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What the Heck Should We Eat? with Dr. Mark Hyman


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With flip-flopping dietary advice coming from every direction, it's hard to keep track of what we should or shouldn't eat. Dr. Mark Hyman set out to make deciphering the information easier with his new book: Food: What the Heck Should I Eat? Today, we chat with Dr. Mark Hyman and not only discuss what you should eat, but we also the "why" and the "how", and various ways you can sift through the changing and conflicting overload of dietary information.

Revolution Health Radio podcast, Chris Kresser

In this episode, we discuss:

  • Why are people so confused about what to eat?
  • Food is medicine
  • Transitioning from vegetarian to meat-eater
  • “It’s not the cow, it’s the how” and studies that don’t prove cause and effect
  • The false demonization of meat, saturated fat, and cholesterol
  • The Paleo template and avoiding strict diet dogma
  • Cellular and acellular carbohydrates

Show notes:

Hey, everybody, Chris Kresser here. Welcome to another episode of Revolution Health Radio. This week I’m very excited to welcome back Dr. Mark Hyman to the show. Dr. Hyman is a practicing family physician, a 10-time #1 New York Times best-selling author, and an internationally recognized leader, speaker, educator, and advocate in the field of Functional Medicine. He’s the Pritzker Foundation Chair in Functional Medicine at the Cleveland Clinic Lerner College of Medicine and the Director of the Cleveland Clinic Center for Functional Medicine. He’s also founder and director of the UltraWellness Center, chairman of the Institute for Functional Medicine, medical editor of HuffPost, and a regular medical contributor in the media for CBS This Morning, Good Morning America, CNN, The Dr. Oz Show, and more.

I met Mark personally a few years ago; of course, I’ve known about his work for many years. There is really no one else who has done as much to advance Functional Medicine as Dr. Hyman, and over the last couple of years I have gotten to know him personally and really enjoy his balanced, nuanced approach and everything he does as an advocate for Functional Medicine and nutrition in the field. So, I’m really excited to welcome Mark back to talk about his most recent book: Food: What the Heck Should I Eat? It’s a great title, and I think a lot of people actually have that question at this point. We’re so overwhelmed with so much conflicting, contradictory information, and I think a lot of people have just thrown up their hands and really don’t know what to eat, so that’s what we’re going to talk about in this episode. I hope you enjoy it as much as I did. Let’s dive in.

Chris Kresser: Mark, it’s such a pleasure to have you back. Thanks for joining us again.

Mark Hyman: Of course. It’s always so great to talk to you, Chris.

Chris: Before we jump in and start talking about food, which is what we’re going to be mostly talking about today, I just want to kind of get some updates from you. It’s been a while since we’ve chatted, and especially with you, there’s never a dull moment. So what’s been going on in your world and how are things going at Cleveland Clinic Center for Functional Medicine and what’s new in your world?

Mark: So many things. I got married.

Chris: Congratulations again.

Mark: Thank you. I was super sick and had to use the magic of Functional Medicine to fix myself and learn new things and launch A Broken Brain documentary online, and it’s a lot of stuff going on. We’re excited about my new book, Food: What the Heck Should I Eat? which is, I guess, what we’re talking about today, and it’s really been a labor of love, and it’s one of my favorite books that I’ve written out of 14. I think this is my favorite because it just gives people what they need, and it’s so difficult for people knowing how to sort through all the confusing, often conflicting, advice about what is healthy nutrition.

Wondering what the heck you should eat and why there are so many conflicting opinions? Dr. Mark Hyman shares his answers in his new book

Why Are People so Confused about What to Eat?

Chris: Yes. Most people on the street now, I think, are feeling pretty overwhelmed at this point, and they don’t really know who to trust or what to believe. For many years it was like eggs—I think there are some jokes about this, like “eggs are good, eggs are bad, eggs are good, eggs are bad,” back and forth, and I think with enough of that it’s kind of, people do start to tune out and they don’t really believe anything, and it is left to their own devices. So what’s the deal? What’s your take on why this has been so confusing and conflicted?

Mark: Well, it’s a sort of a whole conspiracy of actions from a whole different set of sectors. It makes the consumer wonder what the heck they should eat and why there are so many conflicting opinions. One is science and nutrition are challenging because it’s hard to study what people eat. In a typical research, you give someone a drug and another group you would not give the drug and you follow them along for a year and you see what happens and you control everything else. That’s impossible with food unless you only feed them certain foods and another group you only feed other foods and you do that for 10, 20, or 30 years. Then you’re going to get useful information, but no one’s going to do that. So you have to sort of try to understand what studies show and what they don’t show. A study can prove cause and effect and one study can’t—

Chris: And people are notoriously inaccurate when they report their food intake. That’s another problem.

