A new study by the University of Minnesota finds that more teens are using diet drugs. The research finds that 14-percent of high-school aged girls use the pills.

That's nearly double the rate of just five years ago.

The study also reveals that 63-percent exhibit unhealthy weight control behaviors.

Kenna Shearman says, "Almost every girl that I am friends with or know has a problem with the way they look."

That's why Kenna likes shopping at Be Yourself.

"On the tag there is a color dot and it basically represent a size," she says. "I love that there are no sizes."

Shearman says sizes can make teenage girls insecure.

"Everyone just feels the pressure from media that you have to be skinny and tall so girls resort to stupid things."

One of those things can be diet pills.

Dr. Martin Harrington says, "I've been working with eating disorder patient for over 10 years and, yes, the use of diet pills has increased over the years."

Dr. Harrington says over-the-counter diet pills are designed for adults and can often be harmful to a teenage body.

"They can be very dangerous and even lethal in overdose amounts," he says.

He also says that he has found that most teenagers who use diet pills, overdose.

"They take a couple and if that works well they think four works better and I have people taking as many as eight or 10 at a time."

Dr. Harrington says that from what he has seen the use of diet pills usually accompanies other eating disorders.

He says, "It's pretty rare that I see someone just using diet pills to control their weight. Often they are doing some restrictive activity and excessive exercise."

Kenna Shearman says, "Personally, I would never do them."

But she says she has a lot of friends who do.

"They resort to diet pills, become addicted and take a lot more than they should."

One clue that parents can look for is a child's spending. Diet pills are not cheap.

For more information on the University of Minnesota study, click here.