Although dieting has a modest short-term effect in the treatment of obesity, the long-term benefit has yet to be demonstrated.1 This is not surprising because caloric intake has not increased during the last 100 years. Rather, there has been a sharp drop in caloric expenditure secondary to changes at the workplace and in the home.2 Surveys of people who have sustained significant weight loss for more than 5 years demonstrate that a significant increase in energy expenditure is necessary.3 In this issue of the Archives, Jakicic et al report 2-year results from a study designed to determine the duration and intensity of physical activity necessary to maintain weight loss. They conclude that 2000 kcal/wk of exercise is needed to sustain weight loss.
Thompson WG, Levine JA. Effect of Exercise on 24-Month Weight Loss Maintenance in Overweight Women—Invited Commentary. Arch Intern Med. 2008;168(14):1559–1560. doi:10.1001/archinte.168.14.1559