Who Are the Experts in Nutrition Science?

When looking for credible nutrition information, one of the most important aspects to consider is the expertise of the individual providing the information.

What Does It Mean to Have Expertise in the Field of Nutrition?

Expertise in nutrition can be tricky to assess, because many people claim expertise yet lack formal training in the field. But formal training, obtained through advanced study at a college or university and assessed by meeting credentialing and/or degree requirements, is the best indicator of expertise in any field, because it shows an investment in gaining foundational knowledge from experienced educators and practitioners who specialize in the area. This level of expertise is very difficult to obtain without the rigor of a college or university training program. People may believe that they have gained expertise in nutrition through self-taught study, such as by reading books, studies, and articles; listening to podcasts; watching YouTube videos; and through observation of what foods make them feel good or ways of eating they enjoy. These sources of information can be valuable (though they can also sometimes contain misinformation), but it is difficult to truly develop self-taught expertise, because we are so easily led astray by our own biases and can be unaware of our blind spots about food and nutrition.


Several young adults are seated around a table together, laptops open. A woman with long dark hair stands at the front of the room, pointing at a white board filled with sticky notes.

Let’s consider for a moment why expertise is important. If you had an electrical problem in your home or a mechanical problem with your car, or if you had a broken bone or a heart attack, you probably wouldn’t seek services or treatment from a celebrity, a social media influencer, or a tech executive. Instead, you would look to someone with specific training in the issue facing you, such as an electrician or mechanic who had completed a vocational program and a supervised apprenticeship, or an orthopedist or cardiologist with years of specialized training in their fields. If you tore a ligament in your knee, you wouldn’t trust a cardiologist, much less a mechanic or a celebrity, to do orthopedic surgery on your joint. You also wouldn’t bring your car to a cardiologist to diagnose why the check engine light was on, or why it was making that funny noise. Nutrition is no different; if we’re looking for accurate information and advice, we should seek out experts with specific training and experience in the field.

This is not to dismiss other types of expertise that are related to food and nutrition. Traditional home cooks and formally-trained chefs have expertise in preparing tasty, comforting, or exciting food and in keeping food traditions alive. Farmers and home gardeners can share their knowledge about sustainable practices for producing food. Climate scientists can share how our food choices affect the health of the planet. And each of us has our own personal expertise in our own bodies, such as which foods seem to not agree with us, and which make us feel satisfied or energized or connected with our cultures. Knowledge about food can span many areas, but when it comes to information about how eating patterns affect our health, we want to look for someone with training and experience grounded in the science and practice of nutrition.

How to Spot an Expert

If you’re seeking a credible expert in nutrition, start by looking for professionals with the following degrees or backgrounds:

  • Registered dietitian nutritionist (RD or RDN)
  • Professional with advanced degree(s) (MS or PhD) in nutrition
  • Physician (MD) with appropriate education and expertise in nutrition

Registered dietitians or professionals with advanced degrees in the field of nutrition are the most credible sources for sound nutrition advice, because their training was most likely grounded in science-based nutrition information and practice. Physicians can also be good sources of nutrition information, depending on their education and background. But be mindful that medical schools generally offer minimal or no education and training in nutrition, so most physicians have limited knowledge in this field unless they have sought out specific nutrition training on their own.

Be skeptical of other official-sounding credentials, like “holistic nutrition practitioner,” or even just “nutritionist.” There are no national standards or regulations for what these titles mean. In many states, anyone can call themselves a “nutritionist,” and you could be taking advice from a well-qualified individual with a graduate degree in nutrition or someone who just took a single course or got a mail-order certificate. It’s worth taking a closer look at their training and credentials before assuming they have solid expertise in the field.

Keep in mind that every expert, regardless of their level of training and experience, is still human. No person can know everything or understand every perspective, and science is constantly evolving. Just as a single scientific study is never the last word on a scientific question, neither can a single expert have all of the answers. This is why good science reporters interview multiple experts and consider the scientific consensus (based on statements from professional organizations and publications like systematic reviews and meta-analyses) when they report on nutrition and health.

The video below delves further into how we can assess expertise in science and health, including some examples from the COVID-19 pandemic.

