Weight cycling: more questions than answers

Most men and women who attempt to lose weight will regain any weight that is lost. This cycle of weight loss and regain - referred to as weight cycling is a recurrent phenomenon for many patients. With the increased frequency of obesity and the increased prescriptions for weight-loss practices without an associated increase in the success of weight-loss maintenance, the concerns about weight cycling have grown. Recent literature has focused on the possible physiologic and psychologic hazards of weight cycling. Review of both human and animal studies indicates no conclusive evidence about harmful effects of weight cycling. Most studies show no adverse effects on metabolism. Some observational studies indicate an association between variations in body weight and increased morbidity and mortality but do not distinguish between voluntary and involuntary weight-loss events. The studies of psychologic hazards have been limited, and little convincing information is available. Without more compelling evidence of the risks of weight cycling, warnings overriding safe, effective weight-loss treatments for the obese are unwarranted. Appropriately designed studies are urgently needed to assess the long-term efficacy of procedures and treatments that promote weight-loss maintenance and to provide further analyses of the effects of weight cycling.