Food Allergies and Asthma in Kids

What are food allergies?

Some bodies -- especially young ones -- react to certain foods as they would to dangerous intruders. Their immune systems unleash a barrage of chemicals against proteins in these foods, causing the misery known as an allergic reaction. If you or your spouse has ever suffered from a food allergy, there's a good chance your child will too. About 5 percent of children under age five and 4 percent of older kids have allergies of this kind.

Which foods cause allergic reactions?

People with food allergies usually react to just one or two specific foods. In children, cow's milk, eggs, and peanuts are likeliest to trigger reactions. Other potential troublemakers include wheat, soybean products, seeds, fish, shellfish, and tree nuts (such as walnuts and pecans). A few foods have an undeserved reputation for causing allergies. Strawberries, citrus fruits, and tomatoes very rarely trigger a reaction, and nobody is allergic to sugar.

How can I tell if my child is allergic?

If the allergy is mild, your child may develop a skin rash minutes or hours after eating the triggering food. Other common symptoms include hives, stomach cramps, diarrhea, and vomiting. Allergic reactions can also trigger asthma attacks and aggravate eczema (an itchy, scaly skin rash) in children who are susceptible to these chronic conditions. If you suspect a food allergy, check with your child's doctor. She may refer you to an allergist who can help determine which foods he needs to avoid. This is important, because food allergies can be deadly. If your child feels his lips and tongue swell and is having trouble breathing, he may be going into anaphylactic shock, which can lead to loss of consciousness and even death. Call 911 or take him to an emergency room immediately.

Keep in mind that certain foods can cause problems even if your child isn't allergic to them. For instance, some children have trouble digesting lactose, the sugar in milk. This is called a food intolerance or sensitivity. Although food intolerances (which may also be triggered by various food additives) can cause stomachache, diarrhea, and other symptoms, they aren't as serious as allergies. If your child is lactose-intolerant, he'll probably still be able to consume small amounts of dairy products without trouble, and even the worst reactions are never life-threatening.

How are food allergies treated?

The only way to beat them is to avoid the offending foods. This isn't always as easy as it sounds. If your child is allergic to cow's milk, scan food labels for terms like "casein," "whey," "lactalbumin," "caramel color," and "nougat." Call the manufacturer if you have any questions about a product's contents. If your child has an allergy to peanuts or tree nuts, you'll need to be especially alert. These allergies tend to be the most severe, and nuts are everywhere, especially in cookies and desserts. Teach your child to watch out for nuts in any form, and make sure he never trades lunches at school. The Food Allergy and Anaphylaxis Network provides excellent information to help you steer clear of hidden dangers.

Many doctors recommend that you keep potential food allergy triggers out of your child's diet while he's very young, especially if these allergies run in your family. Some experts believe that if a child isn't exposed to a potential trigger when he's most vulnerable, he may never become allergic to the food.

There are no allergy shots that can prevent reactions to foods. You can give your child an antihistamine to ease the symptoms of a mild reaction, and a doctor can help him learn to manage conditions like asthma or eczema. If the allergy is severe, the doctor will also give you a kit containing the drug epinephrine (adrenaline) and an easy-to-use needle. A quick shot can save your child's life if he goes into anaphylactic shock.

Will my child's allergies go away?

Children who are allergic to eggs, milk, wheat, or soy usually outgrow the problem, especially if the food disappears from their diets for a few years. With a little guidance from your doctor, you can usually bring the problem food back into your child's life. But be sure to start slowly; if your child was allergic to eggs, for instance, try offering him a few baked goods with eggs in the mix, not an omelet. Unfortunately, allergies to peanuts, tree nuts, fish, and shellfish generally don't go away.

Further Resources

Kids with Food Allergies. Asthma and Allergy.

Pantell, Robert H. M.D., James F. Fries M.D., and Donald M. Vickery M.D. Taking Care of Your Child: A Parent's Illustrated Guide to Complete Medical Care, Eighth Edition. Da Capo Lifelong Books.

References

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Rodriguez J, Crespo JF, Burks W, Rivas-Plata C, Fernandez-Anaya S, Vives R, Daroca P. Randomized, double-blind, crossover challenge study in 53 subjects reporting adverse reactions to melon (Cucumis melo). J Allergy Clin Immunol 106(5 Pt 1):968-972.

Nekam KL. Nutritional triggers in asthma. Acta Microbiol Immunol Hung 45(1):113-7. Review.

American Academy of Family Physicians. Food Allergies: Just the Facts.http://www.familydoctor.org/340.xml