Television viewing habits associated with obesity risk factors: a survey of Melbourne schoolchildren

Objectives: To examine whether children's television viewing may be a useful indicator of risk of obesity-promoting versus healthy eating behaviours, low-level physical activity (PA) and overweight or obesity among children of primary school entry and exit ages. Design: Cross-sectional study, stratified by area-level socioeconomic status. Participants and setting: 1560 children (613 aged 5-6 years [50% boys], and 947 aged 10-12 years [46% boys]) from 24 primary schools in Melbourne, Australia, randomly selected proportionate to school size between 1 November 2002 and 30 December 2003. Main outcome measures: Parents' reports of the time their child spends watching television, their participation in organised physical activities (PA), and their food intake; each child's measured height and weight and their PA levels as assessed by accelerometry for one week. Results: After adjusting for the age and sex of child, the parents' level of education, clustering by school, and all other health behaviour variables, children who watched television for > 2 h/day were significantly more likely than children who watched television for <= 2 h/day to: to have one or more serves/day of high energy drinks (adjusted odds ratio [AOR], 2.31; 95% Cl, 1.61-3.32), and to have one or more serves/day of savoury snacks (AOR, 1.50; 95% Cl, 1.04-2.17). They were also less likely to have two or more serves/day of fruit (AOR, 0.58; 95% Cl, 0.46-0.74), or to participate in any organised PA (AOR, 0,52; 95% Cl, 0.34-0.80). Conclusions: Health practitioners in the primary care setting may find that asking whether a child watches television for more than 2 hours daily can be a useful indicator of a child's risk of poor diet and low physical activity level.