Oral Allergy Syndrome—Why Some People Are Allergic to Fruits and Veggies

This article was medically reviewed by Steffini Stalos, DO, who is board-certified in Pathology and Lab Medicine, on June 6, 2022.

My Mouth Sometimes Itches After I Eat Produce. Could I Be Reacting to the Pesticides?

While some studies have linked the rise in food allergies to exposure to particular pesticides over time, it's very rare to have a true allergic reaction to the pesticide residues that can remain on produce. That said, allergies are very individual, and there's no harm in trying out certified organic produce—which is free of synthetic pesticides—to see if that does the trick.

If going organic doesn't help, though, it is possible to be allergic to the fruits and vegetables themselves. Some people have what's called oral allergy syndrome, meaning they get reactions to certain proteins found in various fruits and vegetables.

For example, bananas, avocados, kiwis, and more can cause cross-reactions in people who are allergic to latex—an allergy you may not realize you have if you're not, say, a health care worker or someone who wears a lot of rubber gloves. Those who have allergies to birch, ragweed, or grass pollens may react to things like hazelnut, peaches, celery, sunflower seeds, and zucchini, to name a few.

Symptoms of oral allergy syndrome, also known as pollen food allergy syndrome, include an itchy mouth or scratchy throat after eating raw fruit or vegetables, according to the American College of Allergy, Asthma, and Immunology.

An allergist can do skin or blood tests to see which protein is causing your cross-reactions, and that can help you pinpoint foods to stay away from. Some people find that their symptoms occur only during allergy season or that they can, for example, eat apple pie without an issue but can't bite into a fresh apple. That's because cooking with high heat breaks down the problem proteins that cause the cross-reactions.

Itchiness may seem like a minor symptom now, but it's very important to sleuth out your triggers with your doctor and avoid the ones that bring it on. Even if you've had only a mild reaction in the past, in rare cases your reactions could lead to anaphylaxis, a dangerous type of reaction that can cause a severe drop in blood pressure and constricted airways.

Health's medical editor, Roshini Rajapaksa, MD, is assistant professor of medicine at the NYU School of Medicine.