What Exactly Is a Nutritionist?
A registered dietitian nutritionist could help you solve a mystery gut issue, boost your training, or develop a better relationship with food. Here's how to know what to look for.
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No one eats perfectly for their body all the time: a 2013 study of over 2,000 adults found that 74 percent of Americans regularly experience gastrointestinal distress. Whether you want to stop waking up ravenous at 2 A.M., find a sports drink that won’t give you acid reflux, or quit feeling bloated all the time, a better diet can make eating easier—and can help you train longer, harder, and faster.
But there’s a lot of nutrition advice out there, and plenty of it is bad. Earlier this year, researchers assessed dietary advice from a large sample of wellness influencers and found that only one in 12 recommendations was nutritionally sound. The quickest way to cut through the noise is to sit down with a certified expert. A good nutritionist can help you personalize your habits to your tastes, budget, and training plan and build a more functional relationship with food. So how do you find someone you can trust? And what can you do to get the most out of your appointment?
Look for the Letters
Anyone can call themselves a nutritionist in the United States—there’s no certification required to claim that title. Becoming a registered dietitian, on the other hand, requires a bachelors degree at an accredited university, a 1,200-hour internship, an exam, strict adherence to a code of ethics, and regular continuing education, explains Marisa Michael, an RD who specializes in sports nutrition.
Plenty of registered dietitians still use the term nutritionist, so keep an eye out for credentials. A licensed and registered dietitian will have RD, RDN, LD, LDN, or CDN after their name, depending on the state they live in. MS or MSc indicates a master’s degree in science, which isn’t a requirement for a dietitian but demonstrates a deeper research base. To find registered dietitians near you, visit www.eatright.org.
There are other certifications available in various states, all with significantly less focus on clinical practice and education. Holistic nutritionists do a six-month training, functional-nutrition practitioners do an 80-hour training, and intuitive health coaches do a 200-hour training. There are some well-educated experts who haven’t followed the typical registered-dietitian career pathway, which is why picking the right one can be tricky. Do your research and ask for recommendations, but if you’re new to it all, start with an RD.
Ask for an Athlete
If you’re training at a high volume, consulting with an RD who doesn’t have a sports background is sort of like getting a relaxing massage when you’d hoped for a deep-tissue one: maybe helpful, but not exactly what you were looking for. Someone who typically works with sedentary people may not understand the rigors of training for marathons or enduro races.
The acronym CSSD indicates that the person is a board-certified specialist in sports dietetics, which requires an additional 2,000 hours of sports-specific nutrition training. “For sports like ultra-endurance events or triathlon, it helps to have that personal experience to be able to relate to some of the nutritional challenges these athletes face,” says ultrarunning dietitian Kylee Van Horn of Fly Nutrition in Carbondale, Colorado.
Make a Plan and Take Notes
“When going to see a nutritionist, you should have a goal in mind, whether that’s gaining strength and lean mass, losing weight, or just eating more fruits and vegetables,” says Rebecca Guterman, senior dietitian at Mount Sinai’s Derald H. Ruttenberg Treatment Center in New York City. Once you’ve picked a nutritionist who seems aligned with the goals you have in mind, write a list of your questions and what you hope to achieve before you go.
You should also keep a food log for at least a few days ahead of your appointment. “It’s a better way for a dietitian to get a good view of what you’re eating on a daily basis, rather than you trying to remember it during your session,” says CrossFit coach and registered dietitian McKenzie Flinchum. Make sure you include hydration as well as general notes about digestive issues, stress, sleep quality, and energy levels. If you’re in heavy training (more than a few hours a week), log your workouts, too. If you’re really busy, snap pictures of everything you eat for a few days.
Watch for Red Flags
Plenty of RDs and nutritionists preach food doctrines that can be unhelpful at best and dangerous at worst. Here are a few warning signs to look out for at that first appointment.
“Does this person tell you you can never eat something, no matter what? That is unrealistic and not rooted in science,” says Guterman. “Be wary of those practicing in the extremes.” Caitlin Self, a Baltimore-based dietitian, encourages athletes to avoid any kind of restrictive eating, which can trigger a disordered relationship with food and lead to undernourishment. If you feel you’re being food shamed or leave feeling more disheartened than motivated, it’s time to look elsewhere.
The Pill Popper
“Be careful of anyone selling a product, especially a pill or supplement that you have to take in addition to following their plan,” adds Guterman. Recommending a specific brand of whey protein is fine, but suggesting you purchase their entire supplement or vitamin lineup indicates ulterior motives. For most people, the best way to get the nutrients they need is through a varied, whole-food-based diet.
The One Size Fits All
“A huge red flag to me is someone who preaches only one style of eating—like vegan or keto—without considering bio-individuality,” says Self. “We know there are genetic and environmental factors that affect which diet is best for each of us, it’s just a matter of being open-minded enough to uncover it.” The best nutritionist will be well versed in a wide array of diet patterns and can help you choose one suited to your tastes and needs.
A dietitian isn’t a psychologist. “Overstepping boundaries into mental health and therapy is a problem,” says Van Horn. A dietitian who thinks you need extra help should be recommending another expert, not taking matters into their own hands.
Change Takes Honesty and Time
A dietitian can’t help you as effectively if you leave out that second glass of wine or if you claim you want to gain muscle when you’re really hoping to lose weight. “I want people to show up ready to be completely honest and straightforward,” says Flinchum. “We’re not here to judge someone who eats dessert every day.”
A successful first visit should include talking through what your current diet looks like, discussing nutrition basics, and working together to set realistic goals, explains California-based registered dietitian Martha Lawder. You should walk away with answers to your specific questions and a rough action plan. But remember, this is only day one: nutritionists should not want or expect their clients to make immediate, sweeping changes. Expect to book a follow-up.
Tailored nutrition advice can be the final puzzle piece in your training, helping you meet your goals in sport and in life. But first you have to find the expert who is right for you.