Children in kindergarten and first grade who spend just an hour a day in front of the television are more likely to be obese or at least overweight than those who watch less, a study has determined.
While previous studies have suggested risks of children being overweight go up if they spend a lot of time watching television, the latest research is the first to specifically examine the link between TV viewing and obesity among children as young as kindergarten age.
The researchers looked at data collected in an Early Childhood Longitudinal Survey of more than 11,000 children who had been in kindergarten in the 2011-2012 school term.
During the survey, parents were asked about lifestyle factors in the home that could affect a child's performance at school, including how many hours of television they watched on weekdays and weekends.
At the time of the survey, the weight and height of the children were measured. One year later, another round of measurements was made.
The study showed that the average U.S. kindergartner watched 3.3 hours of television daily; both kindergartners and first grade students who watched more than an hour a day had body mass indexes significantly higher than those who watched less than an hour, the researchers reported at a meeting of the Pediatric Academic Societies in San Diego.
The children watching an hour or more were 52 percent more likely to be classified as overweight, they said.
The findings held even after controlling for factors such as gender, race, ethnicity or socioeconomic level, they added.
A current recommendation by the American Academy of Pediatrics is that children and teens be limited to under two hours of television watching daily, but study author Mark D. DeBoer, a professor of pediatrics at the University of Virginia, says that is still likely too much.
"Given overwhelming evidence connecting the amount of time TV viewing and unhealthy weight, pediatricians and parents should attempt to restrict childhood TV viewing," he says. "Given the data presented in this study, the AAP may wish to lower its recommended TV viewing allowances."
The new finding comes on top of more than 30 years of research linking heavy television watching with obesity, all finding a positive correlation between weight and the number of hours spent on the living room sofa in front of the TV.
There have also been studies strongly suggesting children provided with a television set in their bedroom tend to be overweight when compared with children without a bedroom TV.