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?
MYTH: My mouth feels itchy when I eat raw fruits or vegetables, so I’m probably allergic to wax or pesticides
The Science: If you have washed the food appropriately and suffer from seasonal allergies, you more likely have Food-Pollen Syndrome (FPS) or Oral Allergy Syndrome (OAS). Certain proteins found in some fruits and vegetables are very similar to those found in pollen. Upon eating these foods, the proteins can confuse the allergic immune system and cause allergic symptoms referred to as cross-reactivity. Common symptoms include itchy mouth and throat, and in some situations upset stomach. Rarely it can lead to more significant symptoms, such as hives and vomiting. Because the protein that causes the symptoms is heat sensitive, most people with OAS can tolerate cooked versions of the foods.
Classic examples of cross-reactivities include birch pollen allergy and sensitivity to apples, pears, peaches, cherries, certain nuts, carrots and celery; ragweed pollen allergy and sensitivity to melons, bananas, potatoes and zucchini; and mugwort (seasonal fall weed) pollen allergy and sensitivity to garlic, onions, peppers, broccoli, cauliflower, and certain spices. So what can be done? If you have symptoms of OAS, avoid eating these raw foods, especially during the corresponding allergy season because in many patients, OAS worsens during the pollen season of the pollen in question. Peeling the food before eating may be helpful, as the offending protein is often concentrated in the skin. Another way to reduce symptoms is to bake or microwave the food because high temperatures break down the proteins responsible for OAS. Canned foods may also cause fewer symptoms than the raw versions. Unfortunately, none of these measures will cure the issue or prevent new sensitivities in the future. Some studies have shown that treatment with allergy shots can not only improve seasonal allergic rhinitis symptoms but can improve the symptoms of OAS through desensitization to the cross-reactive pollen protein.
The Verdict: The myth that you are allergic to pesticides on fruits is unlikely and BUSTED! Instead, the cause is likely stemming from either Food-Pollen Syndrome or Oral Allergy Syndrome. Any symptoms that suggest possible food allergy should be discussed with your allergist to determine the cause and best plan for you.
Jacqueline Ross MD
Allergy Partners of NJ