Adults and children who watch more television have less healthy diets, finds a new study in the American Journal of Preventive Medicine. For every age and gender studied, people who watched no more than an hour of TV a day reported healthier diets compared to those who watched four hours or more.

The findings provide evidence to support more extensive research into how TV watching may affect what people eat, said study lead author Susan B. Sisson, an assistant professor who studies nutrition at the University of Oklahoma. "The next step is to see if we can affect some positive change and design interventions to address TV viewing. If we address TV viewing, does improve?"

Previous research has found that people who watch more TV are more likely to be overweight or obese, but the new study is one of the first to look at , Sisson said.

The researchers looked at results from 2003-2006 federal surveys that asked adults and children about TV viewing and diets. The subjects included 8,222 , 3,343 , 1,749 kids aged 6-11 and 1,423 preschoolers. The study used an overall index to measure participant’s diet quality. As a result, no specifics were obtained about what foods people were eating.

Still, some studies have shown that kids lose weight if they watch less TV, possibly because they are not sitting as much, not eating as many snacks while watching TV or not seeing commercials for fast-food restaurants and unhealthy foods, Sisson said.

Victor Strasburger, M.D., chief of the division of adolescent medicine at the University of New Mexico School of Medicine, praised the new study and said that although kids are immersed in a media environment, parents do have responsibilities. "Ignore the research at your own, and your kids', peril. No, media use is not the leading cause of obesity; but it contributes significantly. Parents need to avoid screen time for babies under 2 years old and limit total entertainment screen time--TV, movies, videos, video games--to less than 2 hours per day, per the American Academy of Pediatrics recommendation."

More information: Sisson S, et al. (2012). Television-Viewing Time and Dietary Quality Among U.S. Children and Adults. American Journal of Preventive Medicine, In Press.

Journal information: American Journal of Preventive Medicine