Registered Dietitian, Nutritionist, Health Coach—What’s The Difference?

Get legit advice from a legit nutrition pro.

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When it comes to training, you consult with a coach. For medical issues, you turn to your doctor. It would make sense, then, to seek out a professional when you’re ready to get serious about fueling for your sport. But who? When it comes to nutrition, experts are easy to find—nutritionists, registered dietitians, and nutrition coaches are in abundance in the triathlon community. But though many use these professional titles interchangeably, they’re not all created equal.

“The term nutritionist isn’t regulated, so technically, anyone can call himself or herself a nutritionist, even with no formal training or with a two or three week online course in nutrition,” explains Kim Schwabenbauer, a former pro triathlete and current Registered Dietitian. Same for the title of “nutrition coach”—it’s a term that anyone can use, be it someone with a doctorate in nutrition or a vegan/paleo/keto enthusiast with no formal training.

At best, utilizing the wrong professional can lead to wasted money. At worst, it can cause serious health problems. That’s why it’s important to seek out someone whose advice is backed up by the right kind of credentials.

Registered Dietitian

Registered Dietitians, or RDs, are the only professionals with the education and credentials to provide medical nutrition therapy. To earn this title, a person must have at least a bachelor’s degree (in 2024, this will be raised to require a Master’s degree) with a focus in dietetics, complete a minimum of 1,200 hours of supervised practice hours, and pass a national examination administered by their national licensing body. Additionally, they are required to re-certify every five years by completing a minimum of 75 hours of ongoing coursework to ensure they are up-to-date on the ever-growing body of nutritional research. 

For athletes with medical conditions, such as diabetes, Crohn’s, anemia, or thyroid disorders, an RD is a critical part of the medical team, as they are the only nutrition professionals who are able to prescribe diets to patients like a doctor prescribes medication.

Some RDs go one step further, adding CSSD to their RD titles. This means they are board-certified specialists in sports dietetics. This requires 1,500 additional hours of specialty practice working with athletes on top of their original RD requirements. This qualifies CSSDs to assess and monitor body weight and composition, analyze supplements for safety and efficacy, and provide sport-specific counseling around fueling, hydration, and injury/recovery nutrition protocols.


In contrast, nutritionists can vary widely in the training required for the titles they claim. In some states, one can become a “certified nutritionist” or “licensed nutritionist” by meeting requirements set by the particular state—New York state, for example, certifies those with a bachelor’s or associate’s degree and anywhere from six months to 10 years of supervised experience. But most states have no requirements at all for using such titles. 

Nutritionists can be used in an educational context—say, helping clients make better food choices—but cannot make specific dietary prescriptions in the same way an RD can. That’s because a lack of clear credentialing renders most non-RDs ineligible to be covered by insurance. “If they don’t have professional liability insurance, and you get into a bad spot with advice they have provided, they may be liable, but you have to sue the individual for damages,” says Schwabenbauer. 

Nutrition Coach, Consultant, or Guide

There are many other titles doled out by for-profit training programs for health coaches or wellness consultants, each with varying degrees of educational requirements, so it’s not always clear what “certified” means. These titles can also be utilized by someone who is self-taught, so it’s not always clear what, if any, training such professionals have. 

Social media has facilitated an increase in the visibility of this subset of nutritional professionals. There are many who style themselves as “experts,” and some include multiple letters after their names, but deeper investigation reveals that though their follower count may be huge, their academic training is nonexistent. This can be particularly true for people who advocate for and sell products related to extreme, unproven diets—their methods may be intriguing and their results visually appealing on social media, but such approaches can also be ill-advised (or even dangerous).

How Do I Find the Right One for Me?

It’s best to take your nutrition advice from someone with some letters after their name—specifically, RD. These are the experts who meet the most rigorous requirements for advising people on diet and nutrition. CSSD is also a good set of letters, if you’re looking for advice specific to athletes. As for the rest, because they’re not being regulated by a board and therefore aren’t held to the established standards, athletes should be careful to receive services from uncertified individuals.

To find the best expert for you, Schwabenbauer suggests the following:

  • Ask your fellow athletes who they’ve worked with previously. “Look for someone with a positive reputation in the community. They will have good reviews from previous clients and athletes, both in quality and care of service.”
  • Find someone with specific knowledge to the demands of your sport—a short-course athlete who does gravel riding in the offseason will have different needs from someone training for three Ironmans in one year.
  • “It’s also good to look for someone who has a coaching style you like,” explains Schwabenbauer. “How often will you talk to them? When? In person, on the phone, or via e-mail? What resources do they have available? Will they require bloodwork as part of their analysis? These are all important questions to ask!”
  • If you follow a special diet, such as vegan or gluten-free, ask if they have knowledge and experience with that specific lifestyle.
  • Ask about their nutrition philosophy: “These are very different between professionals. You want to have someone you can talk to and trust.” 

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