Anorexia nervosa commonly occurs during adolescence, a critical period for the acquisition of peak bone mass. Osteopenia is an early and serious complication associated with anorexia nervosa. Whether the osteopenia observed in adolescents with anorexia nervosa is reversible is unknown. The possible mechanisms for the osteopenia observed in adolescents with anorexia nervosa are complex and poorly understood. The purpose of this paper is to review a number of the identified factors that influence the attainment of peak bone mass in anorexia nervosa and to examine the best treatment options for optimizing skeletal mineralization in adolescents with anorexia nervosa.