Mark: There’s also the bias. I mean, we’ll talk about it, but meat is a great example. Meat was deemed to be bad because it contains saturated fat. Saturated fat was thought to be bad. Saturated fat in your diet was bad, so hence meat was bad, but there is no evidence that meat was bad. There were no studies showing it was bad. It was built by association based on some pretty bad studies, and so people are confused about it. During the time that the study showed that meat was bad, it was because the people who were eating meat didn’t care about their health because everybody said meat was bad, so if you ate meat, you really weren’t concerned about your health, and you ate more calories, you weighed more, you smoked more, you drank more, you didn’t eat any fruits and vegetables, you didn’t exercise. The people who didn’t eat meat in those studies exercised, ate healthy food, fruits and vegetables, didn’t smoke, didn’t drink too much, took their vitamins. They were healthy. It wasn’t because they didn’t eat meat that they were healthier. It was because they had all these other healthy habits, and I think the reason people who ate meat got sick was because they had all these unhealthy habits. So you have to look at the context of the study.

Nutrition research is notoriously bad and there’s money in the whole problem, which is science is funded by different vehicles, one is industry and one is the government, and there’s philanthropy. Philanthropy hasn’t done a whole lot in the field of nutrition research, although that’s changing. The government funds only certain kinds of studies, which aren’t that helpful, and the food industry is funding studies that prove their products are healthy. If you look at the data, for example, on artificial sweeteners, almost 100 percent of the studies done by the food industry on their products find out they’re safe, whereas almost 100 percent of studies done by independent researchers find that they’re harmful. So you have to look at where the money is coming from, and then the third reason is the government is not producing guidelines that match the science.

If you look recently, the Congress mandated the National Academy of Sciences, which is the nation’s highest independent science group, to look at how we come up with their dietary guidelines, and they published a massive report in November, I think, October 2017, where they outlined how corrupt the process was and how unduly influenced it was by industry and how the people and the Guidelines Committee worked for the Dairy Council and other industry trade groups, and there are huge amounts of data, for example, or unsaturated fat, which really has exonerated saturated fat, but still the government recommends to not eat saturated fat. So yes, it made some progress, it said we don’t have to worry about fat anymore, yes it said we don’t have to worry about cholesterol or eggs anymore. But there’s still a lot of corruption in the guidelines, which inform all of our policies and recommendations. Then of course there are the public health and professional associations like the American Heart Association, the Academy of Nutrition and Dietetics and their funding in large part comes from the pharma and the food industries. Forty percent of the Academy of Nutrition and Dietetics funding comes from junk food industry companies.

Chris: Yes. I’ll never forget a registered dietitian that we work with told me what was served at those conferences. It was all vastly sugar. Basically, the entire table was sugar, and it was low-fat, so-called “healthy” because it’s low fat, but it’s all processed and refined sugar, basically.

Mark: Exactly. I mean I also read a big meeting in California of The Nutrition Society. There was a mandatory lunch, and the lunch was provided by McDonald’s.

Chris: Oh my God. That’s just crazy. So we’ve got these three problems—

Mark: And then there’s one more, which is the media.


Mark: —headlines and does a disservice to the consumer by latching onto various means that actually are incorrect, like the recent coconut oil. You can see where the American Heart Association said that that coconut oil was bad, and by the way, there’s not a single study that shows that. It was again built by association, which is it’s got saturated fats, saturated fats are bad, so don’t eat it. And the USA Today headline “Coconut Oil Is Not Healthy, Never Was Healthy,” and so everybody just went into a tizzy and got so confused. I know you wrote about it. I certainly wrote about it. I mean, people are confused. I did a Facebook, like there were over a million views because people are just so desperate to know what to think. All these reasons lead to a confused eater.

Chris: Yes, and that’s a big deal because food—one of the fundamental tenets of Functional Medicine is that food is medicine, and that’s how it’s different than conventional medicine, which is you go in, you have a chronic condition, generally you’re going to walk out with a prescription for a drug, maybe some vague advice about eating healthier. But in Functional Medicine, of course, we approach it differently, so I imagine that was a big impetus behind you writing this book at this time too.

