And it's not just that many teens are couch potatoes, the academy argues in the July issue of Pediatrics: TV advertising drives sales of junk food, children and teens tend to snack while watching TV or online, and late-night use may interfere with sleep.
"We've created a perfect storm" of conditions that predispose young people to obesity, said lead author Victor Strasburger, MD, of the University of New Mexico in Albuquerque, N.M.
"We couldn't do a worse job as a society if we tried," he told MedPage Today.
The academy's policy statement calls obesity "a clear and present danger" to children and teens and says that evidence linking excessive TV with obesity is now "persuasive," although the role of other media remain unclear.
Currently, the researchers found, U.S. children and teens spend an average of seven hours a day using various forms of media -- more time than they spend doing anything except sleeping.
Physicians and other health professionals can play a role, the academy said, by encouraging parents to monitor children's TV viewing, teach them about good nutrition, and discuss the impact of food advertising.
They should also continue to urge parents to limit non-educational screen time to no more than two hours a day, and avoid putting TV sets and internet connections in children's bedrooms, the statement suggests.
"Docs need to be asking at least two media questions at every well-child, well-baby, well-adolescent visit," Strasburger said. "How much entertainment screen time does the child or teenager spend per day and is there a TV set or internet connection in the bedroom?"
Among other things, the policy statement urges:
- Bans on advertising of unhealthy food to children and teens
- Restrictions on interactive food advertising to children via digital media
- Support for research into the health and psychosocial effects of heavy media use in children
- More media resources for children that encourage them to choose healthy foods
- Parental limits on screen time
Strasburger said the policy statement is not an example of "nannyism" run wild.
Among other signs of the times, he noted that 75% of American youngsters now have a TV in their bedroom. "The evidence is clear and convincing that that puts children at risk for obesity," he said.
Among the content they see on those screens, he noted, are thousands of ads every year for fast and junk food. "Food marketers spend $10 billion a year targeting children and teenagers," he said. "There's a significant relationship [with obesity] and it has to stop."
Indeed, a study appearing in the same issue of Pediatrics found that food commercials touting fast and junk foods influenced children's food choices – skewing them toward high-fat and high-carbohydrate items, according to Emma Boyland, PhD, of the University of Liverpool in England, and colleagues.
And the effect was greater for children who watched more than 21 hours of TV a week, they reported, compared with those who watched less.
Interestingly, those children also had a significantly greater body mass index (at P<0.05) than those who were less frequent viewers, Boyland and colleagues reported.
The findings came from an experiment in which 281 children, ages six to 13, were twice shown an episode of a popular cartoon, separated by two weeks.
In each case, the cartoon was preceded by five minutes of commercials – for toys at one showing and for food (mainly snacks and fast food) at the other, the researchers reported.
After each showing the children were given lists of various food items, both branded and unbranded, and asked what they'd like to eat. They were more likely to pick unhealthy foods after they had watched the food commercials, the researchers found.
The policy statement had no external support. Strasburger said he had no conflicts.
The authors of the study of commercials did not report any external support. They said they had no conflicts.
- Reviewed by Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
PediatricsSource Reference: Strasburger VC, et al "Policy statement -- Children, adolescents, obesity, and the media" Pediatrics 2011; 128: 201–208.
PediatricsSource Reference: Boyland EJ, et al "Food commercials increase preference for energy-dense foods, particularly in children who watch more television" Pediatrics 2011; 128: e93–e100.