NEW YORK (Reuters) - Violence depicted on television, in films and video games raises the risk of aggressive behavior in adults and young viewers and poses a serious threat to public health, according to a new study.

After reviewing more than 50 years of research on the impact of violence in the media, L. Rowell Huesmann, of the University of Michigan, and his colleague Brad Bushman concluded that only smoking posed a greater danger.

"Exposure to violent electronic media has a larger effect than all but one other well known threat to public health. The only effect slightly larger than the effect of media violence on aggression is that of cigarette smoking on lung cancer," he said in a statement.

Smoking, a leading cause of preventable death, is linked to lung cancer and other illnesses.

Huesmann said children spend an average of three hours watching television each day and more than 60 percent of TV programs contain some violence, including 40 percent showing extreme violence.

"Children are also spending an increasingly large amount of time playing video games, most of which contain violence. Video game units are now present in 83 percent of homes with children," he added.

The findings, which are reported in the Journal of Adolescent Health, support earlier research which showed that children who watch violent television shows and who identify with the characters and believe they are real are more likely to be aggressive as adults.

The results were true for both men and women.

"The research clearly shows that exposure to virtual violence increases the risk that both children and adults will behave aggressively," said Huesmann, adding it could have a particularly detrimental effect on the well-being of youngsters.

Although not every child exposed to violence in the media will become aggressive, he said it does not diminish the need for greater control on the part of parents and society of what children are exposed to in films, video games and television programs.

(Reporting by Patricia Reaney,Editing by Belinda Goldsmith)
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