, too. The primary food allergy culprits are milk, eggs, peanuts, tree nuts, wheat, soybeans, fish, and shellfish. Yet any food can cause a reaction if it contains ingredients that are not tolerated.

How Allergies Work

A food allergy triggers an immune response, which attacks the lining of the intestines and causes discomfort. People who are allergic to gluten (a protein found in wheat and other grains) often mistake their allergy symptoms, such as gas, diarrhea, cramping, and weight loss, for any number of gastrointestinal conditions.

It's not uncommon for food allergies to be misdiagnosed. If you suspect you have allergies, see your doctor. Most allergies can be diagnosed with skin tests, but you can have a negative skin test and still be allergic to a certain food. Accurately determining food allergies usually requires a medical evaluation and trial elimination diets.

Not all problems with food result from an allergy. Sulphites, lactose, and monosodium glutamate (MSG) are examples of food substances to which many people are intolerant or hypersensitive. This is not the same as an allergy but can cause similar symptoms. Allergies trigger immune responses, but the body's immune system is not responsible for the symptoms of food intolerance.

Foods containing sulphites say so on their labels, but it takes careful scrutiny to make sure there's no lactose or MSG in a food. Sulphites are not permitted in fresh foods but can be contained in processed potatoes, wine, frozen avocados, dried fruits, and bottled lemon juice.

Read Labels

The "cure" for food allergies -- eliminate the offending foods -- is not as easy as it sounds. Some foods are obvious, but others require careful reading of the ingredient list. For some, you may need to contact the manufacturer.

Understanding label terminology is key to avoiding food allergens. Milk may be referred to by its components "whey" or "casein," and eggs can appear on a label as "albumin." Avoiding breads and cereals is relatively easy for those with a gluten allergy. But traces of wheat can be found in some lunch meats, soy sauce, soups, malt vinegar -- even jelly beans. These minute amounts are not always listed on the ingredient panel.

On Jan. 1, 2006, the Food Allergen Labeling and Consumer Protection Act went into effect. This law requires manufacturers to identify wheat and other grains to which people may be sensitive on product labels. Potentially allergenic substances must be identified by commonly known names -- so no longer will you need to know that lactalbumin contains milk.

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