For the public
You’re not the average. Your nutrition shouldn’t be either.
Personalized nutrition starts with you: your biology, your health history and the Tuesday you actually live. Then it keeps adjusting as you do.
Same food, different body
Good advice can still be the wrong advice for you.
Eat more fiber. Cut carbs. Go Mediterranean. None of that is bad advice, and some of it rests on decades of solid research. It was written for populations, though, and you are one person.
Cassidy Axelrod, a Certified Nutrition Specialist® on ANA’s team, saw this with a client who had followed every gut-health tip in her feed. Beans and lentils, extra vegetables, a prebiotic supplement each morning. The more fiber she added, the worse her bloating got. Her next step wasn’t more. It was less, while they worked out what was actually going on.
She isn’t unusual. When researchers fed 800 people identical meals and tracked their blood sugar, responses varied enormously from person to person, sometimes moving in opposite directions for the same food.2
Customized vs. personalized
More data isn’t the same as more personal.
Online quizzes, apps, an AI-built meal plan with exact macros and a grocery list. Each produces something fitted to your inputs, and sometimes that’s useful. But a plan can match your age, weight and goals perfectly and still miss your 12-hour shifts, your two kids, your 30-minute lunch break and the hypertension that runs in your family.
| Customized | Personalized |
|---|---|
| Starts with a form | Starts with a conversation |
| Uses whatever data you entered | Asks which information actually matters for you |
| Hands you a finished plan | Works through a process with you |
| Stays the same once it’s delivered | Changes when your symptoms, labs or life change |
| Asks, “Was this made for me?” | Asks, “Did understanding me change the recommendation?” |
Same data, different outcome. In a 2019 study, people received the same genetic test report. Some read it alone; others also had a practitioner help interpret it. The group with a practitioner made bigger changes to their diets.3 The difference came from what happened after the report arrived.
// The definition
We wrote the definition of personalized nutrition.
“Personalized nutrition is a field that leverages human individuality to drive nutrition strategies that prevent, manage, and treat disease and optimize health.”1
Lead author · Corinne Bush, MS, CNS · ANA CEO
Published in 2020 with nutrition scientists including Jeffrey Blumberg, Ahmed El-Sohemy and José Ordovás.
“Personalized” gets used for a lot of things in wellness. This is what we mean by it, and the paper names three parts that have to work together.
01 · Science & data
The science and data
Research on how your genes, metabolism, microbiome and lifestyle shape the way you respond to food. Lab work, genetic reports and wearable data all live here.
02 · Training
The training
Practitioners who know how to turn that information into decisions. A genetic report on its own is a document; someone has to read it in the context of your life.
03 · Guidance
The guidance
Care with you at the center. Your history, culture, preferences and goals count as evidence, right alongside the numbers.
What working with a practitioner looks like
Less like a meal plan. More like an investigation.
A diet starts with a framework and asks you to fit into it. Personalized care starts with you and works outward: who are you, what’s actually going on, and what makes sense given all of it?
“Tell me about your sleep.”
That was the first thing a CNS asked Sarah, who had come in ready to recite every diet she’d tried: four months of keto, a macro-counting app, a Mediterranean PDF from her last provider.
The conversation went to stress, to the afternoon crashes, to her medications. Then to ten years of gut trouble that earlier providers had answered with “add more fiber.” Her practitioner noticed the symptoms started around the same time as a new medication and flagged it for follow-up.
Sarah left without a laminated list. She had two things to track, one small change to try first, and the sense that someone had finally looked at her.
From our Substack · The difference between a diet and a protocol
The care cycle
Four steps, then around again.
04 Steps · repeating
01 · Assess
Assess
Symptoms, health and family history, labs, medications, sleep, stress, schedule, budget, culture and everything you’ve already tried. What you report counts as much as any test.
02 · Interpret
Interpret
Your practitioner reads it all together, looking at how your numbers and body systems relate to each other instead of only what got flagged.
03 · Intervene
Intervene
Changes to what, when and how you eat, plus movement, sleep, stress or targeted supplements. Usually one or two things first.
04 · Monitor & adjust
Monitor and adjust
You check back in and refine. A recommendation that needs changing hasn’t failed; it has told you both something new. Then the cycle starts again.
