TELEVISION VIEWING AS A CAUSE OF INCREASING OBESITY AMONG CHILDREN INTHE UNITED-STATES, 1986-1990

Background and Methods: The prevalence of obesity among children and a dolescents has increased, and television viewing has been suggested as a cause. We examined the relation between hours of television viewed and the prevalence of overweight in 1990, and the incidence and remiss ion of overweight from 1986 to 1990 in a nationally representative coh ort of 746 youths aged 10 to 15 years in 1990 whose mothers were 25 to 32 years old. Overweight was defined as a body mass index higher than the 85th percentile for age and gender. Results: We observed a strong dose-response relationship between the prevalence of overweight in 19 90 and hours of television viewed. The odds of being overweight were 4 .6 (95% confidence interval, 2.2 to 9.6) times greater for youth watch ing more than 5 hours of television per day compared with those watchi ng for 0 to 2 hours. When adjustments were made for previous overweigh t (in 1986), baseline maternal overweight, socioeconomic status, house hold structure, ethnicity, and maternal and child aptitude test scores , results were similar (odds ratio, 5.3; 95% confidence interval, 2.3 to 12.1). We also found significant relations between television viewi ng and increased incidence and decreased remission of overweight durin g this 4-year period, adjusted for baseline covariates. The adjusted o dds of incidence were 8.3 (95% confidence interval, 2.6 to 26.5) times greater for youth watching more than 5 hours of television per day co mpared with those watching for 0 to 2 hours. Estimates of attributable risk indicate that more 60% of overweight incidence in this populatio n can be linked to excess television viewing time. Conclusion: Televis ion viewing affects overweight among youth, and reductions in viewing time could help prevent this increasingly common chronic health condit ion.