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The Joe Rogan ExperienceThe Joe Rogan Experience

Joe Rogan Experience #1175 - Chris Kresser & Dr. Joel Kahn

Chris Kresser, M.S., L.Ac is a globally recognized leader in the fields of ancestral health, Paleo nutrition, and functional and integrative medicine. Dr. Joel Kahn is one of the world’s top cardiologists and believes that plant-based nutrition is the most powerful source of preventative medicine on the planet. https://chriskresser.com/rogan https://drjoelkahn.com/joe-rogan-experience-reference-guide/

Joe RoganhostDr. Joel KahnguestChris Kresserguest
Sep 28, 20183h 47mWatch on YouTube ↗

EVERY SPOKEN WORD

  1. 0:02 – 4:39

    Meet the debaters: a preventive vegan cardiologist vs. a functional medicine clinician

    1. JR

      Five, four, three, two, one. (claps) Gentlemen, thank you very much for being here. I really appreciate it. Dr. Kahn, uh, before we get started, why don't you tell everybody what your background is. Uh, you will be representing the vegan portion of this discussion. Uh, tell people about yourself a little bit.

    2. JK

      Thank you. I feel like the head broccoli in the United States today. But I am from Motown, Motor City, badass. Uh, born and raised University of Michigan School of Medicine, summa cum laude, internal medicine training, cardiology training in Dallas, Texas. Very hard to be vegan in Dallas, but I did it in the '80s, because I've been doing this 42-year vegan.

    3. JR

      42 years?

    4. JK

      42-year vegan, thank you.

    5. JR

      That's impressive.

    6. JK

      Age 18. And then, uh, Kansas City, Missouri, another tough town to eat plants in, only the steakhouse, KC Masterpiece. Did, uh, training in stenting. I was blasting open heart attacks from 1990 on. Came back to Michigan, very active cath lab, heart attack, you're dead, I bring you back practice, 24 hours a day with great partners. And about three to four years ago, I used all these decades of plant-based medicine I've been basically bringing my family up with and teaching patients, but opened a completely preventive cardiology practice. And along the way with my wife and son, we now own three plant-based restaurants, two in Detroit, one in Austin, Texas. Write books, do TV, write blogs, teach, teach, teach. Not gonna stop till I'm 150.

    7. JR

      And-

    8. JK

      Because there's a lot of erectile dysfunction to stamp out. That's my passion.

    9. JR

      That?

    10. JK

      Oh my God, what else? What better purpose in life?

    11. JR

      Um, well, okay, we can get to that later.

    12. JK

      Heart, heart, heart, heart dise-

    13. JR

      (laughs)

    14. JK

      Heart disease is somewhere in that mix too.

    15. JR

      Okay, and, uh, if people want to read more about you, website is?

    16. JK

      Yeah, uh, D-R-J-O-E-L K-A-H-N, drjoelkahn.com.

    17. JR

      And you've written a ton of books, right? How many books?

    18. JK

      Five books.

    19. JR

      Five books.

    20. JK

      And a bunch of medical papers.

    21. JR

      Okay.

    22. JK

      And a whole lot of blogs.

    23. JR

      Awesome. And Chris?

    24. CK

      Yeah, Chris Kresser. Um, I did my undergrad at UC Berkeley, and, um, then got a Master's of Science and, um, Co-Director of the California Center for Functional Medicine, which is a functional medicine clinic in, in here in California, up in Berkeley. And, uh, I came to this from my own experience with chronic illness. I- as, as you know, Joe, got really sick, uh, back in my early 20s when I was traveling around the world, and, uh, you know, conventional medicine didn't have much to offer for me. And so, that led me on a path of trying to figure out the best approach from a diet and behavior and lifestyle perspective to heal from my own chronic illness, and then that evolved into, um, me starting to write, you know, I started a blog and a website. And then, um, wrote a couple of books and now have, uh, an organization that trains practitioners in functional medicine and also trains health coaches.

    25. JR

      And you, at one point in time, were vegan?

    26. CK

      I was a macrobiotic vegan. I was apprenticing with a macrobiotic, uh, chef. So, uh ...

    27. JR

      What's the difference between a macrobiotic vegan, for folks, and a regular vegan?

    28. CK

      Uh, it, macrobiotic is a particular philosophy, it's a particular approach that came from Japan, and, um, it's vegan, but it's, it's, you know, it's, it's heavily influenced by Japanese, uh, tradition and cuisine, and it has some kind of different beliefs than a, a typical vegan approach. So I was, uh, when I was originally studying Chinese medicine, I was working and, and apprenticing with a macrobiotic vegan chef, and we were going around cooking for people who were really ill, often people with cancer who were following a macrobiotic diet. And before that, I had been a vegetarian for quite a while as well. Wh- when I was traveling around the world and got sick, actually, I was, I was a vegetarian at that point too.

    29. JR

      And you discovered through your own personal ... What are you doing over there, buddy? (laughs)

    30. JK

      (laughs)

  2. 4:39 – 8:40

    No one-size-fits-all diet: quality, context, and “nutritionism”

    1. JR

      And that is important to discuss here, that everybody's body really is different.

    2. CK

      Yes.

    3. JR

      And different people's bodies and lifestyles, th- they're gonna have different requirements.

    4. CK

      Absolutely. I mean, I, I would say, just to start off this whole discussion, if we're trying to answer the question, what's the optimal diet for everyone, I think that's a terrible question.

    5. JR

      Yeah.

    6. JK

      Yeah.

