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Understanding Food Allergies

Food allergies are on the rise. In fact, about one-third of the 6 million people who suffer from food allergies in the U.S. are adults who often suffer in silence, not realizing that they are experiencing allergic reactions.

According to CBS News Health Correspondent Dr. Emily Senay, 90 percent of all true food allergies are caused by one of the following eight foods:

  • eggs
  • milk
  • soy
  • wheat
  • peanuts
  • tree nuts
  • fish
  • shellfish
Peanuts are the most common cause of fatal allergic reactions. But people can be sensitive to combinations of food

For example, tuna fish steak can cause a reaction, but tuna from a can can be perfectly safe. Or you may be all right eating beef or milk alone, but you get a reaction when you eat them at the same sitting. Also, some people have bad reactions to peanuts, but they have no reaction to peanut oil. So how a food is prepared can have an affect on allergies.

Many people claim to be allergic to a food. But a true allergy is quite different from a food intolerance, which is what most people really have. Food intolerance is mostly gastrointestinal in nature, though it symptoms are similar to those of food allergies. Food allergies are mediated by the immune system. Only testing by a doctor will help sort things out if there's a doubt.

To help distinguish between foods you just don't like, a food intolerance, and a true food allergy ask yourself the following questions:

  • After eating certain foods, do you break out into a rash, have itching, swelling, gastrointestinal problems, or trouble breathing?
  • Do symptoms appear within minutes or up to two hours after eating the food?
  • Do you have a history of asthma or allergies to other things?
  • Do allergies run in your family?
If you answer "yes" to any of these questions, then food allergy is more likely, as opposed to food intolerance, and you should talk to your doctor about testing to confirm the allergy.

Doctors don't know why allergies develop at all or why some develop later in life. But it is important for people to know that just because you weren't allergic to milk as a child, doesn't mean you can't be allergic to it as an adult. If you notice that you're having symptoms such as rash, itching, stomach problems or difficulty breathing, pay attention to them and see a doctor. Don't assume that it's an isolated instance.

Children have the highest rate of food allergies but often outgrow them. On the other hand, allergies developed in adulthood are often with you for life.

The "cure" for a food allergy is to avoid the food that causes the reaction. Immune therapy or allergy shots have not been proven to really work nor has oral desensitization helped in eliminating food allergies.

Bottom line: if you have a true food allergy, avoid the food.

Some people have the most severe form of food allergy, which is called anaphylaxis. That's when the throaswells and blocks the ability to breathe. People with anaphylaxis should always carry with them a form of injectable epinephrine and an antihistamine to be taken immediately if they feel a severe reaction coming on.

[For more information about food allergies, see The Food Allergy Network.]

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