You Asked: What Is the Difference Between a Nutritionist and a Dietitian?

A lot actually.


nutritionist dietitian

Photo via Getty Images/Milkos

If you’ve ever considered working with a professional to fine-tune your nutrition you may have been stuck between a rock and a hard place. What I mean is everyone seems to claim that they are an expert when it comes to telling you what to eat, when to eat, and how much to eat, but how do you know who to trust? And more importantly, how do you know who is worth your time and money? There are endless titles and credentials out there and it’s important to know the difference, especially if you’re dealing with any type of medical condition. We chatted with Deanna Belleny, a registered dietitian and program manager at Harvard Medical School who co-founded the non-profit Diversify Dietetics, to walk us through the most common titles you’ll see in the space: nutritionist and dietitian. Because yes, there is a difference.

You Asked: What is the difference between a nutritionist and a dietitian?

The answer: All registered dietitians are nutritionists but not all nutritionists are registered dietitians.

The details: 

The answer to this common question can be convoluted and confusing. How can a registered dietitian be a nutritionist but a nutritionist not be a registered dietitian? To break it down, let’s start with what it takes to obtain the title of registered dietitian.

According to the Academy of Nutrition and Dietetics these are the requirements:

  • Earned a bachelor’s degree with course work approved by the Academy of Nutrition and Dietetics’ Accreditation Council for Education in Nutrition and Dietetics (ACEND). Coursework typically includes food and nutrition sciences, foodservice systems management, business, economics, computer science, sociology, biochemistry, physiology, microbiology and chemistry.
  • Completed an accredited, supervised practice program at a health care facility, community agency or foodservice corporation.
  • Passed a national examination administered by the Commission on Dietetic Registration.
  • Completes continuing professional educational requirements to maintain registration on an ongoing basis.

Belleny adds that starting in 2024 entry level registered dietitians will be required to have a masters degree and that the supervised practice, which totals more than 1,200 hours of unpaid work, is often the hardest part. “It’s very competitive and requires you to go through a matching process,” she explains. “During the process you rank the programs you are interested in applying to and then are matched based on how high you rank. So there is some strategy involved.” And on top of that, you must be in a financial situation that allows you to work for a year without getting paid—which is another topic all together.

When it comes to nutritionists ( i.e. holistic nutritionist, functional nutritionist, sports nutritionist, etc.) anyone can call themselves that, Belleny says. Albeit some type of exam or schooling might be involved but it will not be as intensive as what a registered dietitian goes through. Because the term “nutritionist” is more widely known, and in an effort to help people become more familiar with the work that dietitians do, the Academy added a new credential, Registered Dietitian Nutritionist (RDN), that registered dietitians can choose to use if they so wish. Hence: All registered dietitians are nutritionists but not all nutritionists are registered dietitians.  

“Registered dietitians get taught from day one the importance of looking into the literature and reading through evidence-based research for what the science says about nutrition claims,” Belleny tells me. So, if you’re debating keto or intermittent fasting there’s a good chance a registered dietitian has no stake in the game and they are able to “think critically about the evidence that is out there and integrate it with the needs and experiences of their clients,” Belleny adds.

Dietitians look at your nutrition as a piece to a whole and keep in mind not only the socioeconomic and cultural barriers some people face when it comes to healthy options, but also the way in which your food choices and behavior around eating affects other aspects of your life. And there are many specialities a dietitian can focus on to give you the care you need. As a Health at Every Size dietitian Belleny supports people of all sizes in finding compassionate ways to take care of themselves. “All bodies are different and they are meant to be different” she says. “As clinicians we should focus on ways to help our clients without bringing in biases, discrimination, or assumptions we have based on their size, color, age, race, gender, abilities, or orientation. And if we can constantly look through this lens it can challenge us to provide better care.”   

This is also a friendly reminder that it is outside a personal trainer’s scope of practice to give nutrition advice more detailed (i.e. nutrition plans, specific calorie breakdowns, etc.) than basic guidelines and recommendations. If you are interested in working with a dietitian visit: eatright.org to find a dietitian near you.