Who does this work
Practitioners trained for complexity, not checklists.
People come to personalized nutrition practitioners for digestive issues, blood sugar and heart health, hormone changes, inflammation, mood and memory, and for staying well longer.
What it takes to become a Certified Nutrition Specialist®
The CNS® is the advanced credential for personalized nutrition, accredited by the National Commission for Certifying Agencies (NCCA).
Education
Master’s or higher
A graduate degree in nutrition or a related field.
Experience
1,000 hours
Of supervised clinical practice.
Examination
Board exam
An advanced national certification exam.
Ongoing
Continuing education
Required to keep the credential active.
Many CNSs work alongside physicians, nurse practitioners, therapists and other clinicians, so your care stays connected.
ANA has also trained more than 22,000 healthcare practitioners in personalized nutrition. Your doctor, nurse practitioner or pharmacist may already bring this thinking into your care.
A quick gut check
Five questions to ask after your next appointment.
05 Questions
Q.01
Did they ask about your life before they talked about food?
Q.02
Did they read your labs as a whole, or only the flagged numbers?
Q.03
Did your history, medications and past attempts change the advice?
Q.04
Did you leave with a starting point instead of a total overhaul?
Q.05
Is there a plan to check back in and adjust?
“Was this made for me?” is the easy question. The better one: did understanding me change the recommendation?
Learn on your own
Start learning today.
Short, self-paced courses built by ANA’s nutrition science team for curious, non-clinical learners.
Getting Started with Personalized Nutrition
ANA’s 7 Essentials of good nutrition, how to spot nutrition red flags and where to find information you can trust.
Personalized Nutrition for GLP-1
What to eat and watch for while taking a GLP-1 medication, so the results you get are the ones you want.
Food, Mood, and the Mind
How your gut, your nutrients and your brain talk to each other, and what that conversation means for how you feel.
04Personalized Nutrition on Substack
Real stories and plain-language science from CNS practitioners and ANA’s team.
Common questions
Before you book.
Is personalized nutrition the same as a DNA test or a wearable?
No. Genetic tests, glucose monitors and sleep trackers can all be part of personalized care, and they can surface things you’d never notice otherwise. On their own, though, they’re data. Personalization happens when a trained practitioner interprets that data alongside your history and your life, then adjusts based on how you respond.
Do I need expensive lab tests to get started?
Not necessarily. Meaningful changes often start with a thorough conversation and standard assessments. Your practitioner may recommend further testing if it would change what they advise; more data is useful when it answers a real question.
How is a CNS different from a registered dietitian?
Both provide medical nutrition therapy and both play important roles in healthcare. They come from different training paths and paradigms; it’s not a ranking. CNS training centers on personalized nutrition, including functional and conventional lab interpretation and a systems-based view of the body. Many CNSs and dietitians work side by side.
Can I see a practitioner if there isn’t one near me?
Often, yes. Many practitioners in the ANA directory see clients virtually. Search the Practitioner Finder to see who’s available.
Find someone who asks about your sleep before your snacks.
The ANA is a 501(c)(3) nonprofit, founded in 1959. Course purchases and donations fund the education and advocacy that put nutrition at the center of healthcare.
References
- Bush CL, Blumberg JB, El-Sohemy A, Minich DM, Ordovás JM, Reed DG, Yunez Behm VA. Toward the definition of personalized nutrition: a proposal by the American Nutrition Association. J Am Coll Nutr. 2020;39(1):5-15. doi:10.1080/07315724.2019.1685332
- Zeevi D, Korem T, Zmora N, et al. Personalized nutrition by prediction of glycemic responses. Cell. 2015;163(5):1079-1094. doi:10.1016/j.cell.2015.11.001
- Araujo Almeida V, Littlejohn P, Cop I, Brown E, Afroze R, Davison KM. Comparison of nutrigenomics technology interface tools for consumers and health professionals: a sequential explanatory mixed methods investigation. J Med Internet Res. 2019;21(6):e12580. doi:10.2196/12580
- “Eight in ten midlife adults in the United States have one or more chronic conditions.” American Nutrition Association, Frontiers Policy Outlook.
