美国国家公共电台 NPR If Raw Fruits Or Veggies Give You A Tingly Mouth, It's A Real Syndrome

DAVID GREENE, HOST:

Many people complain this time of year about pollen 1 allergies 2. They get those itchy, watery 4 eyes, runny noses. You know what I'm talking about. But some people with seasonal 5 allergies have it worse. They develop allergic 6 reactions to common fruits and vegetables - everything from apples and bananas to carrots and cucumbers. NPR's Allison Aubrey examines this allergy 7 syndrome 8 that often goes undiagnosed.

ALLISON AUBREY, BYLINE 9: Several years back, Jessica Slattery began to notice a strange reaction every time she ate a banana.

JESSICA SLATTERY: So the first thing I would feel is a little itch 3 on my tongue, and my lips would start to swell 10. And then I'd feel it all the way down my throat. And it's just like a little tingle 11.

AUBREY: And the reaction got worse in late spring, right around the time her seasonal allergies to tree pollen kicked in. Now, at first, she didn't go to the doctor because the symptoms were mild and because nobody she knew had ever heard of a fruit allergy.

SLATTERY: I did have some friends who were like, how could you possibly be allergic to a banana?

AUBREY: It's true that fruits are not the top allergenic foods. The usual culprits are eggs, fish, nuts. But over time, Slattery noticed that her reaction to bananas - that itchy, tingly sensation - spread to other fruits too, like kiwis, apples and avocados. Now, ultimately, she was diagnosed with a condition called oral allergy syndrome. Here's physician Carah Santos. She's an allergist at National Jewish Health in Denver.

CARAH SANTOS: I do think that this is one of the most underreported and under-recognized conditions.

AUBREY: She says Jessica Slattery's story is familiar. People with seasonal allergies or hay fever can suddenly develop allergic reactions to many common fruits and vegetables that they've eaten for most of their lives with no problem. Santos says what happens with this condition is that the immune system gets tripped up. It mistakes the proteins found in fruits and vegetables for the plant pollens 12 that triggered the allergy in the first place.

SANTOS: We call it cross-reactivity. And that just means your immune system sees something as looking very similar to something it already reacts to.

AUBREY: Santos says it's not clear why the immune system suddenly starts reacting to foods that it has tolerated for years. That can happen in adolescence 13 or adulthood 14. And the tricky 15 part about diagnosing it is that the standard tests to detect food allergies often come back negative. That was Jessica Slattery's experience.

SLATTERY: I had testing through skin pricks 16 for everything that I felt that I was allergic to. And everything came back negative.

AUBREY: Slattery says she went to several doctors who told her she was not allergic to these foods.

SLATTERY: When they're telling you that they've done this test and it's negative, you're like, OK, well, then it must be me.

AUBREY: That's why when she finally got the diagnosis 17, she felt reassured 18. Doctors made the diagnosis simply based on her symptoms.

SLATTERY: It was like, OK, so this isn't in my head. It's really a thing. And, you know, for me, it was a lot of relief.

AUBREY: People with oral allergy syndrome are typically told to avoid the raw foods they react to. But what they can do is peel or cook the fruits or vegetables before eating them. For instance, if apples cause the reaction, applesauce may be OK. Or if bananas are the problem, try banana bread. Here's allergist Carah Santos.

SANTOS: Oftentimes, they're able to eat these foods simply because the cooking process can degrade the proteins that look like the pollens.

AUBREY: This is the approach Jessica Slattery's taken. She's had to give up a lot of raw fruits, but she's found plenty of workarounds to maintain a healthy diet. Allison Aubrey, NPR News.