TORONTO -- Children who spend too much time glued to the TV or computer are at risk of obesity and delayed development, but researchers say finding ways to help busy parents limit kids' screen time is no easy task.
"Making lasting behavioural changes, like cutting back on screen time, can be a challenge for people of all ages," says Dr. Catherine Birken, a pediatrician and researcher at Toronto's Hospital for Sick Children.
Birken headed a study that tested the effectiveness of a physician-based intervention, in which parents were counselled about ways to reduce TV time as part of their three-year-old child's visit to the doctor.
In the study of 160 families, published Monday in the journal Pediatrics, parents were randomly selected so half received the 10-minute counselling session, while the remaining half were given a talk about Internet safety for youngsters.
The counselling session in the first group gave parents information about the adverse effects for children of too much TV-watching. It offered strategies to reduce screen time, such as removing the TV from the child's bedroom, eating meals away from the television and alternative activities for their preschooler.
When the outcomes were measured one year later, researchers hoped the doctor-delivered intervention might have cut the overall amount of TV a child was watching. They also wanted to see if counselling had led to a lower body mass index, or BMI, in the children and fewer meals and snacks eaten in front of the television.
"We were not successful in reducing screen time overall, and we were not successful in reducing BMI," said Birken.
"But we did find an impact on reducing the number of meals in front of the TV, by about two meals per week," she said.
While the amount is not huge -- on average, kids eat about two meals per day, or 14 per week, while watching the tube -- Birken said the reduction shows counselling parents has some positive effect, at least when it comes to preschoolers.
"I think it's important," she said.
"There are other studies in older children that show that while watching TV, children are not good at reading their own satiety cues. They tend to eat more and the food they tend to eat more of is unhealthy food, and food that's highly advertised on TV.
"So I think one of the strong mediators of the relationship between screen time and obesity is likely food being eaten while you're watching the screen."
Dr. Dimitri Christakis, director of the Center for Child Health, Behavior and Development at Seattle Children's Hospital, said he is not surprised by the results of the Sick Kids study, which he called well-designed.
"We've done interventions to try to reduce TV viewing that are considerably more intensive and achieved an effect size of about 20 minutes. They watch 20 minutes less," he said from Seattle.
Christakis, who has been involved in numerous studies related to cutting kids' screen time, said those interventions included sending newsletters and making phone calls to parents aimed at helping them limit children's TV exposure.
But with the average preschooler in the U.S. watching more than four hours of TV a day, reducing the amount by 20 minutes is trivial, he conceded.
"The reasons parents have their children watch as much TV as they do are multiple and complex. The truth is that most parents when asked already feel guilty about how much TV their children watch, but they still let them watch as much as they do.
"So reducing it is a challenge."
Many people believe TV-watching leads to obesity because it's a sedentary activity. But so are reading or playing board games, and those activities aren't seen as unhealthy, he pointed out.
"The reality is that children watch TV because they're sedentary; they're not sedentary because they watch TV. Children are kept inside too much and once they're inside the house, whatever they do does not expend an appreciable amount of calories."
Christakis said TV viewing is linked to obesity because kids are exposed to ads that promote unhealthy foods and because they tend to eat too much while glued to the screen.
"So the reduction in meals in front of the television could potentially be significant."
-- The Canadian Press