"If I gain any weight, I'll lose all control." These words, spoken by a 14-year-old anorexia nervosa patient, show just how serious eating disorders can be for teenagers, disturbing numbers of whom are dissatisfied with their bodies. For some, mostly girls, thoughts about food and their bodies consume their lives and lead to such life-threatening eating disorders as anorexia nervosa or bulimia nervosa. This guide to eating disorders for...