About five percent of middle and high school students have used anabolic steroids to put on muscle, according to a new study from Minnesota.

In addition to steroid use, more than one-third of boys and one-fifth of girls in the study said they had used protein powder or shakes to gain muscle mass, and between five and 10 percent used non-steroid muscle-enhancing substances, such as creatine.

Researchers said a more muscular body ideal in the media may be one factor driving teens to do anything possible to get toned, as well as pressure to perform in sports.

“Really the pressure to start using (steroids) is in high school,” said Dr. Linn Goldberg, from Oregon Health & Science University in Portland.

“You get the influence of older teens in high school, so when you’re a 14-year-old that comes in, you have 17-year-olds who are the seniors, and they can have great influence as you progress into the next stage of your athletic career.”

The new data came from close to 2,800 kids and teens at 20 different middle and high schools in the Minneapolis/St. Paul area. During the 2009-2010 school year, those students completed a survey on food and weight-related behaviors, including activities tied to muscle gain.

The majority of kids surveyed were poor or middle-class.

Almost all of them had engaged in at least one muscle-building activity in the past year, most often working out more to get stronger. But up to one-third of kids and teens used what the researchers deemed to be unhealthy means to gain muscle mass, including taking steroids and other muscle-building substances or overdoing it on protein shakes, dieting and weight-lifting.