Critically ill children are usually fed artificially, enterally by stomach or small intestine tube or parenterally directly into the blood. They often suffer from over- or malnutrition, digestive system disorders, muscle loss and failure to thrive. Studies show that nutritional counselling specialized in intensive care medicine in an interdisciplinary setting can improve the nutritional situation of these children. Optimal nutrition should prevent nutritional deficits, promote the healing process and, at best, shorten the length of stay in the intensive care unit.