Food Is Medicine

Mark: Absolutely. Food is medicine, and I was so heartened to hear that one of my friends and colleagues and you know well, Dr. Dariush Mozaffarian, who is the dean of the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University, recently was in Washington holding a hearing on food as medicine and how we need to influence policy, or this new understanding of the role of food and health and chronic disease, so I think that’s moving forward. In the meantime, people are wondering, what the heck should I eat? And then of course there are other issues besides whether it’s healthy or not. How is it affecting the environment? How is it affecting our soils, water, air, and climate change? And how do we treat animals? And all these issues are so confusing for people. So should you eat GMO or should you not? Does it matter if you eat organic or not? What about food additives? Are they very safe? Are they bad? What about processed foods? Are there any ones that you can eat? These are very confusing to people. So I’ve taken my 30 years of—well, actually probably, God it’s embarrassing to say now, 40 years of studying nutrition, oh my God, I’m old—

Chris: Fantastic.

Mark: I started in Cornell in 1979 or ’78, and it’s almost 2019, holy cow. All right. Anyway, moving on, I’ve been studying nutrition that long, and the first book I read was Nutrition Against Disease, by Roger Williams, of how food can be used to actually heal chronic illness. In that time I really swung back and forth from being vegetarian and vegan to being low fat to being high fat to being Paleo, all the way in between, experimenting, and I’ve done that with my patients. I’ve probably read, like you, probably over 10,000 papers on nutrition and I’ve treated over 10,000 patients over 30 years, and I’ve seen the results of people doing different diets in real life looking at all their biochemistry and hormonal regulation, their metabolism, their other health conditions, and so this isn’t just a theoretical book. This isn’t just based on some scanning of literature and trying to put something into something that makes sense. This is a combination of my own experimentation, my work with patients, reviewing literature, studying nutrition for 40 years and coming up with just common sense, not extreme, in a way to eat that actually follows the guidelines of most of the sort of trends out there. In other words, you’ve got vegan, you’ve got Paleo, you got raw food, you got keto, you got high fat, low fat, high carb, low carb, it’s pretty crazy for a consumer, what should they do. So I’ve taken all that and tried to synthesize it in really practical ways. It’s not about individual nutrients, and you and I both write about those things. What about omega-6 fats? What about zinc?

But at the end of the day, people eat food. They eat meat, they eat vegetables, they eat chicken, really, and so in my book I go through each major food category, meat, poultry and eggs, dairy, nuts, seeds, beans, grains, vegetables, fruit, drinks, beverages, sweeteners, and come up with what do we know, what do we don’t know, and combined with sort of common sense and evolutionary biology, which is what you call ancestral nutrition, what makes sense. So that’s really where I sort of came up with this idea of the book is, how do we sift through all that and give people a guide? It’s sort of like a user’s guide to eating.

Chris: Yes, absolutely. It’s so needed and it’s something that shouldn’t be that complicated, but as you’ve pointed out, has gotten really complicated. It has, I think, also taken people away from their own intuitive sense of what’s right for them, which is a whole other topic. But I want to talk a little bit more about meat because that’s obviously, if we were to think of one thing that maybe causes more conflict and sometimes even violent conflicts from people who think we should eat it versus we shouldn’t eat it. I know this is an area where you’ve now changed, as you said, you’ve shifted. Both of us have been vegan in the past. I was a macrobiotic vegan at one point and then a vegetarian, and both of us now eat meat. What led you to make that transition yourself, and then what should we be looking at from your perspective now in terms of meat consumption?

Transitioning from Vegetarian to Meat-Eater

Mark: It is the big rallying point for controversy, and I want live to be 120. I have a young wife, maybe 140 if I can get there, and I don’t want to do anything that’s going to jeopardize that. Just a human being, I want to know, and a scientist and doctor, I have the ability to figure that out, and I lock myself in a room with a stack of the best papers on meat and research on meat that were about three feet high for a week in a hotel room so I wouldn’t be distracted, and I just read it all. Then I synthesized it and I realized there are really three main issues around meat.

One is moral, and I have patients who are Buddhist monks, and if they don’t want to eat animals, that’s okay. We can work around that part. Then there’s more around how we treat our animals, and that’s a fair concern around how we humanely can raise animals, and I want to talk about that. Then there’s the environmental issue, which is very real, and our CAFO system of agriculture, confined feeding operations, these are factory farms using a lot of industrial inputs from oil through fossil fuels, through fertilizers, pesticides, herbicides to grow the food; enormous amounts of water through irrigation that depletes our aquifers; the runoff from the fertilizers damages the waterways, it causes dead zones and kills all the marine life; to the effect of climate change from the methane in the way we produce and grow food; and the depletion of our soils, which leads to the inability of the soils to sequester carbon; to our depletion of our aquifers from irrigation for the water, which leads to droughts, which is why we have this whole problem. So those are all real issues, and yet it’s not about meat or no meat, it’s how we raise the meat.

