OBJECTIVE Numerous reports have suggested that cycles of weight loss and regain (i.e., weight cycling) are associated with adverse health consequences, a concern that may lead some obese individuals to forgo weight control efforts. The present study examined whether weight cycling was associated with a reduction in resting energy expenditure (REE) and with increases in both total and upper body fat. METHODS REE, body composition, and body fat distribution were measured before and after weight loss, and following full weight regain, in 12 women who before treatment had a mean (+/- SEM) age of 38.8 +/- 3.4 years and weight of 98.0 +/- 3.2 kg. RESULTS At the end of treatment, patients lost 18.9 +/- 2.6 kg which was comprised of significant decreases in body fat and fat-free mass of 15.2 +/- 2.2 and 3.7 +/- 0.8 kg, respectively (both ps < .001). REE also fell during this time from 1,631 +/- 82 to 1,501 +/- 51 kcal/d (p < .03). All of these measures, however, returned to their baseline values when patients regained their lost weight. Body fat distribution was unchanged throughout the study. CONCLUSIONS These results do not support claims that weight cycling adversely affects REE, body composition, or body fat distribution.