Study Quantifies Effect of TV Viewing on Adolescent BMILast Updated: August 31, 2012. For adolescents, a decrease in television viewing time correlates with a lower body mass index z score, according to a study published in the September/October issue of the Journal of Nutrition Education and Behavior.
FRIDAY, Aug. 31 (HealthDay News) -- For adolescents, a decrease in television (TV) viewing time correlates with a lower body mass index (BMI) z score, according to a study published in the September/October issue of the Journal of Nutrition Education and Behavior.
Simone A. French, Ph.D., from the University of Minnesota in Minneapolis, and colleagues conducted a randomized intervention trial in which 153 adults and 72 adolescents from the same households were assigned to a home-based obesity prevention intervention or to no intervention (control group) for a one-year period. TV viewing hours, diet, and physical activity were self-reported and their correlations with body weight change were examined.
The researchers found that, among adolescents, there was a significant prospective association between reductions in TV viewing hours and lower BMI z score at one year (decreased TV hours: BMI z score mean, 0.65; no change or increase in TV hours: BMI z score, 0.92). For adults, no significant prospective associations were observed.
"The results of the present study suggest that TV reduction may be an effective strategy to prevent excess weight gain among adolescents," the authors write. "Further research is needed to better understand the mechanisms by which TV reduction achieves its protective effect on BMI among youth."