VIDEO: “Evaluate Expertise with Mike Caulfield” by CTRL-F, YouTube (May 22, 2020), 4:32.

Careers in Nutrition and Dietetics

There are several pathways to careers in nutrition and dietetics. Here’s a quick run-down:

  • Nutrition and Dietetics Technician, Registered (NDTR) – Earning this credential requires either a two-year associate’s degree plus supervised practice in community programs, healthcare or foodservice facilities, or a four-year bachelor’s degree from an accredited program. It also requires passing a national exam and completing continuing education to maintain registration. NDTRs often work under the supervision of an RD or RDN in healthcare, foodservice, community, and industry settings.1
  • Registered Dietitian Nutritionist (RD or RDN) – As of January 1, 2024, earning the RD or RDN credential will require a graduate degree (master’s or doctoral) in an approved program. The credential also requires completing a supervised internship program and passing a national exam, and continuing education is required to maintain registration.2 There are many career opportunities for people with the RD and RDN credential, including in clinical practice, such as providing medical nutrition therapy for specific medical diagnoses. RDs and RDNs are also able to bill insurance for their services.
  • Nutritionist – Unlike the RD/RDN and NDTR credential, there is no national standard for education and training for the title “nutritionist.” Some states require individuals to meet certain education and training requirements and be licensed to practice as a nutritionist, but others have no such requirements. Thus, employment opportunities vary by state but are generally more limited (and do not include clinical work in healthcare settings) for those practicing without the RD/RDN or NDTR credential.3Two women sit at a conference table. One woman is showing some printed materials to the other woman and they are talking together.

Dietitians and nutritionists plan food and nutrition programs, promote healthy eating habits, and recommend dietary modifications. Typically, to work in a clinical setting like a hospital or outpatient setting, the RD/RDN credential is required. For example, a dietitian might teach a patient with hypertension how to follow a lower-sodium diet or formulate special diets for patients being fed through a tube. But there are many types of jobs in nutrition, including in government agencies, companies, education, community, and non-profit organizations. No matter the setting or the clientele, working in the field of nutrition means helping people improve their dietary habits by translating nutritional science into food choices.

Here are some examples of career settings for dietitians and nutritionists:

  • Hospitals, clinics, long-term care, or other healthcare facilities, providing patient education and clinical care and tailoring foodservice and dietary recommendations to specific medical conditions and needs.
  • Day and residential facilities, such as day care centers and correctional facilities, planning meals and food purchasing.
  • Sports nutrition programs for teams, universities, or private clients, providing education and nutrition planning for athletes.
  • Food and nutrition-related companies and industries, such as grocery stores and food and supplement companies, working in communications, marketing, public relations, product development, research, or consulting.
  • Government agencies, administering federal food programs such as Women, Infants, and Children (WIC), Supplemental Nutrition Assistance Program (SNAP), or the National School Lunch Program (NSLP), coordinating communication campaigns, or creating or analyzing public policy.
  • Private practice, providing individual nutrition screenings for clients and guidance on food-related issues, such as planning enjoyable meals, chronic disease prevention, treatment of eating disorders, and weight reduction.
  • Community and public health settings, teaching and advising people about healthy eating habits.
  • Universities and medical centers, teaching students about nutrition or working as part of research teams to plan and carry out scientific studies.
  • Nonprofit organizations, such as anti-hunger organizations, food banks, public health organizations, and activist groups, providing nutrition-related expertise to help meet the organizations’ aims.

Whether you pursue nutrition as a career or simply work to improve your own dietary choices, what you are learning in this course is a step toward building your own expertise and being able to seek it out and recognize it in others.



  • University of Hawai‘i at Mānoa Food Science and Human Nutrition Program, “Careers in Nutrition,” CC BY-NC 4.0
  • Bureau of Labor Statistics, U.S. Department of Labor. (2019, September 4). Dietitians and Nutritionists. Occupational Outlook Handbook. https://www.bls.gov/ooh/healthcare/dietitians-and-nutritionists.htm


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Nutrition: Science and Everyday Application Copyright © 2020 by Alice Callahan, PhD; Heather Leonard, PhD, RDN; and Tamberly Powell, MS, RDN is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.

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