We all know too much screen time is a bad thing for children. Now there's another reason to turn off the TV.
Canadian researchers are reporting in a new study that children who watch a lot of TV are more likely to have a larger waist circumference and be less likely to participate in sports.
Specifically, the study, published in the International Journal of Behavioral Nutrition and Physical Activity, found each hour of TV watched by children from ages 2 to 4 contributed to their waist size by the end of Grade 4.
By the time children in the study were 4.5 years old, their waist size increased by about half a millimetre for every additional hour of TV they were watching compared with when they were 2.5.
"The bottom line is that watching too much television – beyond the recommended amounts – is not good," Linda Pagani of the University of Montreal, senior author of the study, said in a press release.
Recommendations published last year by the Canadian Society for Exercise Physiology suggested that children and teens spend no more than two hours a day sitting, including while watching TV, outside of school hours. The American Academy of Pediatrics says children should not watch more than two hours of TV a day. Those under age 2 should not watch any TV, the organization says.
The new study was conducted with 1,314 children from the Quebec Longitudinal Study of Child Development. Researchers asked parents how many hours of TV the kids watched.
In addition to having slightly larger waist sizes, children who watched the most TV also had decreased athletic ability. Researchers found that each hour of TV children watch reduced the distance they could jump by one-third of a centimetre.
The distance is short, and the difference in waist size for children who watch the most TV may seem small. But over the course of many years, those changes could start to have a significant impact, researchers said.
"These findings support clinical suspicions that more screen time in general contributes to the rise in excess weight in our population, thus providing essential clues for effective approaches to its eradication," Dr. Pagani said.
How much TV do your kids watch each day? Are you concerned about the impact on their health?