See what went well, what didn’t and when you’re better off sticking with a professional.
Reviewed by Dietitian Jessica Ball, M.S., RD
Key Points
- ChatGPT is helpful for basic nutrition tips but lacks nuance for personalized health advice.
- AI can brainstorm meal ideas but should not replace guidance from a registered dietitian.
- For medical conditions or complex goals, consult a healthcare professional, not ChatGPT.
When you’re looking online for nutrition advice, the sheer number of articles, studies and social media videos online can feel overwhelming. That can make it tempting to rely on artificial intelligence (AI) platforms like ChatGPT as a one-stop-shop for nutrition information. But can ChatGPT provide reliable answers? And when is it best to use it—and when should you turn to a health care professional instead?
As a registered dietitian with more than 20 years of experience, I put ChatGPT to the test to find out. I also consulted nutrition and technology experts who work with AI to learn their best practices for using these platforms for nutrition advice. “The built-in knowledge of AI models is pulled from a wide range of sources, which are both trustworthy and untrustworthy,” says Jonathan Razzaan expert in computer science and technology.
Here’s what went well, what didn’t and when to seek professional guidance where ChatGPT’s responses fall short.
How I Tested ChatGPT
I created a series of prompts and evaluated each response using my expertise as a registered dietitian. I started with common, general nutrition questions, then moved to increasingly personalized requests.
Some general questions I asked included:
- What are the healthiest foods to eat?
- How much protein should I eat in a day?
- What are three balanced meals I can make with these ingredients?
- Is this news story accurate, and what does it mean?
- Can you create a 1-week 1,500-calorie meal plan?
Overall, ChatGPT provided some helpful, specific tips for these more basic questions, and always included the caveat that personalized needs vary. It also recommended speaking to a registered dietitian or other qualified healthcare professional for individual guidance.
Some useful capabilities were its ability to suggest meal and recipe ideas using certain pantry items, create a fairly accurate meal plan and break down a media headline that shared a common misconception—that carbs inherently lead to weight gain.
Chrissy Carroll, M.P.H., RD, says if you’re trying to make sense of a media headline, there are ways to prompt ChatGPT more effectively. “For example, if the story is referencing a new nutrition study and you want to better understand it, you could give ChatGPT the study link and ask it to explain it at a 5th-grade level. It might sound silly, but it can be incredibly helpful!” she shares.
Then, I moved on to more personalized questions, such as:
- Can you create a low-carbohydrate meal plan that has at most 100 grams of carbs each day?
- I have high cholesterol and high blood sugar. How should I eat to manage this?
- I have a newly diagnosed gluten allergy. Can you create a list of what I can and can’t eat?
- What foods should I avoid if I take certain medications?
- How can I lose 10 pounds in 2 weeks?
While ChatGPT generated an answer for each question, the more personalized prompts required additional context and a longer back-and-forth. In some cases, ChatGPT asked for more information—such as my food preferences, whether I had celiac disease or just a gluten sensitivity and which specific medication I was asking about. It also recommended consulting a pharmacist about medication-related questions and cautioned against rapid weight loss.
What ChatGPT Did Well
It answered basic nutrition questions
ChatGPT did a pretty good job answering basic nutrition questions related to specific foods and recommendations for the general public. I found that the foods it recommended for overall health were appropriate, and it provided a well-rounded recommendation without bias toward a certain way of eating.
After refining some prompts, it provided a usable grocery list aligned with a general healthy diet. When I first asked, the responses were fairly general, such as “nuts and seeds.” But after I asked clarifying questions like “which nuts are best for weight loss?”, it offered more specifics and mentioned how pistachios in the shell are a particularly good choice as they can naturally slow down eating.
It offered practical meal and recipe ideas
“ChatGPT can be useful for brainstorming ways to add more vegetables to meals, coming up with meal or snack ideas based on ingredients someone already has,” says Drew Hemler, M.Sc., RD, CDN, FAND. I put this to the test and found it generated practical meal and snack ideas, as well as simple recipes when given straightforward tasks, such as making chicken noodle soup.
Carroll adds you can also ask ChatGPT for specific meal ideas based on your registered dietitian’s recommendations. “You could share a list of what’s in your fridge, freezer and pantry, and ask it to provide recipe links that use the ingredients you have on hand,” she says.
