What Organization Certifies Nutritionists? Understanding Key Credentials

December 1, 2025 •

3 min read

According to the U.S. Bureau of Labor Statistics, employment for dietitians and nutritionists is projected to grow 7% from 2023 to 2033, faster than the average for all occupations. Understanding the varying credentials and which organization certifies nutritionists is crucial for anyone seeking to enter this growing field or find a qualified practitioner. While many different certifications exist, the most recognized are issued by specific, reputable credentialing bodies.

Quick Summary

Several organizations provide credentials for nutrition professionals, each with different educational and training requirements. Key certifications include the Registered Dietitian Nutritionist (RDN) and the Certified Nutrition Specialist (CNS), issued by the Commission on Dietetic Registration (CDR) and the Board for Certification of Nutrition Specialists (BCNS), respectively. The term 'nutritionist' is not always regulated, so understanding the certifying body helps evaluate a professional's qualifications.

Key Points

Commission on Dietetic Registration (CDR): The CDR is the organization that certifies Registered Dietitian Nutritionists (RDNs), the most widely recognized and regulated credential for nutrition professionals.
Board for Certification of Nutrition Specialists (BCNS): The BCNS is another reputable body that certifies nutrition professionals with advanced degrees, granting the Certified Nutrition Specialist (CNS) credential.
RDN vs. CNS: The RDN credential emphasizes a conventional medicine approach often used in clinical settings, while the CNS focuses on a personalized, functional medicine approach.
Unregulated Title: The term 'nutritionist' is not regulated in many areas, so verifying a professional's certification from a reputable organization is crucial.
Other Certifications: Other organizations like NASM and ACE offer certifications for specific niches such as sports performance or general wellness coaching, but these generally have a more limited scope of practice.
Continuing Education: Certifications from recognized bodies like the CDR and BCNS require ongoing continuing education to maintain credentials and ensure practitioners stay current with the latest scientific research.
Licensing Varies by State: State licensure requirements vary, so it is important to check with local health departments to understand the legal scope of practice for different certifications.

Certifying Bodies for Registered Dietitian Nutritionists (RDNs)

In the United States, the gold standard for nutrition professionals is the Registered Dietitian Nutritionist (RDN) credential, formerly known as Registered Dietitian (RD). The sole organization responsible for this certification is the Commission on Dietetic Registration (CDR). The CDR is the credentialing agency for the Academy of Nutrition and Dietetics and ensures that RDNs meet stringent educational and professional standards.

Pathway to Becoming an RDN

The process to become an RDN is structured and highly regulated, requiring several key steps to ensure a high level of competency and patient safety:

Education: Complete a bachelor's or master's degree from a program accredited by the Accreditation Council for Education in Nutrition and Dietetics (ACEND).
Supervised Practice: Complete a supervised practice program (internship) of 900-1200 hours, accredited by ACEND.
Examination: Pass the national RDN examination administered by the CDR.
Continuing Education: Maintain the credential through continuing professional education requirements.

Certifying Bodies for Certified Nutrition Specialists (CNSs)

Beyond the RDN, another highly respected credential is the Certified Nutrition Specialist (CNS). The Board for Certification of Nutrition Specialists (BCNS), an affiliate of the American Nutrition Association, certifies individuals as CNSs. This certification focuses on a functional medicine approach to nutrition, which emphasizes personalized, science-informed care.

Pathway to Becoming a CNS

The path to becoming a CNS involves different requirements compared to an RDN, focusing on advanced degrees and personalized nutrition:

Education: Hold a master's or doctoral degree in nutrition or a related field from an accredited institution.
Supervised Practice: Complete 1,000 hours of supervised nutrition practice experience.
Examination: Pass the comprehensive CNS examination.

