The Origins of the RD vs. RDN Confusion
For many years, the primary credential for a nationally certified food and nutrition expert was "RD," standing for Registered Dietitian. However, the Academy of Nutrition and Dietetics recognized a gap in public perception. While the public clearly understood the term "nutritionist," many were less familiar with the depth and breadth of a dietitian's training. To better communicate the professional's expertise, the optional "Registered Dietitian Nutritionist" (RDN) credential was introduced in 2013.
The rationale was straightforward: emphasize the nutrition and wellness aspects of a dietitian's training, especially compared to the unregulated title of "nutritionist." Anyone can call themselves a nutritionist, regardless of their education. The RD or RDN credential, on the other hand, is a legally protected title signifying a rigorous, standardized educational pathway and national certification.
The Path to Becoming an RD/RDN
The educational and professional requirements for becoming either an RD or an RDN are exactly the same. This process is highly regulated and includes several key steps:
- Master's Degree Requirement: As of January 1, 2024, candidates must complete a master's degree from a program accredited by the Accreditation Council for Education in Nutrition and Dietetics (ACEND).
- Supervised Practice: Candidates must complete a minimum of 1,200 hours of supervised practice in various settings, including healthcare facilities, community agencies, and food service organizations.
- National Exam: After completing their degree and supervised practice, candidates must pass a rigorous national registration examination administered by the Commission on Dietetic Registration (CDR).
- Continuing Education: To maintain their credentials, RDs/RDNs must complete 75 hours of continuing professional education every five years.
- State Licensure: Many states also require dietitians to hold a license, which is a separate but often related credential.
Where You See the Credentials in Practice
You will see nutrition experts using both designations, and it is entirely a personal choice or an institutional preference. Some practitioners prefer RDN because it is more explicit about their expertise in nutrition. Others, who were registered before 2013, might continue to use the traditional RD credential. The most important thing for the public to understand is that both titles denote the same high level of training and professionalism.
RD vs. RDN: A Side-by-Side Comparison
| Feature | Registered Dietitian (RD) | Registered Dietitian Nutritionist (RDN) |
|---|---|---|
| Meaning | Food and nutrition expert who has met standardized national criteria. | Food and nutrition expert who has met standardized national criteria. |
| Training Requirements | Same: Master's degree, 1,200+ hours supervised practice, national exam. | Same: Master's degree, 1,200+ hours supervised practice, national exam. |
| Scope of Practice | Same: Provide evidence-based nutrition counseling, medical nutrition therapy, food service management. | Same: Provide evidence-based nutrition counseling, medical nutrition therapy, food service management. |
| Credentialing Body | Commission on Dietetic Registration (CDR). | Commission on Dietetic Registration (CDR). |
| Introduction Date | Established decades ago. | Optional credential introduced in 2013. |
| Usage | Continues to be used by many dietitians. | Preferred by some dietitians to emphasize nutrition expertise. |
The All-Important Distinction from a "Nutritionist"
It's worth reiterating the key difference between an RD/RDN and someone who simply calls themselves a "nutritionist." In most areas, the title "nutritionist" is not regulated by law, meaning anyone can use it without any formal education, training, or certification. This stark contrast highlights why seeking out a professional with the RD or RDN credential is so important for those with specific health concerns or goals.
For example, while an unqualified nutritionist might offer general wellness advice, only an RD or RDN is legally able to provide Medical Nutrition Therapy (MNT). This critical service involves using nutrition to manage and treat diseases such as diabetes, kidney disease, or celiac disease. Furthermore, because of their rigorous training, RDs/RDNs are often integral parts of a larger healthcare team in hospital and clinical settings, working alongside physicians and other specialists. For this reason, always verify the credentials of any nutrition professional you consult.
Conclusion: RD or RDN—The Credentials That Matter
When it comes to answering the question, is it RD or RDN, the simplest answer is that there is no functional difference. Both credentials signify the same high level of education, supervised practice, and national certification through the Commission on Dietetic Registration. The addition of "Nutritionist" to the optional RDN credential was a strategic move to better communicate the profession's scope to the public. The vital distinction to remember is not between RD and RDN, but between these regulated titles and the unregulated term "nutritionist." To ensure you receive evidence-based and professionally accountable nutrition guidance, always look for the RD or RDN designation after a professional's name. They are the true experts in the field of food and nutrition science.
Additional Resources
- Commission on Dietetic Registration (CDR): The credentialing agency for the Academy of Nutrition and Dietetics. Explore their site for detailed information on credentialing and professional standards.
