You Might Have Oral Allergy Syndrome if These Foods Make Your Lips and Mouth Tingle

Updated: Jun. 29, 2022

Oral allergy syndrome is the most common food allergy, but why haven't we heard more about it? Here's what you need to know about the little-known allergy that's ruining your relationship with fresh seasonal foods.

If you’ve ever eaten something, say a peach or a carrot, and immediately felt your mouth start to tingle or your lips or tongue begin to swell, you may suffer from oral allergy syndrome. But what exactly is oral allergy syndrome? How do you know if you have it? And most importantly, what can you do to treat it?

Oral allergy syndrome is the most common type of food allergy among adults, according to Clifford Bassett, MD, founder and medical director of Allergy & Asthma Care of New York, and assistant clinical professor of medicine at NYU School of Medicine. “It may affect up to 5 percent of the population, and is clearly more prevalent among those with seasonal pollen allergies, specifically those who have an allergic sensitivity to tree, weed, and/or grass pollen,” Dr. Bassett says.

How does oral allergy syndrome work?

If you have seasonal allergies, certain foods trick your body into thinking it’s encountering its seasonal nemesis, in what’s known as a cross-reaction. The immune system recognizes the pollen and similar proteins in the food and directs an aggressive immune response at it, according to the American College of Allergy, Asthma, and Immunology. It’s most likely to happen with foods that are closely linked to certain pollens. For example, someone allergic to tree pollen may have an allergic reaction to kiwis or walnuts. Someone with a grass pollen sensitivity may have a reaction to melons or tomatoes.

The biggest oral allergy triggers are fresh or dried fruits, such as nectarines, peaches, cherries, apples, and vegetables, including celery, carrots, string beans, snap peas, and peppers, and even some nuts, like walnuts and almonds. Itching and/or swelling of the throat, mouth, tongue, and lips are the most common symptoms of oral allergy syndrome, which usually occur within minutes of eating.

How can you prevent it?

Unfortunately, the only way to completely prevent an allergic reaction is to not eat the food at all. But if you love carrots and can’t imagine giving them up, Dr. Bassett says there are ways to lessen the severity of the reaction. “In some cases, you may peel or cook (even microwave) the food, and that appears to reduce the likelihood of experiencing symptoms,” he adds. “There is also some data to indicate that many patients can see a lessening of symptoms after receiving allergy injections to those same seasonal pollens.” Some lucky people are able to cure their food allergies through allergy desensitization.

If you think you may have oral allergy syndrome, consider seeing an allergist who may be able to diagnose you right on the spot, possibly with a skin test. And if your reactions to certain foods—especially nuts—are severe, where it feels like your throat is closing up, call 911, as it could be a sign of anaphylactic shock, an extreme, often life-threatening allergic reaction. Next, check out other bizarre stuff you might be allergic to.