Other Nutrition Certifications

It is important to recognize that the title "nutritionist" is not legally protected in many places, meaning a person can call themselves a nutritionist without specific qualifications. This has led to a proliferation of different certifications with varying levels of rigor. Some notable organizations offering certifications include:

Clinical Nutrition Certification Board (CNCB): Offers the Certified Clinical Nutritionist (CCN) credential, which focuses on advanced clinical nutrition.
National Academy of Sports Medicine (NASM): Provides a Certified Nutrition Coach (CNC) certification, which focuses on sports performance and coaching.
Precision Nutrition (PN): A large education company that offers coaching certifications focused on evidence-based nutrition science.
American Council on Exercise (ACE): Provides a Fitness Nutrition Specialist Certification.

RDN vs. CNS: A Comparison of Credentials

Selecting the right type of nutrition professional depends heavily on an individual's needs. The choice often comes down to the fundamental differences in training and philosophy between the RDN and CNS credentials.


Feature	Registered Dietitian Nutritionist (RDN)	Certified Nutrition Specialist (CNS)
Certifying Body	Commission on Dietetic Registration (CDR)	Board for Certification of Nutrition Specialists (BCNS)
Educational Path	Minimum of a master's degree from ACEND-accredited program.	Master's or doctoral degree in nutrition or related field.
Internship Hours	900-1,200 hours in highly structured, competitive programs.	1,000 hours of supervised practice, more customizable.
Primary Focus	Conventional medicine and general population guidelines, often in acute care settings like hospitals.	Functional and personalized medicine, often in private practice or wellness centers.
Medical Nutrition Therapy	Can legally provide Medical Nutrition Therapy (MNT) in most states.	Cannot provide MNT in most states unless also licensed as a dietitian.
Licensure	State licensure is often required and recognizes the RDN credential.	State licensure may vary and might require additional steps depending on the state.

Conclusion: Choosing the Right Practitioner

When seeking nutrition advice, the certifying organization and the specific credential held by a practitioner are key indicators of their training and scope of practice. For medical nutrition therapy and acute care, an RDN certified by the Commission on Dietetic Registration is the most qualified professional. For a personalized, functional medicine approach, a CNS certified by the Board for Certification of Nutrition Specialists may be a better fit, provided they meet state licensure requirements. For general wellness and sports performance, credentials from organizations like NASM or ACE can also be valuable. Always verify a professional's credentials through the respective certifying body to ensure they are properly qualified for your specific needs. This diligence protects consumers from unqualified individuals and ensures they receive the highest standard of evidence-based care.

Frequently Asked Questions

An RDN, or Registered Dietitian Nutritionist, is a legally protected title for a credentialed professional who has completed specific, rigorous educational and training requirements set by the Commission on Dietetic Registration (CDR). The term "nutritionist" is not protected in many places, meaning anyone can call themselves one without formal training. All RDNs are nutritionists, but not all nutritionists are RDNs.

To ensure a nutritionist is qualified, look for credentials from reputable organizations, such as an RDN from the Commission on Dietetic Registration (CDR) or a CNS from the Board for Certification of Nutrition Specialists (BCNS). You can verify credentials through the certifying body's website or check your state's licensing board.

A Certified Nutrition Specialist (CNS) is trained in advanced personalized nutrition, but their ability to provide medical nutrition therapy depends on state-specific licensure laws. In most states, only an RDN is legally authorized to provide medical nutrition therapy. You should check your state's regulations to confirm a CNS's scope of practice.

The Academy of Nutrition and Dietetics is the professional organization for RDNs. Its credentialing arm, the Commission on Dietetic Registration (CDR), oversees the RDN certification process, setting the standards for education, practice, and the national exam.

Certifications from fitness organizations like NASM or ACE are valuable for fitness professionals who want to incorporate general nutrition coaching into their practice. However, these certifications typically do not grant the same scope of practice as an RDN or CNS and are focused more on general wellness than clinical or medical nutrition therapy.

Maintaining a reputable nutritionist certification, such as the RDN or CNS, requires ongoing continuing professional education (CPE). The CDR requires RDNs to complete 75 CPE units every five years, while the BCNS has its own recertification standards for CNSs.

You can verify an RDN's credentials through the Commission on Dietetic Registration website, and a CNS's credentials through the Board for Certification of Nutrition Specialists website. Additionally, many state health departments or licensing boards offer online portals to check if a professional is licensed in your area.