Reuters: More than half of teenagers mention risky behaviors such as sex and drugs on their MySpace accounts, U.S. researchers said on Monday.

They said many young people who use social networking sites such as News Corp's MySpace do not realize how public they are and may be opening themselves to risks, but the sites may also offer a new way to identify and help troubled teens.

"We found the majority of teenagers who have a MySpace account are displaying risky behaviors in a public way that is accessible to a general audience," said Dr. Dimitri Christakis of Seattle Children's Research Institute, whose studies appear in the journal Archives of Pediatric & Adolescent Medicine.

In one of two studies, Christakis and Dr. Megan Moreno of the University of Wisconsin analyzed 500 randomly chosen MySpace profiles of 18-year-olds in 2007.

Overall, 54 percent of the publicly available accounts they checked contained information about high-risk behaviors: 41 percent mentioned substance abuse, 24 percent sexual behavior and 14 percent violence.

Christakis said many teens are unaware of how public and permanent Internet information can be, while parents often do not know what their kids are up to.

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