Addition by Subtraction

Investigators from the University of Vermont reported in the most recent issue of Archives of Internal Medicine that limiting TV viewing by 50% in adults resulted in significantly increased levels of physical activity and energy expenditure. The overweight and obese volunteers were monitored over a 6 week period. During the first 3 weeks all volunteers were monitored for baseline TV viewing. During the second 3 week period half of the participants were locked-out of their TVs once they reached 50% of their usual viewing until the beginning of the next week. The volunteers were not instructed to do anything in particular to replace television viewing. Nevertheless, the intervention resulted in an increased calorie expenditure of 119 calories per day. There was no change in energy expenditure. While this does not seem like much of a calorie differential, if maintained volunteers would lose an average of 12 lbs of fat in one year, and 60 lbs in 5 years.