Allergies: When Foods Harm

At many schools peanut-butter sandwiches are no longer welcome. For a child with an allergy that time-honoured lunchbox favourite can be deadly. In fact, a study completed by Dr. Rhoda Kagan, researcher at The Montreal Children's Hospital of the MUHC, between 1998 and 2002 showed that the incidence of peanut allergies doubled in schools during that time. Kagan is currently repeating the study to see whether this trend has continued to evolve.

A relatively mild symptom of food allergy is redness around the mouth. More significant symptoms are hives, facial swelling, vomiting or breathing difficulties. While children may outgrow allergies to milk and soy, allergies to peanut, tree-nut, fish, seafood and sesame usually last into adulthood.

Assessing a potential allergy starts with a visit to the child's physician, who may provide a referral to an allergist for further testing, counseling and follow-up. "For small children, the best recourse is to avoid the problematic food, and then, as soon as they are old enough, we teach children to ask permission before eating anything," says Dr. Bruce Mazer, pediatric allergist at The Montreal Children's Hospital. Avoiding problematic foods includes meticulously reading labels. Research has shown that the most common incidences of allergic reactions are at home or at a relative's house. While being cautious parents should know what their children like and be able to present a safe alternative. It should be noted that casual exposures like inhaling or skin contact are not significantly harmful. Actually eating the problematic food is the danger.

Most importantly, parents, teachers and childcare workers must know how to handle a child with an allergy. Mazer makes this clear: "If someone has a known allergy or one that is potentially life-threatening they must carry an Epipen or Twinject (auto-injectable epinephrine) with them at all times. These devices are lifesaving because they will reverse the symptoms of a severe allergic reaction." Interestingly enough, young children are not most at risk of a severe allergy attack, but rather teenagers since they don't want to carry their epinephrine and are at an age where they feel invincible and want to try everything. "We must impress on them that they have a very serious condition that's not to be fooled with," says Mazer.

Other current research studies on allergies at the MCH include a study on how babies become allergic and another on how allergy antibodies get made and are remembered by the body. The hope is to eventually be able to halt or interrupt the allergic reaction. 

By Peggy Niloff