[To start eating again could be dangerous].

A 36-year-old woman with anorexia nervosa and resulting malnutrition decided to change her life and eat properly. One day after the refeeding start, instead of feeling better she felt much worse: fatigue, nausea and leg swelling occurred. She consulted our emergency department. A «refeeding syndrome» has been diagnosed. In this case report we discuss causes, clinical presentation and treatment of this illness. The aim is to make practitians aware about the existing of this disease even with oral refeeding. Warning signs have to be interpreted correctly in order to avoid dramatic consequences.