There’s a movement of regenerative agriculture, which is fascinating, which is using animals to help build soil, which then sequesters carbon, retains water, and raises animals that have much higher-quality meat and don’t contribute to climate change and actually help reverse climate change. They’re humanely raised and actually are a part of the natural agricultural cycle. Even organic agriculture, feeding a ton of plants that are grown with conventional tilling, organic agriculture, you’re doing a little bit better avoiding pesticides, but you’re not actually helping the soil, and you’re contributing to climate change, and by the way, most plants are not vegetarians. Most plants are carnivores because organic food is fertilized with bone meal and where else would that come from?

“It’s Not the Cow, It’s the How” and Studies That Don’t Prove Cause and Effect

Chris: And a lot of animals are killed in that style of agriculture too. They are smaller animals, but then you start getting into the question of, is the life a rodent any worth less than a life of an herbivore? There’s a film that I’m supporting, a friend and colleague of mine is making, called Kale vs. Cow: The Case for Better Meat. She sent me a t-shirt that I love with the tagline, “It’s not the cow, it’s the how.”

Mark: That’s right, that’s right. That’s exactly what I’m talking


Chris: That sums it up. It’s not the cow, it’s the how,

Mark: There’s a book coming out, it just came out, called Kiss the Ground, and a movie, a documentary, coming out as well, which talks about this whole movement of regenerative agriculture. So the whole issue of environmental issues can be addressed. We have 60 million bison that were in this continent that we’re raising and they built literally tens of feet of topsoil over a millennia, who knows how long they were here, and we have 60 million. It’s not the fact that we have so many cows, it’s how they were raised and what they do. The bison actually were contributing to climate change because of the way that they were roaming and grazing and restoring soils. So that’s a whole issue, so I think environmental issues are right. I don’t think anybody should eat CAFO meat, both for their health and for the environment.

So then the third issue other than moral, environmental, is health. And then the question becomes what does the data show about the effect of meat on our health? And when I began to look at that, it was all over the place. There were large studies that showed it was harmful, studies have shown it’s helpful. If we look at the studies that showed the population studies, these are what we call observation or population studies. They don’t prove cause and effect, what they do is they give people a food questionnaire every year and they ask them what they ate and see who died from what, and then they correlate these things, but correlation isn’t causation. I wake up every morning and the sun comes up. I had nothing to do with the sun coming up, right?

Chris: Don’t be modest.

Mark: I could do a study of women over 55 who have sex and I would conclude 100 percent of the time that sex never leads to pregnancy. It’s wrong but it’s right as far as the study goes, so I think we have to understand that. Now when you look at the data that, you find that, gosh, the meat eaters in those studies, which were done in a time when meat was evil, didn’t give a crap about their health. Like I said, they ate more calories per day, they smoked more, they drank more, they didn’t exercise, they didn’t eat fruits and vegetables, so their results are confounded and the people who didn’t eat meat were trying to be healthy. It wasn’t that the meat was the problem, and of course they’re eating CAFO meat. And then there are studies that look at vegetarians and meat eaters who shop at health food stores who would presumably have a healthy diet, so eating meat in the context of a healthy diet is a very good thing. For example, today I had a big salad with arugula, pumpkin seeds, avocados, fennel, and cherry tomatoes, and I had a few slices of grass-fed beef with it. That’s what I call a “Pegan” diet, which is kind of a joke between Paleo and vegan, but it’s essentially eating meat in the context of an otherwise healthy diet. The risk was reduced at half for both of those groups. And then you look at interventional studies, which is a more reliable type of study, where you actually give people, let’s say, a Paleo diet. I just saw an article published today about women who eat Paleo who are overweight have much more weight reduction and health benefits than those who don’t, and so you have to look at the interventional studies. Typically, the Paleo diet is a little bit higher in fat, but there was another study published just recently where they looked at a free, unlimited-calorie diet that’s high in fat and low in carbs and starch versus a diet that was a restricted, low-calorie diet that’s high in carbs and low in fat. After a year, the people who could eat as much as they want and includes lots of fat lost far more weight. This article was just published, I think, today. It was called “Paleolithic diet healthier for overweight women,” looking at the risk factors for diabetes and heart disease. It was done in Sweden, and they found that it made a huge, huge benefit through a low-glycemic diet. That was just published, I think, yesterday.

Chris: Yes, and there are many others like it for blood sugar issues and metabolic problems, weight loss, changes in waist circumference, etc.

