Illustration: Olivier Heiligers
Almost every day, at least one patient asks nurse practitioner Nicole Newman about Red Dye No. 3. If not that, it’s microgreens powder, adaptogens, lion’s-mane supplements, or some other esoteric ingredient or nutrient. “Patients will come at me with these highly specific things,” said Newman, who practices family medicine in rural western Michigan. “Tell me what you know about this,” they demand. “And usually, the answer is ‘nothing,’” she told me.
She can offer generalities: eat leafy greens, drink water, that sort of thing. “But people don’t want that,” Newman said. When it comes to nutrition, “they want, ‘Well, what really am I supposed to be doing?’” They want specifics. She empathizes with her patients. Most seem to be earnestly seeking out ways to improve their health through diet — and they’re doing so by asking an actual health-care provider for advice instead of relying on podcasts or TikTok. “It should be a reasonable ask from my patients, that if they want help with their nutrition, I would be able to support them,” Newman said. “I’m like, ‘That’s not really what I do.’”
By now, most people have heard that health-care providers tend to receive little education in nutritional science during their training. Some say this fact has become something patients like to throw at them in a knowing tone. “My doctor knows nothing about nutrition,” complained one user on the r/carnivorediet sub-Reddit, linking to a study that backs their own claims (and refutes their doctor’s) as proof. “They don’t learn about nutrition,” one patient told me. “It’s not even any fault of their own. It’s just not part of their medical training.”
They do have a point. A 2018 study found just under 14 percent of physicians felt adequately prepared to discuss nutrition with their patients. As for nurse practitioners like Newman, whom you are increasingly more likely to see than a doctor, 75 percent of the top programs failed to meet the recommended hours of nutrition training. Forty years ago, the National Academies published a 141-page screed for prospective donors on the dismal state of nutrition education in the United States, recommending a 25-hour minimum requirement. It’s considered the bare-minimum benchmark for nutrition education, and most medical schools still fail to meet it.
But there’s an obvious yet overlooked problem here, one that helps explain both providers’ reluctance to dole out dietary advice and why nutrition isn’t emphasized in most medical training programs: So much of the nutrition research their patients are asking about just isn’t very good.
“For every study that exists out there that says there’s some benefit to wine or to coffee, there’s another study that points to one of those things being problematic,” said Dr. Skyler Johnson, a researcher and oncologist at the University of Utah Huntsman Cancer Institute. Most published studies in nutrition are observational; they can find associations between diet and health but can’t pinpoint cause and effect. And most nutrition studies rely on self-reporting, or gathering data by asking people what they ate the previous day (or week or month or year, depending on the intended time frame). The obvious problem is it’s not easy to remember everything you ate, say, last Thursday. It’s also possible that, when asked to report their dietary habits in the context of a nutrition study, some people may embellish. “The only way to know what people are eating is to feed them and lock them up so they can’t cheat,” said Marion Nestle, professor emerita at New York University and a longtime critic of shoddy nutrition science.
Such studies do exist, but they’re expensive, and dietary research has historically not been well funded. According to a November 2024 report from the National Institutes of Health, from 2019 to 2023, less than 5 percent of the NIH budget went to nutrition science. That means many nutrition studies are small and short term, making them less reliable and thus more likely to be contradicted by other (similarly small and short-term) studies.
Johnson’s patients are often desperate to find something they can do to improve their chances of surviving cancer, for example. Isn’t there a supplement or particular food that could help? Sometimes they mention a study they’ve found that supports the dietary change they have in mind and are frustrated at Johnson’s skepticism. “There are just so many confounders in these nutrition studies that the data is so mixed that there’s not a clear recommendation,” he said. “I often tell my patients that I’m equally frustrated.”
Often, they bring him something they found on social media, where a simple and declarative 60-second video is more likely to capture attention than one made up of more accurate but comparatively dull caveats. Lately, Johnson’s patients want to talk about posts they’ve seen on the “Warburg effect,” named for the biochemist Otto Warburg, who observed over a century ago that cancer cells seemed to prefer consuming glucose. (“Let’s talk about the connection between sugar and cancer,” begins a Warburg-effect-themed video by a nurse practitioner with nearly 700,000 followers on TikTok. “And if you think they’re not connected — you’re wrong.”) Sometimes, Johnson’s patients who’ve seen content like this will worriedly ask him if they should adopt a ketogenic diet while undergoing treatment. “What people don’t understand is that cancer cells can use any form of energy, whether it’s from sugar or not,” Johnson said. Sugar isn’t likely the single thing that caused his patients’ cancer, and cutting it out isn’t likely the single thing that will cure it. “But they have this belief that sugar feeds cancer, so they’re cutting all sugar out of their diet,” he said. It’s not a bad idea generally to curb sugar consumption, but oncologists are wary of restrictive diets that can cause too much weight loss and negatively affect treatment. Sometimes, patients ignore his advice and go ahead with the strict diet they heard about online. (What do doctors know about nutrition, anyway?) “You could talk to any oncologist, and they will have seen people making these extreme dietary modifications,” Johnson said.
