Have you ever noticed that certain fruits, like apple, kiwi, cherries, or vegetables like celery make your lips or mouth itch?
This can be a form of food allergy related to seasonal pollens, called oral allergy syndrome (OAS)
There are protein molecules (antigens) in certain foods that look structurally similar to the protein molecules in pollen. If your respiratory tract and sinuses are reactive to pollen, the mouth and throat can become sensitized to the look-alike antigens in these foods.
For example, those with birch pollen allergies may become sensitized to raw apple, almond, carrot, celery, cherry, hazelnut, kiwi, peach, pear, plum
Those with grass pollen allergy may become sensitized to celery, melons, oranges, peaches, tomato.
Those with ragweed allergy may find themselves reacting to banana, cucumber, melons, sunflower seeds, zucchini.
Refer to this chart of foods associated with OAS on the Food Allergy Canada website
Symptoms of OAS can include varying degrees of itching of the palate or lips, swelling of lips and tongue, and sometimes redness or blisters in and around the mouth. In its worse form, very rarely, swelling and tightening in the throat, difficulty swallowing and anaphylaxis. Reactions usually happen within 5-30 of eating the food and for the most part, dissipate quickly.
How to manage oral allergy syndrome?
-Often the antigenic potential of these foods is decreased by cooking or heating the foods before eating
-The antigenic potential of a trigger food can vary season to season, depending on the plant’s growing conditions and exposure to environmental stress such as pollution.
-Reactions to trigger foods can be more noticeable on high pollen days when the immune system is already sensitized. You may not react to the food in the same way in the winter months.
-Often the same over the counter remedies you’re using for allergies can be effective against oral allergy symptoms, though it’s generally wise to avoid eating these foods raw if you’ve noticed they consistently trigger OAS symptoms. If problems breathing or swallowing develop, this is always a medical emergency.
Having allergies to pollen doesn’t automatically assume you have OAS, nor does it assume you’ll react to ALL antigentically similar foods. However if you find yourself reacting sporadically to otherwise healthy foods, especially during the summer BBQ’s or while enjoying the great outdoors, OAS could be the culprit.