A case is presented with sudden onset of cachexia and anorexia with hypopituitarism, starting early and progressing gradually. After about 15 months the patient recovered; first he lost the anorexia, then the endocrine functions and growth became normal. Conflicting reports about hypopituitarism in anorexia nervosa and similar syndromes may be due to lack of longitudinal observations and the transient nature of the endocrine disorders.