Repeated weight cycling in obese mice causes increased appetite and glucose intolerance.

Obesity is an ongoing global public health problem. For many people dieting is the preferred method of combating elevated body fat. Weight lost during caloric restriction is often soon regained and so a pattern of recurrent dieting develops. Here an individual's food intake fluctuates up and down with intermittent periods of normal eating and restrained eating. The metabolic consequences of 'yoyo dieting' or 'weight cycling' are not well understood. Here we monitor the effects of multiple, repeated dieting periods on body composition and metabolic health in overweight mice. Compared to mice that were continuously fed a high fat diet, the energy expenditure of diet-cycled mice was reduced. This resulted in mice rapidly regaining body weight upon the reintroduction of high fat chow diet subsequent to periods of caloric restriction. Diet cycling also increased the appetite for high fat chow and diminished glucose tolerance. These data demonstrate the detrimental effects of diet cycling upon metabolic health.