Despite the relevance of eating disorders in the past years, the pure core of these mental disorders remains unknown. In this regard, it is not a surprise that the biopsychosocial model is the best way to go forward in order to understand and to improve the different approaches, biological (mainly neurobiological), psychological, and social, in managing these disorders. Eating disorders are frequent pathologies, many times severe and often devastating for patients and their families. Biological, psychological, and social factors are always involved in these disorders, and knowledge about the influence of these factors helps us to better understand eating disorders. This book includes different studies about main topics of eating disorders and is useful for psychologists, doctors and others interested in this disorder.