About 14 percent of Philadelphia's high school students are considered overweight, and while a myriad of research has been published on what schools, communities and parents can do to help curb these rates, very little information exists on what the teens themselves are doing to lose weight.

Research led by public health doctoral candidate Clare Lenhart has found that while most obese teens in Philadelphia report wanting to lose weight, their actions are more of a hindrance than a help.

In an analysis of findings from the Philadelphia Youth Risk Behavioral Survey, Lenhart and colleagues organized data from nearly 44,000 adolescents into different types of health behaviors, such as: recent smoking; amount of weekly physical activity; daily soda consumption; and hours per day playing video games.

While most of the obese teens reported trying to lose weight (about 75 percent), this group was also more likely to report smoking. In addition, females trying to lose weight were more likely to report participating in 60 minutes or more of physical activity per day; however, data showed that these females were also prone to consume soda on a daily basis - regular, not diet. Males who were trying to lose weight were more likely to report having no days of physical activity, and also reported playing more than three hours of video games per day.

"From a health education standpoint, finding out that three-quarters of students who are obese want to lose weight is exactly what we want," said Lenhart. "But the behavior they're engaging in is puzzling; it's counterproductive to what they're trying to do."

While the researchers aren't sure whether teens realize this behavior is counterproductive, Lenhart suggests there could be a lack of information on the teens' part. "For example, among the girls who are exercising, they may not realize that one soda could undo that 30-minute walk they just took."

She's encouraged that so many teens appear to be motivated to lose weight, and says that a more intensive line of questioning from health care providers could help.

"If a child is going to their pediatrician, and he asks them if they're losing weight, an appropriate follow up question might be, 'How are you doing that?'" said Lenhart. "It could help guide those teens to more productive weight loss activities."

This research was presented at the annual meeting of the American Public Health Association. Other authors on this study are Dawn Eichen of the Department of Psychology and Judith Gold of the Department of Public Health; and Brian Daly of Drexel University's Department of Psychology. Funding for this study was provided by a CDC ARREST grant to the School District of Philadelphia.