Hospital malnutrition is an insidious problem which is responsible for many complications. Critically ill patients are frequently hypermetabolic with increased nutritional requirements, and are exposed to the risk of underfeeding. The case report presents the case of a patient which stayed 22 days in the intensive care unit (ICU), and whose nutritional support failed: he ultimately died of surgical and infectious complications. An optimal support includes a early metabolic support provided as glucose-insulin-potassium infusion and antioxidant micronutrients, with an enteral nutrition initiated on days 3 or 4. It is frequently difficult to reach energy targets with exclusive enteral nutrition: if the latter is not reached after 5-6 days of enteral feeding, combination with parenteral nutrition enables worsening of the energy deficit. Transition to oral feeding is another critical event which may expose the patient to underfeeding: prescription of oral supplements and/or maintenance of overnight enteral feeding providing 50-75% of energy requirements helps overcome this period. The case illustrates the importance of monitoring daily and cumulated energy balance.