“I think my 7-month-old might have a food allergy. We gave him yogurt (which he’s eaten many times before) and he broke out in hives. Benadryl helped. We decided to try again and he broke out again. What is going on?”

The number of children with food allergies in the United States has increased.

According to an October 2008 National Health Interview Survey conducted by the Centers for Disease Control and Prevention’s National Center for Health Statistics, four out of every 100 children have a food allergy.

“We’d love to figure out why, but they are more common in the U.S. than in any other country,” says Dr. Maria Streck of Carolina Family Care, a division of the Medical University of South Carolina. “We just don’t know.”

Streck, who specializes in allergies, explains what foods can cause allergic reactions, symptoms and common misconceptions about allergies in children.

Why

People won’t develop a food allergy the very first time they eat a certain food. In order to develop an allergy, a person must be exposed to the food at least once in order to develop antibodies in his system. That being said, a person can eat a particular food many times without any problems and then one day experience a reaction because the body has created antibodies against it.

Reactions

The most typical reaction is a rash or hives around the mouth, including redness and bumps. Sometimes the result is only hives and will go away. If the reaction progresses, however, it can develop into an anaphylactic reaction, which can cause more severe reactions including vomiting, diarrhea, shortness of breath and wheezing..

Main allergy culprits

The foods that most often trigger allergic reactions are eggs, milk, soy, wheat, corn, nuts, fish and shellfish. Experts suggest parents wait until their children are older before feeding them certain foods. Some experts recommend avoiding milk until age 1, eggs until age 2, and fish, shellfish, nuts and peanut butter until age 3. But some doctors think that advice is backfiring and believe that allergies might be developing because of these food recommendations.

Is it a true allergy?

Sometimes fruit can cause a reaction that isn’t an allergy. Chemicals in fruits can sometimes cause a rash or irritation, which can happen with strawberry-flavored yogurt. Strawberries in particular have a high histamine content. However, when the baby broke out after eating the yogurt again, it probably indicates the problem is the dairy in the yogurt, not the fruit.

Prevention

There is no cure for food allergies. The best way to handle food allergies is to avoid any foods known to trigger a reaction.

Outgrowing allergies

Some allergies aren’t lifelong and are outgrown, particularly milk and egg. So just because a 7-month-old baby is allergic to a food now doesn’t mean it’s going to be a lifelong allergy. That’s why it’s important to see an allergist to be tested for allergies. Doctors perform skin testing in the office for these foods and later follow up and retest to see if a patient has outgrown the allergies.

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