Dietetics is defined as 'the application of the science of nutrition to the human being in health and disease.' However, the term 'dietitian,' used to describe a practitioner of dietetics, was in use long before the science of nutrition had become an accepted discipline.
Nutrition is the supply of materials that organisms and cells require to live. Humans need seven major types of nutrients to function. A nutritionist studies nutrients, how the body uses them, and the relationship between a person's diet and their health. Here, learn more about nutrients and what a nutritionist does.