Mark: I’ve seen an interesting study where it looked at—there was a study of wagyu beef, which is like feedlot beef, versus kangaroo meat. In the wagyu beef, they looked at biomarkers and people who eat them, and they found there were a lot of inflammatory biomarkers, gene inflammations linked to every known chronic disease, and the people who ate the kangaroo lowered their inflammatory biomarkers. So it’s not only meat, it’s the quality of the meat that you eat and what it contains. Grass-fed meat has much higher levels of omega-3 fats; higher levels of antioxidants like catalase, glutathione; and it has much higher levels of minerals and vitamins. So it’s a very different food than you’re feeding a feedlot beef. If you don’t have enough money and you can’t eat a grass-fed cow, even sort of regular meat, I think, is a better option than eating a ton of carbs. We vilified meat because of the saturated fat. I think that was really a mistake and I can go deeply into that, but that was another reason why we thought meat was bad. I’ve talked about a lot of this on your show, but saturated fat isn’t the bogeyman we thought it was. In fact, the saturated fat in meat doesn’t even raise your cholesterol. It’s stearic acid. So it’s not even the one that’s a bad one. And the last issue is cancer. What about meat and cancer? I think we heard a lot of headlines last year about the WHO saying that meat causes cancer, processed meat in particular. It was true they found a correlation, not causation, correlation by 20 percent increase in the risk of colon cancer for people who ate a lot of processed meat like deli meats, hot dogs, and things. But when you look at the data, given the statistics can be manipulated … so Roger Williams says, “There’s liars, there’s damn liars, and there’s statisticians.” When you look at the statistics, a 20 percent increase in colon cancer sounds terrible. What they really found was that was a relative increase. The risk went from a background of the population of 5 percent chance of getting colon cancer to 6 percent. That’s a one percent absolute increase and that’s only if you ate four pieces of bacon every day your whole life, and I’m not going to do that, only if you’re eating a ton of processed meats, but they can be part of our diet, especially if they’re raised sustainably and humanely and so forth. So I think that the whole issue around cancer is kind of a little bit overblown.

Chris: Yes. I would agree with you, and I’ve looked into that in more depth than I ever thought I would just because I know it’s such a rabbit hole, and it’s not easy to draw conclusions by just scanning a few studies. You really have to dig in. You have to look at the data and the tables and not even pay attention to the researcher’s own conclusions, which are sometimes in conflict with their data.

Mark: It’s true.

Chris: It’s deep. You really have to look at it.

Mark: It’s true. I read a study in JAMA once where they actually analyzed the abstracts and compared it to the data published in the study, and 50 percent of the time the abstract conclusions didn’t match the study results.

Chris: Right.

Mark: That was like, oh my God.

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The False Demonization of Meat, Saturated Fat and Cholesterol

Chris: Do you remember that paper in The New England Journal of Medicine that suggested that a Mediterranean diet was better than the normal diet, and the implication was that red meat was bad, but when you looked at the tables you saw that the Mediterranean diet people ate just as much red meat as the control group. That stuff happens all the time, and unless you’re really diving in and looking at that level of detail, if you’re just, if you’re just reading abstracts, or even worse, the media summary of the study, you’re not going to get the real story. Speaking of the real story, meat has caused a lot of confusion, but I think cholesterol has got to be right up there. I mean, that’s how I got my start. My blog was The Healthy Skeptic. I started writing about the relationship between cholesterol and heart disease many, many years ago now, and I think most people who are above the age of 35 or 40 have grown up with that just absolutely drilled into their head that cholesterol is bad. If you eat cholesterol, it’s going to clog your arteries. It’s kind of the junk in the pipe metaphor. Cholesterol is junk or gunk, and you eat it and it clogs your arteries and you get a heart attack. Why then did the US, for the first time ever, remove the restriction on cholesterol in the diet?

Mark: Yes, it’s sort of sloppy thinking. We have conclusions from insufficient evidence or no evidence, it’s just based on some theory. It’s just like we thought, oh, you eat fat, calories, carbs, and protein so it’s going to make you fatter, so to lose weight you eat low fat because that makes you fat, and it seems like a logical conclusion. It looks the same on your body. It’s got the same name, it seems logical. Just like cholesterol, you’ve got cholesterol deposits in your arteries so the cholesterol is going to cause a problem. It turns out neither of those things is true. Heart disease is actually hormonal and an immune problem, not so much a plumbing problem, and our hormones that go awry are insulin, which drives bad types of cholesterol. Eating carbs and sugar actually causes far more harm than eating fat. In fact, that may actually protect your cholesterol in many ways. And so, we kind of got the whole story wrong, and so the government finally said, “Oops, we really didn’t look at the data. We just sort of assumed that it was bad and then when we kind of looked at the data; it really wasn’t bad, so we’re sorry.” Thirty-five years of egg-white omelets—

Chris: Sorry you had to suffer through those.

