The Reason Your Mouth Itches After Eating Some Fruits
Eating fresh produce is a fantastic (and tasty) way to round out a healthy diet, but what if your favorite peaches, apples, or plums make your mouth or throat itchy? While it's natural to wonder if you're developing a true food allergy, if it's just itchy lips, tongue, mouth, or throat, and it happens every time you eat the same raw fruit (or vegetable), it's likely something called oral allergy syndrome (OAS), according to the College of Allergy, Asthma & Immunology.
It's annoyingly tied to pollen allergies, and if you're "lucky" enough to experience seasonal sneezes, OAS can happen because your immune system notes that the proteins in these various fresh fruits are very similar to those found in the pollen you typically react to in the form of seasonal allergies.
Your immune system, tricked by the similarities, directs an allergic response to the fruit or veggie. This leads to symptoms such as itchy mouth, scratchy throat, and swelling of the lips, mouth, tongue, and/or throat. Some people also experience itchy ears, and in some cases, hives can develop around the mouth.
These symptoms are typically confined to one area (your mouth) and do not affect people systemically, which means serious allergic reactions that accompany "regular" food allergies do not usually happen — although in rare cases, anaphylaxis can occur (the ACAAI reports that it's only been reported in a very small percentage of people who experience OAS).
If you experience what you think is either OAS or a true food allergy, it's a good idea to visit an allergist to find out for sure since true food allergies can be serious and life-threatening. Though there is no treatment available for OAS, it's usually not necessary anyway — once the fruit exits the mouth, whether by swallowing or spitting it out, symptoms usually resolve. However, many people with OAS just choose to avoid the food if the symptoms are annoying enough.
There is some good news, though — if the problematic food is consumed in cooked form, it's usually A-OK because the heat of the cooking process distorts the proteins in the food and the immune system is perfectly fine with this. If you're not cool with heating up a watermelon, though, you may just have to skip it, or otherwise deal with an itchy mouth.