FRIDAY, Aug. 31, 2012 (HealthDay News) -- Reducing the amount of time that teens spend watching television may prevent them from putting on too much weight, researchers say.
In a new study, 153 adults and 72 adolescents in the same households were randomly assigned to receive either a one-year "TV allowance," which limited their total household viewing hours, or to continue with no TV restrictions. The participants' diet and physical activity levels were assessed, as well as television viewing hours, before and after the study period.
After one year, there was a clear association between the reduction in TV time and decreased weight gain among kids. However, limiting television viewing did not have a significant impact on weight gain in adults, the investigators found.
The findings suggest that television viewing is a risk factor for excess weight gain among adolescents, the University of Minnesota researchers said. They suggested that limiting kids' TV time is a way for parents to help their children maintain a healthy weight.
The study was published in the September/October issue of the Journal of Nutrition Education and Behavior.
"We tried to intervene on behaviors that are related to energy balance, such as television viewing, sugar-sweetened beverage intake, physical activity, and consumption of packaged convenience foods. Although the individual contribution of each of these behaviors to excess weight gain and obesity may be small, it is important to examine their possible role individually and together in promoting excess weight gain," principal investigator Simone French, director of the university's Obesity Prevention Center, said in a journal news release.
"Associations between these behaviors and risk for excess weight gain may differ among adults and adolescents because of their different physical and social developmental stages," French added.
According to U.S. National Health and Nutrition Examination Survey data from 2003-2006, about 31 percent of children and teens in the United States are overweight or obese.
While the study uncovered an association between limits on kids' TV time and reductions in excess weight gain, it did not prove a cause-and-effect relationship.
The Nemours Foundation has more about children's weight.