Mark: Oops, oops. The way they did it was so funny. They were like, “It’s no longer a nutritive concern.” And I thought that was hysterical, instead of like really owning up to the fact that they were wrong.

Chris: Right. And even talking about the benefits of foods like egg yolks and how nutrient dense they are and that they are a rich source of choline, which is hard to find elsewhere in the diet. I think that they wanted to save face, and so if they made a big splashy announcement, people would be like, “Oh, man, we’re not going to listen to you.”

Mark: Yes. I think the whole cholesterol issue is much more complicated around fat, diet, and carbs, and it turns out for most people … and there’s a lot of genetic diversity in how people handle different food, whether it’s carbohydrates or fats, and there are different responses that you can have with the same diet in different people, and I’ve seen this as a clinician, so it’s humbling. It’s not like, “Oh, we’ll just eat this way.” You’re a practicing physician, I’m a practicing physician, you get humbled by saying, “Oh shoot. I thought this was going to be good, but it actually made this person worse. I don’t understand what’s going on here.” We’re learning more about the genetic diversity around how we respond to different things. But for the most part, Americans, 70 percent of us are overweight, and for most of those people, it’s insulin resistance, and insulin resistance is actually made better by fat and improves the quality of cholesterol. I just saw someone today. I looked at their lipids. I was blown away. Their HDL went from 36 to 60 by switching them from a high-carb to a high-fat diet and saturated fat. I’m like, “Whoa. This is impressive.” And their triglycerides plummeted and their LDL went up a little bit, but the ratio improved. The quality and the size improved. They went from having a lot of small particles to having none. I was like, “Okay, this is interesting.” I think you and I have a unique perspective because a lot of people talking about this aren’t actually doing it. I think it changes how you think about it because you go, “I think this is the truth,” and you try, and it doesn’t work, and you go, “Oh—”


Chris: Yes. What happens when someone goes on a keto diet and their LDL particle number goes up to 3,500? Is that necessarily a good thing? Maybe they lose weight and their blood sugar improves, but their LDL-P goes above 3,000, then that person’s going to require a more nuanced approach. It’s not just simple heuristics that we can rely on in those cases. I agree. I mean, that’s what you get when you’re a clinician and you’re working on the front lines. You actually see that, and so it becomes a lot more difficult to stick to a certain belief system when you see evidence to the contrary every day.

Mark: I think you just said something really important, which is that a lot of people who are giving advice have belief systems, and this is not about your beliefs. This is about what the data show and what patients actually manifest in response to different things. Here are a lot of people who built their careers on a certain dogma, whether it’s low fat or vegan. I had a very close friend who’s built a career on being a vegan, and she said, “Mark, don’t tell anybody this, but I had started animal protein because I was not feeling well and I was unhealthy. I can’t say it in public.” I’m like, “Listen, I’m going to change my mind.” If you look at my books from 10 to 15 years ago, I was recommending low-saturated-fat diets because that’s what I thought the data showed, and I think as I have evolved, I’ve learned more and more, I think the data has improved, I changed my mind, because I want to know what the truth is. I’m not stuck to a particular belief or dogma.

The Paleo Template and Avoiding Strict Diet Dogma

Chris: Yes. And I think that’s so important. It’s the way that we can serve our patients and just the community at large by being willing to admit we’re wrong. I mean, that’s a core part of science, is proceeding from the assumption that we are wrong. We’re going to create some hope, some ideas, and then we’re going to test them out and see if they work. I mean, this is probably a good segue to talk about grains and beans and dairy. For me, that was something where I kind of diverged from the Paleo community very early on, and for folks who’ve read my first book, I called it more of a Paleo template because when I looked at the research on grains, beans, and dairy, I saw, kind of like fat, it was complicated. There are some situations where I think people should be avoiding beans, dairy, and grains pretty strictly, and there are other situations where if those are consumed in moderate amounts in the context of a low-nutrient-dense diet with meat, fish, fruits, and vegetables, that it’s fine. I know you addressed this in your book as well. So I’m curious to know where you’ve come down on this issue.

Mark: Yes. You call it Paleo template, I call it Pegan. It was total spoof. It’s just a joke I made up when I was at a conference.

Chris: It’s a great term.

