Decrease in Television Viewing Predicts Lower Body Mass Index at 1-Year Follow-Up in Adolescents, but Not Adults

ObjectiveTo examine associations between television viewing, sugar-sweetened beverage consumption, eating out, physical activity, and body weight change over 1 year.DesignSecondary data analysis from randomized intervention trial.SettingHouseholds in the community.ParticipantsAdults (n = 153) and adolescents (n = 72) from the same households.InterventionHouseholds were randomized to a home-based obesity prevention intervention or to a no-intervention control group for a 1-year period.Main Outcome MeasuresSelf-reported television viewing (TV) hours, diet, and physical activity. Body mass index (BMI) computed from measured weight and height (primary outcome measure).AnalysisMixed-model regression.ResultsAmong adolescents, a significant prospective association was observed between decreases in television viewing hours and lower BMI z score at 1-year follow-up (decreased TV hours: BMI z score mean = 0.65; no change or increase TV hours: BMI z score = 0.92; P < .02). No significant prospective associations were observed among adults.Conclusions and ImplicationsReducing television viewing may be an effective strategy to prevent excess weight gain among adolescents.