Have you ever experienced itchiness or hives in your mouth area after eating raw fruit or vegetables? Do you also have seasonal allergies?
If so, you may have oral allergy syndrome, whose symptoms occur because the proteins in some fruits and vegetables are similar to proteins in some pollens.
"They're not identical proteins, but they're similar enough to confuse the immune system to have these reactions," said said Dr. Robert Wood, chief of pediatric allergy and immunology at Johns Hopkins Children's Center.
That's not to say that everyone with pollen allergies has oral allergy syndrome. A person may sneeze all spring long and not have any obvious food sensitivities.
But oral allergy syndrome may help explain why some people have seemingly mysterious reactions to certain foods -- for example, raw apples but not cooked apples. That's because there are proteins in raw apples that are very similar to the proteins in birch pollen, experts say.
Cooking the offending fruits and vegetables will "denature" or change the shapes of these proteins, so people with oral allergy syndrome will usually be able to eat them without a problem, said Dr. Stanley Fineman, allergist with the Atlanta Allergy and Asthma Clinic.