Mark: I was on a panel with Joel Kahn, who is kind of a milk and vegan cardiologist, low fat, and Frank Lipman, who is a Paleo functional doc—

Chris: Was that the Mind, Body—

Mark: Yes. It was Mind, Body—


Mark: You were there.

Chris: I remember that. Yes, yes. I was there for the genesis.

Mark: You were. It’s true. It was a total joke. I’m like, you were Paleo, you were vegan, I was Pegan, and then I went home, I started thinking about there’s more in common than there are differences. I think setting up these extreme, hard-and-fast rules is a problem. Some people can’t tolerate dairy, but the question is, which dairy? Is it factory farm, hybridized cows which have high levels of hormones and high levels of A1 casein, which is inflammatory, is it goat milk, some milk in cow or grass-fed meat? This is a lot of—


Mark: Right. So I think you’re right and I think that’s in the book Food: What the Heck Should I Eat? This is sort of where I take the middle ground and go, okay, of all the foods, we’re highly adaptable beings. We can be all sorts of different diets. But you and I know if you’re eating a healthy diet, you’re including a lot of variety of foods; as long as you’re choosing high-quality foods, many people can tolerate a lot of diversity. But you and I treat very sick people, and they might need to be more aggressive with restricting things like dairy, gluten, different grains, or beans, and I think that’s really looking at within each category what should we be eating. Let’s take grains, for example. Your grains are relatively new from an evolution point of view. We’ve been able to eat them and to survive, but there’s evidence that our body has shrunk, and our health is not as good once we started eating grains, from an agricultural point of view, but the grains now that we eat are problematic. Most of the grains that are out there are wheat, corn, and rice. Wheat has been hybridized, so it’s not the wheat of our ancestors. It’s got much higher levels or something called amylopectin A, which is a very starchy, high superstarch, so it raises your blood sugar more than table sugar. It’s bred in a way to make it resistant to drought and different things, and it’s called dwarf wheat, and the guy who invented it won a Nobel prize, but there are problems with it. When you breed plants, you combine genes. Unlike humans, where you get one copy from your mom, one copy from your dad, you get 46 chromosomes, you get 23 from each, you get 46 yourself, in plants, you get like 46 plus 46 that’s 92. And when you have genes, you make proteins, and those proteins in the wheat are gliadin proteins, some of them. They are the ones in dwarf wheat which are much more likely to cause inflammation, leaky gut, which is why we’re seeing so much more gluten sensitivity. If you’re going to eat wheat, maybe you want to eat heirloom wheat like einkorn. If you’re going to eat grains, maybe you want to eat kind of non-grain grains like buckwheat, quinoa, or things like teff that are a little bit different but may also be better tolerated and they’re less likely to be GMO or hybridized. So I think we have to be smart about what we’re eating. It’s not a categorical no or yes, but it depends on what’s going on.

Chris: Absolutely. And, I mean, at the risk of pointing out the obvious, the biggest difference in terms of how we’re eating grains versus even our agricultural ancestors is most people are eating them in the form of grain-based desserts. They have a lot of sugar. I mean, the top six foods in the American diet are grain-based desserts, bread, pizza, alcohol, chicken dishes, primarily fried chicken dishes, and I might be missing one here, I’m spacing out. But if you look at what the grains are in those, we’re not talking about someone eating a bowl of quinoa with their salad. We’re talking about someone eating highly processed and refined grains that have sugar added to them in most cases, so that’s a totally, totally different thing.

Cellular and Acellular Carbohydrates

Mark: And even whole-grain flours like brown rice flour or quinoa flour, those can be problematic because you’re increasing the surface area of the food and you’re increasing its ability to raise your blood sugar. It is very different than if you eat the whole grain.

Chris: This is a concept of cellular and acellular carbohydrates. When all of that surface area is exposed, that can really feed the bad bacteria in your gut, whereas when the cells are still intact, that’s more of a traditional way of eating them, and it’s better for the good bugs in our gut. We’re learning so much. The good news is it’s a lot simpler, and that’s what I love about your book Food: What the Heck What Should I Eat? It’s really simplifying things that have been made to be too complicated, but at the same time it’s not oversimplifying because as we pointed out throughout the conversation, it’s not black or white in every different situation.

