Healthy body image is critical to adolescent development, and teens often diet and worry about their weight and appearance. However, for some youth these concerns become fixed and distorted, resulting in psychopathology. Eating disorders, particularly binge-eating disorder, anorexia nervosa, and bulimia nervosa, are serious, complex chronic disorders, which can be life-threatening. Differential diagnoses for eating disorders include: cardiac valvular disease, malabsorption syndromes; inflammatory bowel disease; chronic infections; thyroid disease; hypopituitarism, Addison disease; central nervous system lesions; cancer; and other psychiatric disorders including depression, obsessive-compulsive disorder, anxiety, and substance abuse. Eating disorders are difficult to treat, especially when presenting with comorbid diagnoses, and treatment depends on the severity of the illness. Primary health care providers play a critical role in assessment, monitoring of treatment progress, screening for and managing medical complications, and coordinating care with psychiatric and nutritional professionals.