Principles of human nutrition

Foods need to provide all the building blocks for metabolism, tissue growth at reproduction, the energy required for all functions and activities, and some ‘essential’ compounds that cannot be synthesized. Nutritional science covers all the processes involved in achieving a healthy balance between requirements and the supply of nutrients, at the right time and in appropriate proportions, at cellular, organ, whole body and group/population levels. Nutritional status (what we eat, what we are, what we can do) should be assessed in all patients, by simple screening, with detailed evaluation when appropriate. Nutritional status is occasionally a sole cause or treatment of disease, but frequently an important contributor to disease aetiology and management, commonly affected by other treatments.