The role of television in childhood obesity

Childhood obesity has more than tripled in the past 30 years. Although causes are multi-factorial, television viewing has been consistently associated cross-sectionally, longitudinally, and in intervention studies to childhood obesity. The mediators explaining these relationships include increased calorie intake and poorer dietary quality, and to a lesser extent, reduced physical activity. Sophisticated marketing of high fat, high sugar, high calorie foods and beverages is increasingly being targeted to children and adolescents. These advertisements have been shown to affect children's preferences, requests, and short-term consumption of foods and beverages. Foods eaten as snacks or as meals while viewing television tend to be higher in fat and calories, and are less likely to include fruits, vegetables or dairy products, which are also the foods least likely to be advertised. Surveys find that television sets in children's bedrooms have been increasing, so that now some 50% to 70% of youth have a bedroom television set. They view more hours of television than those without a television in the bedroom and their viewing is underestimated and often not monitored by parents. Classroom curricula and focused parental efforts to reduce and limit children's television viewing can lead to decreased viewing, which in some cases has been associated with decreased obesity. Efforts to separate snacking or eating while watching television may also be beneficial. Public awareness efforts, such as TV (Screen) Turn-off Week are gaining momentum, as are local school, childcare and after-school policies to limit children's television viewing and use of other screen media. Pediatricians can play a role individually in educating their patients and parents or collectively in raising awareness and/or advocating for local, state or federal policies to limit children's exposure to television and to restrict marketing and advertising of high-fat, high sugar, high calorie foods to children and adolescents.