KO! Mortal Kombat, circa '93

A study suggests that the only thing more harmful than violence in the media is smoking.

L. Rowell Huesmann and his colleagues at the University of Michigan reviewed over 50 years of research on the impact of violence in the media, reports Reuters.

Huesmann finds 60 percent of TV programs contain some violence, and 40 percent contain extreme violence.

Long a source of extreme violence, video games were also pointed out. 83 percent of homes with children have a gaming console.

Children also spend an average of three hours a day watching TV, making them more likely than adults to act out violence when they identify with the actions of fictional characters.

However, the study did not rule out adults, observing both men and women are equally prone to acting out violence they see in the media.