The most common approach to treat obesity is lifestyle intervention, including changes in dietary intake and physical activity. While moderate weight loss can often be achieved through dieting, most people regain their lost weight over time.[iv]
Appropriate pharmacotherapy can help patients achieve about a five to ten percent weight loss in one year. However, if effective, pharmacotherapy must be continued, and rapid weight regain will occur when drug therapy is stopped. Moreover, many patients will begin to regain weight after one year of drug therapy despite continued treatment. Few drugs are currently approved for obesity therapy and only one (orlistat which blocks the absorption of fat) is approved for long-term use in obese patients in the United States.
[iv] Wadden TA, Foster GD, Letizia KA. One-year behavioral treatment of obesity: comparison of moderate and severe caloric restriction and the
effects of weight maintenance therapy. J Consult Clin Psychol 1994;62:165-171.
[v] Goldstein DJ. Beneficial health effects of modest weight loss. Int J Obes Relat Metab Disord 1992;16:379-415.