The past, present, and future of behavioral obesity treatment.

Over the last century, hundreds of evaluations have been conducted to examine weight-management interventions related to diet, physical activity, and behavior therapy. These investigations have contributed to a growing body of knowledge that has consistently advanced the field of obesity treatment, while also revealing some persistent challenges. This narrative review summarizes key findings from randomized controlled trials conducted in adults that have combined diet, physical activity, and behavior therapy, an approach variously referred to as behavioral treatment, comprehensive lifestyle modification, or intensive lifestyle intervention. The review shows that current behavioral approaches induce average reductions in baseline body weight of 5 to 10% at 6 to 12 months. Such losses have proven effective in reducing the risk of type 2 diabetes in persons with impaired glucose tolerance and in improving other obesity-related complications. These benefits have also been associated with reductions in healthcare costs. Despite these advances, behavioral treatment is challenged by the need for larger losses to achieve optimal improvements in health, by difficulties associated with maintaining weight loss, and by barriers limiting access to treatment. New anti-obesity medications, when combined with behavioral obesity treatment, hold promise of addressing the first two issues.