Prospective relation of dieting behaviors to weight change in a community sample of adolescents

Although treatment studies suggest that weight loss programs do not have lasting effects, little research has examined the relation of dieting to weight change in prospective community studies, and none have done so with adolescents. This study examined the effects of dieting on body mass over a 9-month period within a community sample of adolescents (N = 396). Continuous measures of dieting behaviors predicted a relative increase in body mass (for males and females), whereas self-labeled dieting predicted decreased body mass (for females). Divergent findings resulted because self-labeled dieting reflected more extreme dietary efforts. Analyses also suggested that dieting was quadratically related to body mass, wherein low to moderate dieting predicted weight gain and extreme dieting predicted weight loss. Results highlight the importance of measurement issues and suggest that dieting only leads to weight loss for those adolescents employing extreme dietary behaviors.