Dietetics comes from the Greek word "diaita", which means lifestyle. The role of proper nutrition in the prevention of disease was already articulated by Hippocrates. Since then, the perception of dietetics has changed over the centuries, depending on the scientific and ideological views of the time. Prior to the 19th century, dietetics sought to regulate not only nutrition but also exercise, bowel movements, rest and sex life.
Today, dietetics has developed into a science in its own right, based on nutritional science, investigating the metabolic processes that are shaped by disease, and exploring the principles and main interrelationships of dietetics. It deals with the importance and role of nutrients, metabolic processes and nutrient requirements at different ages and in different states. It also examines food ingredients, the effects of food on health, how they are used and their role in health promotion.