This summer, Health and Human Services Secretary Robert F. Kennedy Jr. announced an initiative urging medical schools to incorporate nutrition science into their curricula. (Kennedy and Education Secretary Linda McMahon set a deadline of September 10 for accreditors to submit detailed plans of their commitments.) But this isn’t just a MAHA cause: In September 2022, the Biden administration’s White House Conference on Hunger, Nutrition, and Health included a national strategy calling for increasing nutrition education for medical professionals. And it isn’t just an American problem, either. It is estimated that less than half of accreditation and curriculum guidance for medical education worldwide even mentions nutrition. But how can increased medical training in nutrition help if so much of the research it would be based on is flawed? And even if more doctors did dole out dietary advice, would it really be what their patients were looking for?
The problem isn’t that researchers know nothing about nutrition. It’s more that what they know is really boring. Much of the dietary advice with the best evidence to back it up sounds a lot like common sense. This summer, for example, a randomized trial that followed more than 2,000 people at risk for dementia for two years showed that the MIND diet — which stands for Mediterranean-DASH Intervention for Neurodegenerative Delay — along with other healthy behaviors like regularly exercising and socializing, led to greater improvement in cognitive performance. What foods are included in the MIND diet? Whole grains, leafy greens, and beans are a big part of it, along with limiting butter and cheese as well as fried or fast food. Not exactly surprising.
That’s just not what most people are asking their doctors about. They don’t want the basics; they’re looking for specifics. “I do completely understand why a patient wouldn’t want to pay a co-pay to come see me and me be like, ‘Uh, eat more kale?’” Newman said. Dr. Dariush Mozaffarian, a cardiologist and the director of the Food Is Medicine Institute at Tufts University, echoed this: “Patients want to know, ‘Look, I have joint pain. What food is going to help with my joint pain?’” Mozaffarian fields these kinds of questions in his social life, too: Earlier this year, a friend with a severe autoimmune condition started grilling him about broccoli, of all things. This person had come across research suggesting a particular chemical found in broccoli might be a natural way to improve immune-system functioning. Could eating more broccoli help with an autoimmune condition? “That kind of science we don’t have,” Mozaffarian told his friend.
If most people want nutrition science to deliver hyperspecific advice about a single food or nutrient, that’s in part because of the way journalists have tended to report on the field. For 16 years, health-care journalist Gary Schwitzer logged examples of these stories on his site Health News Review, which critiqued the way journalists reported on health. Nutrition studies were a frequent target, and when we spoke this summer, Schwitzer dug through the archives to pull up a couple of examples. “Hold on to your chair here,” he said, referring to a 2017 New York Times story about a study on walnuts and weight loss. It’s a tiny study, following just nine people for ten days, and the setup is an odd one involving brain scans and pictures of either cake or veggies or rocks or trees. “If we told stories that way — because this was not well explained in the story — you would lose readership. You’d lose following. You would be ridiculed, I believe,” he said.
Last fall, Schwitzer was annoyed out of retirement when his wife sent him a story about a study on taking vitamin K for leg cramps. “I’m probably only two or three paragraphs down, and I just rise up and I’m pissed. This is just garbage,” he said. Within 24 hours, he launched a Substack, and he has published around 90 posts since. He said fewer journalists lately seem to be doing study-of-the-day stories; instead, health influencers on TikTok or podcasts have stepped in. To be fair, it turns out this way of understanding nutrition science — drawing a straight line from this specific nutrient to this specific health outcome — can be traced back to the way the research was originally conducted. The discipline is still less than 100 years old (the first vitamin was isolated in 1926), and its earliest days were focused on diseases derived from vitamin deficiency, like scurvy. “It’s a very reductionist approach, breaking down food into nutrients,” Mozaffarian said.
But it worked: A number of then-endemic diseases were successfully treated with dietary interventions. “So when we started studying chronic diseases around 1980, that same reductionist approach was taken,” said Mozaffarian, who in 2018 co-authored a paper in the BMJ tracing the history of modern nutrition science. By that time, fat was widely believed to be linked to heart disease, an association that has since been upended by multiple studies, including a huge randomized trial in 2006 showing that women who ate a low-fat diet were just as likely to develop heart disease as women who ate a diet higher in fat. The original association between fat and heart disease could be, as some have argued, the result of the sugar industry’s influence. But the studies were designed that way in the first place because of this precedence of pinning a disease on a single nutrient, Mozaffarian argues.
