TV and Computer Limits Make Kids Slimmer
The Wall Street Journal
March 3, 2008
Blocking your kids’ access to TV and the computer could
help them shed weight, an experiment with 70 overweight
The results of the study, published in the current issue of Archives of Pediatrics & Adolescent Medicine, involved children aged 4 to 7 years whose body mass index (BMI) was at the 75th percentile or higher for their age and gender. All of them regularly watched television or played computer games for at least 14 hours a week at home. That doesn’t even sound like a lot compared with some of the habits of kids we know.
Anyway, about half of the kids in the study had limits on their TV and computer time enforced with an electronic gadget that required a special code for access. By the end of the study, the kids with the special blocker in their homes cut their use by about 17.5 hours a week, compared with a decrease of about 5.2 hours a week in the other group. Over two years of observation, the BMI fell in the group with the blocker. The control group showed an increase in BMI followed by a gradual decrease, but ultimately it didn’t fall as far as the kids in the blocker group. Interestingly, there was no significant difference in the amount of physical activity between the groups.
Steven Gortmaker, a health-sociology professor who researches obesity at the Harvard School of Public Health, calculates that the kids who cut down their TV and computer time also trimmed 150 calories from their daily intake compared with the control group. That’s about one sugar-sweetened beverage a day, Gortmaker tells the Health Blog — and it’s a meaningful drop when it comes to childhood obesity. He suggest that the lower BMI for the restricted group may be due to less exposure to marketing of junk food.
The results of the study, Gortmaker says, are significant because it was a randomized trial that had “very precise control over screen time.” Much of the research around diet, physical activity and obesity is based on “observational” studies that aren’t considered as strong scientifically as a randomized trial, he says.
Gortmaker seemed most taken with the device that was used to reduce the kids’ TV and computer use: the “TV Allowance” device. As he describes it in his commentary on the study, the device, which costs about $100, allows parents to give weekly allowances for electronics use. Each kid has his or her own code, and the device tracks usage so the kids don’t go past the allotted time. It works by controlling power to the TV or computer monitor.