The food allergy challenge

By Amy Shelton, RD, Clinical Dietition

Itchy eyes, hives, rash, runny nose, abdominal pain, nausea, vomiting, diarrhea, swelling of the lips, face, and tongue: Does your child frequently experience one or more of these symptoms? If so, he or she may have a food allergy. One out of 20 children are allergic to one or more foods.

A food allergy is an abnormal response by the body's immune system. Sometimes the body mistakes a particular food protein as an intruder and produces antibodies against that food protein. When the food is eaten, histamine and other chemicals are released, causing allergic symptoms. Reactions to food can involve the respiratory tract, digestive system, and the skin. A more severe reaction is called anaphylaxis, which may include many of those symptoms previously mentioned, including a drop in blood pressure, unconsciousness, and even death if not treated.

A family history of food allergies puts your baby at risk for developing food allergies; however, delaying the introduction of certain foods can help to prevent, decrease the severity of, or delay the onset of food allergies. This allows the immune system to mature before it is exposed to foods that are more likely to cause an allergic reaction. These foods include cow's milk, egg, soy, peanut, nuts, wheat, fish and shellfish. If your child is at risk, delay giving these foods until after one year of age, and up to three years in the case of peanuts, fish and shellfish.

If you feel your child may have a food allergy, have her/him evaluated by a qualified medical professional. Eliminating food without knowing for sure can lead to needless restrictions and poor nutrition. There are several ways to test for allergies. A Radioallergosorbent Test (RAST) takes a sample of your child's blood and measures it for levels of antibodies. During the Prick Skin Tests, specific food proteins are introduced into the top layer of the skin by a "prick." Positive results are measured by a hive or reddening of the skin.

Please note that both of these tests can be inaccurate, with 50-60% of positive tests being false positive, meaning not necessarily a true allergy. Check with your doctor to see if an elimination diet would be a good way to determine whether your child has a true allergy after allergy testing. During an elimination diet you'd eliminate all suspected foods in their diet for 10-14 days. Then introduce them back one by one, looking for reactions to the food. Some children may be able to tolerate some amounts of those foods without a reaction, but not in abundance. Many children outgrow their food allergies; however, allergies such as peanuts and tree nuts are not often outgrown. If your child has had an anaphylactic reaction to a food, it may not be safe to introduce a food back into their diet. Always discuss diet and nutrition plans with a physician or nutritionist before making changes.

Common food allergies in children include milk, eggs, peanuts, soy and wheat. Fortunately, there are many products available to substitute for those common allergies. Soy, rice or almond milk can be substituted for cow's milk. Soy yogurt can replace regular yogurt. There are vegetable oil based margarines without dairy. Many types of bread do not contain wheat including oatmeal, rice, rye and corn. To substitute eggs in recipes, a mixture of baking powder and vinegar can be used. It is important to read and understand food labels so that you can look for hidden ingredients in foods, especially baked and processed products.

It is not always easy to plan meals for a child with food allergies. In fact, in can be a bit overwhelming. To help you select foods, substitute foods, and give you resources for products and recipes, contact a Registered Dietitian. By adjusting the diet and making substitutions that promote a balanced diet, you can manage your child's allergies while he or she properly grows and develops.