Some newer research is beginning to show that addressing chronic disease is more about understanding the effect of dietary patterns (like that MIND-diet study) as well as food processing. In a 2019 study, NIH scientists really did manage to lock up a bunch of study volunteers and control what they ate. They admitted 20 participants to the NIH Clinical Center and kept them there for a month, randomly assigning half to a diet of minimally processed food and the other half to a diet of ultraprocessed foods. Those who ate the ultraprocessed foods gained more weight on average at the end of the trial; they also consumed more calories per meal. “To address chronic disease in this country, diet is absolutely core — and it’s not about a single nutrient,” Mozaffarian said. “It’s a combination of complex things that are in minimally processed foods that we’re just starting to understand.”
Yet at the doctor’s office, all of this so far still means providers are stuck making recommendations that can feel unsatisfyingly vague or even obvious to their patients. Never mind that most Americans don’t actually do the obvious. “That’s, to me, where we really have to move the field — how do we change our systems and our policies and our food environment to make that easier?” Mozaffarian said. Newman added, “They don’t do the basic things, but they’re like, ‘Oh, but you know what? It’s $74 a month for this microgreen adaptogenic supplement I can get at the Costco. That’s going to fix it.’” A dismissive way to think about the allure of superfoods is that people want a quick fix, which is no doubt often true. But people also want certainty and simplicity, particularly when it comes to terrifying health diagnoses. “They want some sense of control over their cancer,” Johnson said of his patients who obsess over finding the single nutrient or supplement that will deliver them. They’re looking for something to do. “It makes them feel like an active participant in their treatment,” he said.
An underreported recent finding is that medical schools do address nutrition, at least for the newest generation of physicians. In a survey of med schools released this August by the Association of American Medical Colleges, 100 percent of respondents reported covering nutrition in some form, up from 89 percent five years ago. Fewer than half of those respondents required their students to take multiple nutrition courses, and just 17 percent integrated nutrition information across all years of training. But it’s not true that doctors are taught nothing about nutrition. “It was always exercise and diet — that was the first recommendation you would make for somebody who had, say, prediabetes,” Johnson recalled of his own courses in primary care.
Even if primary-care providers could answer the kinds of questions their patients throw at them, who has the time? Newman sees patients every 15 to 30 minutes; national surveys suggest physicians see 20 patients a day on average. Already, primary-care providers would need an estimated 26.7 hours a day to follow all the recommended care guidelines. “The single overriding issue in all of this is that they don’t make any money if they spend any time on nutrition,” Nestle said. “Even if you knew everything there was to know about it, you can’t do it and you’re not going to be paid for it. The best they can do is find a dietician who’s really good and refer their patients.” (The term registered dietician nutritionist, or RDN, is often used interchangeably with nutritionist, but they’re not the same thing. Becoming an RDN requires a graduate degree along with a supervised practice program and an exam. But many states, including California and New York, have little to no regulatory restrictions around who can call themselves a nutritionist.) True, a registered dietician may provide much of the same advice that can be found on an information sheet handed out by a general practitioner. But, best-case scenario, they’ll be able to spend more time talking to the patient and understanding their lifestyle and preferences, which they can then use to craft a dietary plan the patient will actually follow. “You want somebody who knows how to work with people from where they are, who isn’t going to impose ridiculous stuff about calcium and vitamin B6 and all that other stuff — just talking about food,” Nestle said.
Meanwhile, the perception that providers know nothing about nutrition can itself be detrimental. If people don’t think their doctors are knowledgeable about diet, they won’t consult them when they decide to make a change. Johnson’s cancer patients, for example, need to maintain a high calorie intake to keep making the immune cells that are potentially impacted by chemotherapy. In extreme cases, he has had to stop the treatment to address a patient’s rapid weight loss — sometimes with a feeding tube. “It’s rare,” he said, “but it is a real phenomenon.” In part because of what he has witnessed, he’s lukewarm about the idea of physicians getting more nutrition training. “Do I wish we learned more about nutrition? Yes and no,” Johnson said. “I think it should be more emphasized.” Then again, what’s the use, he wondered, if the findings he’d have studied back then were based on small or unreliable datasets?
Dr. John Ioannidis, a professor of medicine at Stanford and a vocal critic of bad nutrition science, suggested an alternative: Instead of loading physicians-in-training up with nutrition courses, maybe spend some of that time hammering home how to properly digest a medical study. “By the time they graduate, the evidence may be different. And by the time they finish their residency, it will be, again, completely different,” he said. Evidence evolves over time, but by training physicians to better assess it, they’ll be better equipped to follow it as it changes. But that still lands providers in the unenviable position of fielding their patients’ questions about the flashy new research they heard about on TikTok and trying to turn the conversation back to sensible leafy greens. “We’d be learning about, you know, apples,” Newman said. Meanwhile, her patients are asking about ashwagandha. “It’s not what they’re looking for.”
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