FRIDAY, Jan. 30 (HealthDay News) - Teens who watch TV more than five hours a day are prone to become fast-food junkies as adults, a new study suggests.
The connection? Too much time spent watching ads for fast food restaurants, snacks and other unhealthy food choices, University of Minnesota researchers say.
"Television watching impacts diet choices adolescents make five years later," said lead researcher Daheia Barr-Anderson, an assistant professor of kinesiology.
Barr-Anderson also speculates that eating while watching TV makes children more likely to consume the foods they see advertised.
The report was published in the Jan. 30 online edition of the International Journal of Behavioral Nutrition and Physical Activity.
For the study, Barr-Anderson and colleagues collected data on 564 middle school students and 1,366 high school students. The team examined survey data on the number of hours the students watched TV each day and what they ate five years later as young adults.
Five years out, high-school students who had watched more than five hours of TV a day and were now young adults ate less fruit, vegetables, whole grains and calcium-rich foods. Instead, they ate more snack foods, fried foods, fast food, sugar-sweetened beverages and foods containing trans-fats.
To get children to eat healthier, parents need to play a more active role -- limiting TV watching and instilling healthful eating habits, Barr-Anderson said.
"Parents need to adhere to the American Academy of Pediatrics' recommendation that children watch less than two hours of quality television per day," she said. "Parents need to restrict what their kids are eating and try and provide a better example for their kids, making sure they are getting the nutrients and proper food that they need as opposed to the high-fatty foods, high-sugar foods, low-nutrient-dense foods."
Frederick J. Zimmerman, an assistant professor at the Child Health Institute of the University of Washington, said the study raises important issues.
"This research tugs not so gently at the wool in front of all of our eyes -- revealing that heavy TV viewing, especially of food advertising -- makes a difference to our children's diets," he said.
Anyone familiar with the research on television viewing, advertising, and diet will not be surprised by these results, Zimmerman added. "This research suggests that heavy TV-viewing adolescents consume about 200 more calories per day than those who watch a moderate amount of TV. That is a lot of calories by anyone's count," he said.
Another expert agreed that, in the end, parents are the key to change.
"This study is a clear wake-up call that entertainment media matter when it comes to health," said Kimberly M. Thompson, an associate professor of risk analysis and decision science at the Harvard School of Public Health. "Given the current obesity and overweight crisis in America, this study provides clear evidence that kids and parents should make a point of reducing sedentary time spent in front of a TV screen," she said.
It's not clear from the study if TV ads for junk food, "couch potato'" lifestyles, or both, are leading to bad diets, Thompson said. But regardless of the cause, parents need to take action.
"For those looking to nudge their families in the right direction, implement a rule in your home of no eating while the TV is on. Or if that's too tough, then insist that only fruits and vegetables and water get consumed while viewing TV," she said. "You could also require that for every hour of TV viewed, each member of the family needs to engage in at least 20 minutes of vigorous exercise."
For more about a healthy diet, visit the U.S. Department of Agriculture.
SOURCES: Daheia Barr-Anderson, Ph.D., assistant professor, kinesiology, University of Minnesota, Minneapolis; Frederick J. Zimmerman, Ph.D., assistant professor, Child Health Institute, University of Washington, Seattle; Kimberly M. Thompson, Sc.D., associate professor, risk analysis and decision science, Harvard School of Public Health, Boston; Jan. 30, 2009, International Journal of Behavioral Nutrition and Physical Activity