Did you know that the average American adult watches almost 5 hours of television per day? In the December 2009 issue of Archives of Internal Medicine, scientists from the University of Vermont, Burlington report on the effects of television reduction on energy intake, energy expenditure, energy balance, body mass index, and sleep in overweight and obese adults.

The scientists performed a randomized controlled trial of 36 overweight and obese adults who reported a minimum of 3 hours per day of television viewing. From January through July 2008, these adults were randomized to either reducing television viewing by 50 percent or making no changes in their amount of television viewing. In the intervention group, television viewing was regulated by an electronic lock-out system. At the end of the follow-up period, both groups had reduced their energy intake, but this result was not statistically significant. The group that reduced their television viewing significantly increased their energy expenditure and achieved a negative energy balance. In addition, those adults who watched less television showed a greater reduction in body mass index.

Based on these findings, it does seem that watching less television has positive effects on energy expenditure and body mass index. It is not clear what the study participants did in the time freed by less television watching, so the reason for these positive effects remains undefined.

Source:

Arch Intern Med 2009;169(22):2109-2115.