Inspired by one of our favorite television shows, Allergy Myth Busters looks at a number of popularly held beliefs about allergy. But are these myths just urban legends or are they true?
THE MYTH: Kids will outgrow food allergies.
THE SCIENCE: When your child is diagnosed with food allergies, one of the first questions you want answered is, “Will he/she outgrow it?” That’s a question that doesn’t always have an easy answer.
Several factors contribute to a child outgrowing a food allergy. Factors that favor outgrowing the allergy include earlier age of initial allergic reaction, only having mild to moderate allergic reactions, being allergic to just one food, and having eczema as the only manifestation of the food allergy.
One of the biggest factors that determine whether a child might outgrow a food allergy is which type of food to which they are allergic. Children allergic to milk, egg and soy are most likely going to outgrow their allergies. However, children with allergies to peanuts, tree nuts, fish and shellfish will not likely outgrow their allergies.
Studies evaluating persistence of food allergy provide variable results. In a general population, 76% of children with IgE-mediated milk allergy outgrow it by age 3. However, when looking at children in an allergy clinic setting, just over 50% of infants diagnosed with cow’s milk allergy outgrow it by age 5. That number jumps to nearly 80% by age 16. About 50% of children with egg allergy outgrow it by age 6. With wheat allergy, in a general population, 80% outgrow the allergy by age 5, but it may take longer in highly allergic children. With most foods, the higher the level of specific IgE-antibody to the food (whether measured by skin prick test of blood test), the less likely the child is to outgrow the allergy.
Children with milk and egg allergy have been shown to tolerate baked milk and egg foods well before tolerating the less heated forms of these foods. Consuming the heated forms of the foods may even enhance the development of tolerance to other forms of those foods, helping them “outgrow” the allergy more quickly. This should only be attempted under the watchful eye of your board-certified allergist, however.
Peanut allergy, unfortunately, tends to be life-long, with only about 20-25% of children outgrowing it. Of those who do outgrow their peanut allergy, 80% do so by age 8 – but if they haven’t developed tolerance by age 10, they’re very unlikely to do so.
There is much less data on tree nuts and shellfish, but it’s widely considered that these allergies are usually life-long.
THE VERDICT: So is this myth confirmed or busted? It depends. That’s why it’s important to have regular follow-up visits scheduled with your Allergy Partners physician to monitor the condition and provide you with the most up-to-date guidance.
Dr. Stephen Shield
Allergy Partners of Hampton Roads