Kids and young adults who watch more than two hours of TV and video each day are twice as likely as those who watch less to suffer from attention problems, according to a study published in Pediatrics and reported by HealthDay News

For the study, Iowa State University researchers looked at the TV and video game habits of 1,300 children (third to fifth graders) over a 13-month period and 210 college students for a one-time evaluation. Researchers divided them into two groups: those who watched TV or played video games less than two hours a day (the recommended TV viewing time from the American Academy of Pediatrics) to those who logged more screen time.

Both children and parents reported how often kids watched TV and played video games. Elementary school teachers reported on all of the children’s attention-span problems. And college students self-reported.

Findings showed that participants who exceeded more than two hours of TV watching a day had double the risk of having greater than average attention problems. (The younger students spent almost four and one half hours watching TV or playing video games each day, and older students spent almost five hours doing the same.)

“ADHD [attention-deficit hyperactivity disorder] is 10 times more common today than it was 20 years ago,” said Dimitri Christakis, MD, a professor of Pediatrics at the University of Washington in Seattle. “And although it is clear that ADHD has a genetic basis, given that our genes have not changed appreciably in that timeframe, it is likely that there are environmental factors that are contributing to this rise.”

But the kind of video material kids and young adults watch is also important, said Christakis, explaining that fast-paced programs hiked the chances of developing attention problems.

Why is that? Because once the mind registers the hurried pace of TV shows and video games, real-life events happening at a slower tempo bore the brain, Christakis said.

Other researchers agreed with Christakis and suggested that the study should have included these variables.

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