Mark: Exactly, exactly. And I think that the way I have designed the book is really very practical. It’s like, what we know, what we don’t know, and what does the science say, and I wanted … like, 10 things you need to know about grains. One, we don’t need to eat them at all because we didn’t evolve in them, and we can live happily without them. Flour equals sugar. If you are eating flour, and whether it’s whole grain or not, it’s just like having sugar. Gluten is a problem, and I explain why and why the grains we’re eating now aren’t the grains our grandparents ate, then why gluten-free food isn’t necessarily good for you and why you should be a “cereal-killer”, why oatmeal is not healthy, what’s wrong with corn, and why your rice may not be so good, and what grains are okay. And then I go through exactly where you are regarding the healthy grains. What are they? How much should you eat? I mean, there are some people advocating that we eat two cups of grains a day and two cups of beans, and that might be a problem. I talk about minimizing these things and even meat, not having a 16-ounce steak but having four ounces or six ounces. I think that that’s a very different kind of diet than we’re typically eating.

Chris: Yes. Well, I’m excited about this book. I think it’s been a long time coming, and I don’t know how you find the time to write these 14 books with everything else that you’re doing, but I’m grateful that you do because I think it’s going to help a lot of people, especially this one. I think it’s just a perfect topic. It’s the perfect time for it because, especially with social media, blogs, and summits, people are kind of overloaded with information. It’s not a lack of information, it’s too much, and just not being able to make sense of it, so I think this book is perfectly timed.

Mark: Thank you, Chris. I try to make it really simple to use, common sense, accessible, and people can just pick up and read any chapter. If they want to know about grains, they can read that. If they want to know about dairy, they can read about that, or meat. And then they can know what to do, and there are really great resources in there. If you’re going to eat meat, where should you find it? How do you get it for cheaper? What are the things you look for? Each category—what about vegetables? There are vegetables we shouldn’t be really eating that much of. For example, raw button mushrooms or alfalfa sprouts may have toxins and cancer-causing things in them. So how do you know in each category what you should and shouldn’t eat? And I also included the environmental considerations and even the political considerations. We think avocados are awesome, but Mexico, if you’re trying to live a life that doesn’t support harming people or nature, they have huge amounts of land and a lot of the avocado farms are actually controlled by drug cartels, the workers are mistreated, and it’s a mess. So these are what we call blood avocados, like they’re blood diamonds, they’re blood avocados, so maybe you should get them in California instead. That’s really the way I try to make it all clear and allow people to sort of choose for themselves what makes sense.

Chris: And that’s what it’s about. So this comes out … I’ve heard a couple different things, the 28th or 27th?

Mark: The 27th.

Chris: Okay, the 27th.  Okay, I think this podcast will be coming out either just before that or maybe even on that same day, so you can either preorder on Amazon or order it  if it’s the 27th when this comes out, and it’s going to be available in all bookstores, everywhere books are sold. Anything else you want to let us know about?

Mark: Yes. You can go to FoodTheBook.com, and I’m giving away free chapters. I’ve got free cooking videos on there, “The Four Big Lies and Myths That We’ve Been Exposed To” video there, so I have a lot of free content if you are looking to get familiar with what the book’s about and also getting a lot of value without actually having to buy the book, but of course I want you to buy the book, so it’s FoodTheBook.com. It’s one of those things that should be on everybody’s coffee table, in everybody’s bathroom, in everybody’s kitchen so they know what to do, take it with them shopping. There is even a great shopping guide of … here’s—because at the end of each chapter I go, eat this, don’t eat that. If you’re going to eat grains, here are the grains to eat, don’t eat these. If you’re going to eat meat, here’s the meat to eat, don’t eat these. It’s really really simple and clear.

Chris: It’s a really good book to gift to people too, like friends or family members who are maybe just totally overwhelmed, which is a lot of people that I come across at this point, and it’s such a good kind of summary and overview of all of these topics that we’ve been talking about, which are really the most important ones when it comes down to just sitting down and like, what am I going to eat? What should I buy when I go to the store? It really does boil down to that. Thanks for writing this book, Mark, and getting it out there and for coming back to talk to us, and we look forward to the next time.

Mark: Yes, it’s great. I’m looking forward to it. The book in the UK is being called WTF Should I Eat? And it’s got a different cover. They thought “What the heck” was too mild.

Chris: Those are the people across the pond. It’s always interesting to see how those differences shake out. So those of you, I have actually a pretty big audience in the UK, so it’s WTF Should I Eat?

Mark: Food: WTF Should I Eat?

Chris: Yes. Cool. All right. Well, thanks again, Mark.

Mark: All right, Chris. Thank you.

Chris: We’ll have you back soon, take care.

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  1. I live with Multiple Sclerosis and SIBO and have not had a quality of life for quite some time. I agree about functional medicine and using food as medicine. But I am on Medicare with no secondary insurance. I can’t afford to pay out of pocket for a functional medicine doctor. Any suggestions? Please help. Living in pain, cramping and not walking well is not a fun life at all…