ORLANDO, Fla. -

Our kids sometimes do whatever they can to avoid eating fruits and vegetables, including making up all kinds of excuses.

But, the next time they say that apples or carrots are making them feel strange, you may want to pay attention.

Doctors say there's a potentially dangerous condition out there that you probably don't know about -- yet it affects thousands of children every year.

One of those kids is 9-year-old Ryan Blattmann from Orlando. Anytime he takes a bite of an apple or peace or strawberry, he feels a tingling in his mouth.

"Feels like itching," says Ryan. "I feel like it's up top of my mouth."

Even his mom, Colleen, admits that she wasn't sure, at first, if this was a lie or something to worry about.

"It was a little crazy," says Colleen Blattmann. "I didn't know what to think."

Turns out -- Ryan was telling the truth, and suffers from what's called Oral Allergy Syndrome or Pollen Food Allergy Syndrome.

"All the parents are always stunned and surprised because this is new to them," says Dr. Jose Arias, an allergist in Orlando.

He says he sees the biggest spike in cases now, during the summer. The condition is triggered by raw fruits, vegetables, and nuts, which all have the same proteins as pollen.

"The body gets confused when you eat a piece of fruit, it thinks you're eating a piece of grass, a piece of tree, a piece of weed," says Dr. Arias. "Because you really are more allergic to the grasses, the trees, and the weeds than you are to the actual fruit."

So, what do you look for?

Within seconds of taking your first bite, you'll notice a tingling in your mouth, swelling of your lips and tongue, even tightness in your throat.

Dr. Arias says that anyone can have Oral Allergy Syndrome, especially children, because fruits and veggies are a big part of their diet.

"The more you eat fruit, the more likely you are to become allergic to it," says Dr. Arias. "You're giving it to them, and at the same time you're creating this problem without knowing."

So, as a parent, how can you make sure your kids are getting the nutrients they need?

Dr. Arias recommends peeling fruits and vegetables first, or cooking them, which breaks down those harmful proteins.

"You won't have it in apple sauce, you will not have it in apple pie, peach cobbler, any juice," says Dr. Arias.

Colleen Blattmann makes all those things for her son, along with smoothies, which don't give Ryan any problems.

"I would him to be able to try all fruits and stuff," says Blattmann. "We just try to work around it and hopefully hope for the best in the future."

Both Blattmann and Dr. Arias agree that if your child complains of a tingling in their mouth, that's the first warning sign, and you should take them to an allergist right away.