Toward the understanding of anorexia nervosa as a disease entity.

Five major areas in the study of anorexia nervosa have been defined: the descriptive area (1868-1914), the pituitary era (1914-1940), the era of rediscovery of the illness (1930-1961), the psychoanalytic era (1940-1967), and the modern era (1961- ). The illness as a biopsychosocial entity has been delineated. An integrated view of the disorder, recognizing multiple factor interaction in a vulnerable person, and an individualized approach to treatment, are proposed.