Emma asks, “My mouth gets itchy when I eat celery but my doctor says I am not allergic to celery. Please explain.”
Emma, this is not uncommon if you suffer from hay fever caused by pollen. You may eat an apple, or a celery stalk, and your mouth or throat may become itchy. This is a reaction when your immune system confuses the proteins in some fruits and vegetables with proteins found in pollen, which are similar. This is referred to as cross-reactivity and results in oral allergy syndrome (OAS) also known as pollen fruit syndrome (PFS).
OAS is a form of a contact allergic reaction that occurs upon exposure of the mouth and throat to raw fruits or vegetables. The most frequent symptoms include swelling or itchiness of the mouth, face, lip, tongue, and throat.
Different reactions may be based on different environmental allergies. Those allergic to grasses, ragweed, or birch tree pollen allergies, for example, may react to different foods.
Some foods that may trigger OAS are:
Birch Tree Pollen:
Pitted fruits (like peaches, plums, nectarines), carrots
Grasses:
Peaches, celery, tomatoes, melons, oranges
Ragweed:
Banana, melon, cucumber, zucchini
Symptoms are usually limited to the mouth and go away after the food is swallowed or removed and no treatment is needed. Because the proteins in these fruits and vegetables are sensitive to heating, many people affected by OAS can eat cooked fruits and vegetables. Some individuals, however, can extend beyond the mouth and can experience anaphylaxis.
If you have additional questions regarding nutrition and food allergies, please let me know.
--- Susan