MONDAY, Oct. 11, 2010 (HealthDay News) -- Pre-teens who spent more than two hours a day in front of the TV or computer were at greater risk of having psychological problems than youngsters averaging less screen time, even if the kids also tended to be physically active, new research finds.
The study, published online Oct. 11 and in the November print issue of Pediatrics, found that the risk of psychological difficulties increased by about 60 percent when kids between 10 and 11 years old spent more than two hours daily watching TV or playing on the computer.
"Children who spent more than two hours per day watching television or using a computer were at increased risk of high levels of psychological difficulties," regardless of how physically active they were, study lead author Angie Page, from the Centre for Exercise, Nutrition and Health Sciences at the University of Bristol in England, and colleagues found.
Still, the experts stressed that the study can't discern whether media exposure causes psychological woes in kids, or whether troubled children simply prefer spending time in front of computers or the TV.
Previous studies have linked excessive TV viewing with childhood obesity, and both TV and computer use have been associated with psychological problems and an increase in sedentary time, according to background information in the study.
Page said the researchers decided to undertake this study because while it's known that physical activity is good for both physical and mental health in children, it wasn't clear if high physical activity levels could compensate for the adverse effects associated with high TV and computer use.
The study included more than 1,000 children between the ages of 10 and 11. The youngsters were recruited from 23 schools in Bristol, and all of the children self-reported their TV and computer use.
The researchers had all of the children complete a Strengths and Difficulties questionnaire, which is designed to measure psychological difficulties, such as hyperactivity, inattention, social problems and conduct issues.
"The difficulties measured by this questionnaire are not subtle things," noted Dr. Alan Mendelsohn, an associate professor of pediatrics at the New York University School of Medicine in New York City. "These are big-deal issues, like hyperactivity, difficulty with peers and friends, poor conduct and antisocial kinds of behaviors."
Overall, most children reported spending between an hour or two a day on TV and computer use for entertainment. On average, boys were moderately to vigorously active for an average of 83 minutes per day, versus 63 minutes for girls, according to the study.
The study found that children who spent more than two hours a day watching television or using a computer were more likely to have reported psychological difficulties than children who spent less time in front an electronic screen. Kids who watched more than two hours of TV a day had a 61 percent increased risk of psychological difficulties, while those who spent more than two hours on a computer were 59 percent more likely to have psychological difficulties.
When children weren't very active throughout the day, the risk of psychological difficulties went up even more. The risk of psychological problems for sedentary children who watched more than two hours of TV was 70 percent, and for those who spent more than two hours on the computer, the odds were increased 81 percent.
Surprisingly, being highly physically active didn't offer much protection against psychological difficulties if children already clocked more than two hours of screen time each day. The risk of psychological difficulties was still increased by about 50 percent for the highly active group when they spent more than two hours watching TV or using the computer, according to the study.
"For parents, the key take-away is that TV and computer use may interfere with children's emotional well-being," said Mendelsohn.
However, he noted that the study wasn't designed to tease out whether there is a cause-and-effect relationship between screen time and psychological problems, or if troubled youngsters are simply more likely to spend more time with TV and computers.
"We don't know if it's the psychological problems that cause kids to become withdrawn, or if there's something harmful to TV and computer use," said Carolyn Landis, a licensed clinical psychologist and an associated professor of pediatrics at Rainbow Babies and Children's Hospital in Cleveland.
"But, if your child wants to spend more than two hours a day -- not including homework -- on the computer, I would consider that a potential red flag that something might be wrong. Kids might be depressed and are saving themselves from face-to-face interactions by using the computer," said Landis.
"It's also important to know that you can have a really active, athletic child, but it's still not OK for them to spend three hours a day on the computer," she said.
Read more about the benefits of limiting screen time from the American Academy of Pediatrics.