Access to adequate food is a fundamental human right. There is no doubt that nutrition is essential in maintaining health and preventing or treating disease. Particularly when patients are affected by disease-related malnutrition, their risk of adverse clinical outcomes increases significantly and optimizing nutritional support becomes mandatory. There is ongoing debate about what constitutes an optimal nutritional care process in terms of screening, assessment, and use of nutritional support in different patient populations. Issues include dose and quality of proteins and total energy, route of delivery, and whether or how nutritional support needs to be adjusted for specific medical and metabolic conditions. As we move toward personalized medicine, which is based on patients’ individual needs, an understanding of these different factors is important. Well-planned clinical studies of high methodological quality are needed to develop the best approach to providing individualized nutritional support.