In this thematic unit, we will analyze the concept of nutritional value of foods as well as the properties and needs of different nutrients. In addition, we will discuss the concept of energy balance, its components and its regulation as well as body composition and the assessment of the nutritional status. Also, we will analyze the physiological and metabolic processes associated with nutrition. Finally, the role of food additives and their relationship with health will be evaluated. We will consider the different nutritional properties from the perspective of biotechnology, the generation of new foods and their role in health from a preventive and therapeutic point of view.