It gave me a guide starting point
ChatGPT provides answers in seconds, which can be helpful if you’re pressed for time. Hemler reiterates that one of its biggest appeals is its accessibility and ability to generate nutrition information right away. That said, it repeatedly advised speaking to a registered dietitian, doctor or other healthcare professional for personalized guidance before making changes, which I appreciated. This was especially prominent when I asked more individualized questions.
Where ChatGPT Fell Short
It tended to agree with my assumptions
ChatGPT showed a strong tendency to agree with how I framed a question in order to increase satisfaction. While it can feel nice to have your nutrition concerns validated, it can result in one-sided or biased information.
For example, I asked ChatGPT about certain nutrition practices I know are not backed by science, such as completely avoiding carbs. When I framed my prompt in a way that suggested I supported cutting out carbs, ChatGPT was more likely to agree with that perspective, responding with statements such as “since cutting carbs works for you, doing this is a good strategy.” But when I framed the same topic more negatively, it was more likely to agree that avoiding carbs wasn’t a good idea.
“The level of sycophancy, or agreement, can vary based on the AI tool and model,” says Carroll.
It sometimes overstated research
“My biggest concern isn’t that ChatGPT can be wrong, but more so that AI can give information that is incomplete, outdated or overly generalized,” says Hemler, noting it can present that information in a way that sounds remarkably confident and convincing. This is particularly concerning when it comes to interpreting nutrition research studies.
I saw this most often in the language ChatGPT used to interpret research. At times, it made definitive statements like “this nutrient prevents this disease,” when the results were not strong enough to support causation. If I were breaking down the same research, I would use more conservative language, such as “this nutrient is associated with lower disease risk.” This makes it clear that the study doesn’t prove cause and effect, and that other factors like overall eating patterns and physical activity may have influenced the results.
It missed important context
While ChatGPT can attempt to personalize nutrition advice based on the information you give it, I found it missed the mark in terms of context and nuance. This includes factors it may not know, such as what has worked for you in the past, your home and work environment and your access to food and health care. These factors are important to consider to provide more complete guidance.
Hemler emphasizes that while ChatGPT can produce an answer that feels very individualized, it doesn’t incorporate clinical reasoning or comprehensive assessment a registered dietitian would provide.
“Because of this, I think AI-generated nutrition guidance should be viewed as information to evaluate, rather than something that should automatically be treated as authoritative advice,” Hemler adds. When it comes down to it, the information ChatGPT provides cannot—and should not—replace personalized advice from a qualified professional who has experience working directly with people.
Professional Guidance Is Important
Hemler suggests thinking of ChatGPT as a starting point, not as the final authority for your nutrition plan. Here are a few key scenarios where it’s especially important to seek professional guidance from a registered dietitian.
When You Have Individual Nutrition Needs or Goals
Consider professional guidance when you’re navigating individual goals such as weight loss or GLP-1 nutrition, pregnancy, sports performance or other situations where your nutritional needs may differ significantly from general recommendations. A registered dietitian can assess your intake, lifestyle, preferences and goals, and adjust the plan as your needs change.
When You’re Managing a Medical Condition
If you have a chronic condition such as diabetes, heart disease, kidney disease, food allergies, digestive conditions or another health concern, nutrition recommendations need to be tailored to your diagnosis, lab results, medications and treatment plan. A credentialed nutrition expert can see the bigger clinical picture in a way that AI cannot.
When Your Relationship with Food Is Causing Distress
If you’re severely restricting food, binge eating, feeling anxious or guilty about eating or becoming preoccupied with your weight, ChatGPT shouldn’t be your primary source of guidance. A healthcare professional like a registered dietitian can provide appropriate support and recognize when additional care may be needed.
The Bottom Line
ChatGPT can be a helpful starting point for answering basic nutrition questions, brainstorming meals and recipes or making complicated research easier to understand. But its answers aren’t always accurate, unbiased or nuanced enough to guide individualized nutrition decisions. Experts recommend treating ChatGPT or any AI program as a tool—not the final authority—for nutrition and health information. Always turn to a registered dietitian or other qualified healthcare professional when your needs involve medical conditions, medications, complex health goals or a more personalized approach.