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What is a Registered Dietitian Nutritionist?

Many people mistakenly use the terms “dietitian” and “nutritionist” interchangeably. Although these two professions are related, they do have distinctive categories. The biggest difference between dietitians and nutritionists lies in the legal restrictions that each title carries. Anyone can call themselves a nutritionist, but only a registered dietitian (RD) or registered dietitian nutritionist (RDN) has completed multiple layers of education and training established by the Accreditation Council for Education in Nutrition and Dietetics (ACEND). In addition to holding a bachelor’s degree, an RD or RDN must fulfill a specially designed, accredited nutrition curriculum, complete an extensive supervised program of practice and pass a rigorous registration exam. What’s more, roughly half of all RDs and RDNs hold graduate degrees and many have certifications in specialized fields, such as sports, pediatric, renal, oncology or gerontological nutrition. The best way to remember it is, every dietitian is a nutritionist, but not all nutritionists are dietitians.

What is required to be a Dietitian?

According to the Academy of Nutrition and Dietetics, registered dietitians are required to complete a formal education program that results in at least a baccalaureate degree. Many dietitians will also hold advanced degrees, such as Master’s Degrees in related fields completed during or after their internship. In addition, the program must provide coursework that covers subjects in: food and nutrition sciences, computer science, chemistry, business, food service systems management, microbiology, sociology, biochemistry, physiology, anatomy, and economics.


Under the Academy of Nutrition and Dietetics (AND) rules, all Dietetic Internships must be at least 1200 hours in length. Each internship lasts from eight to 24 months and they must be an ACEND accredited program. After completion degree in a nutrition related field with required coursework and 1200 hours of qualified internship time, an individual must successfully pass the CDR registration examination to obtain their registered dietitian (RD) or registered dietitian nutritionist (RDN) credential. After filing for, and obtaining, state licensure, a RDN must complete continuing professional education credits each year needed to maintain registration.

What does a Registered Dietitian Nutritionist do?

Dietitians are highly qualified professionals educated in science, management, human development, and health of populations. As trusted professionals, dietitians fill many roles, depending on where they work. Some examples from the Academy of Nutrition and Dietetics include:
● Nutrition specialists who counsel and support clients to make changes in their eating habits to promote health and prevent chronic illness such as high blood pressure, diabetes, heart disease, cancer, kidney disease and other nutritional deficiencies
● Policy makers who advise government at all levels on population­ wide strategies to improve the health of Americans such as school nutrition guidelines, sodium reduction in processed foods, advertising to children
● Leaders in all aspects of food systems, including the safety and availability of our food, food service management, and food production and marketing
● Researchers who discover new and better ways to enhance patient care, promote health and prevent nutrition­ related illnesses
● Educators who prepare future dietitians and other healthcare professionals for practice