    7. CK

      And it's an unanswerable question. Uh, w- we share a lot in common as human beings, but we have a lot of important differences too. And from the beginning, I've always argued that there's no one-size-fits-all approach when it comes to diet. Um, but I think there are some common themes, and we can- I'm sure we'll get to those later.

    8. JR

      Yeah.

    9. JK

      Yeah.

    10. CK

      Yeah.

    11. JR

      I think that's really important, right?

    12. CK

      Yeah.

    13. JK

      Yeah.

    14. JR

      It's re- it's really important to discuss-

    15. CK

      So important.

    16. JR

      ... that p- people really do have different requirements.

    17. JK

      Yeah, and I mean, we'll get in the mud a little bit as we need to, but we also, Chris and I share a lot in common. I mean, one, if we ate together, it would probably be 90% the same. We both are really respectful of what we call functional medicine, root cause medicine. I don't write scripts without thinking about the patient. He certainly doesn't do that without thinking about the entire patient. It's pretty unusual, and we're gonna represent a very small section. I, I honor what he's doing with his new book, Unconventional Medicine, the rest. You know, that is what is happening throughout medicine, um, and it's necessary 'cause it just, we're- we're just running out of dollars and, and health when we're just pushing pills and not even asking a person what they eat, how they sleep, you know.

    18. JR

      Yeah.

    19. JK

      The whole thing.

    20. JR

      I think we all-

    21. JK

      You know, we're real people.

    22. JR

      Yeah.

    23. JK

      We know that. We gotta-

    24. CK

      We all agree on this.

    25. JK

      Yeah.

    26. JR

      What I, what I do want to say-

    27. JK

      But, but it's still rare, Joe. I mean, this is, to have, you know, this is pretty rare segment. I don't know that 2% of the people in America will have a patient leave the office and actually ask what they ate today, you know?

    28. JR

      Mm-hmm.

    29. CK

      Yeah.

    30. JK

      I mean, it's-

  3. 8:40 – 11:51

    What epidemiology is—and why it’s controversial in nutrition

    1. JR

      Yeah, and if you can, just to illuminate this for people, what is the problem with e- epidemiology studies?

    2. JK

      (sighs)

    3. CK

      Oh boy.

    4. JK

      Sure. You know, I'll, I'll, I'll go there real quick.

    5. JR

      Okay.

    6. JK

      I mean, I don't think there's a problem, but they're a part of the solution. They're not the whole solution. A lot of scientists... I'll give a shout-out to Los Angeles's brightest nutrition mind and somebody that I know Chris honors too, Valter Longo. No label, not vegan, not paleo, not nothing. He's at USC, been honored by the Royal Academy of Swedish Medicine, which is a Nobel Prize committee and this and that. Um, he says, you know, you do basic science and then you do an epidemiology study to test the hypothesis. You see something in a petri dish, you see something in a mouse, you see something in a cell, you ask the question, is animal protein pro-longevity, pro-early aging because of pathways-

    7. JR

      Do you mind explaining epidemiology studies to people?

    8. JK

      Sure. So you would take that concept, I'll just run with that, that, you know, you, um, you look at, uh, uh, an amino acid found in animal protein, throw out methionine and leucine. In a petri dish, looks like it might cause accelerated aging in a single cell. That's biochemistry. That is something you honor, but it's a long jump from there to human. Then you look at a database. Sometimes it's a crappy old database. Sometimes it's Harvard has these gigantic ongoing database. Uh, Loma Linda, an hour from here, has a gigantic database. And there's others, e- EPIC study, this PURE study I mentioned. You can test a hypothesis of what happens if our data may be crappy, but it's still data, and it allows you to go further with 100,000 people, 50,000 people, 500,000 people. Can w-... Do we have the data to ask the question, does protein correlate with survival, protein correlate with early death, animal protein, plant protein? These studies have been coming out a lot lately, and they let you parse it out. Now, it's what, you know, Chris talks about. Do you know everything about the person in the database? Do you know smoke or do you know diabetes, do they go to the gym, do they lift weights, they smoke dope, do they smoke crack? You don't, you don't know everything. Nowadays, most of these things are gonna ask all your blood pressure, cholesterol, all the basics to try and take those factors away and isolate the question you're asking. It'll be imperfect. And then you go to the best study, but it won't, it won't happen often, the randomized clinical trial. I mean, there's never been a randomized clinical trial of smoking, 'cause that'd be unethical. You're never gonna do it. It was epidemiology that proved an association strong enough to r- recommend to the public, "Don't smoke." There'll never be a randomized trial. And not everything... Parachutes don't need a randomized trial. You know, um, you know, taking folic acid in a pregnant woman to not have spina bifida doesn't need a randomized trial. I mean, there's some things that are so pressing, the public health can't allow that. And there's even more than that. The last little section is, um, you can study old people. Chris enjoys studying ancient societies. I enjoy studying the elderly in current, you know, modern, uh, environment, which is called the Blue Zones, and there's others. But, you know, what do old people do? The old, healthy people, what we would like to be. Would you like to be 90 and have your brains and have your joints and everything working? Well, we have that database. So the- that little four, uh, pod, uh, pedestal to sit on, basic epidemiology randomized studies and centenarian studies allows you to make reasonable conclusions. You know, we'll be wrong sometimes.

    9. JR

      Mm-hmm.

    10. JK

      We're not gonna be very wrong.

    11. JR

      Chris?

  4. 11:51 – 30:02

    Kresser’s three big epidemiology problems: bad dietary recall, healthy-user bias, and tiny risk signals

    1. CK

      I, I think there's huge problems with epidemiology. So obser-... E- epidemiology observational studies are studies that look at a certain group of people and then try to draw inferences from their behavior about associations with disease. So let's say we, we take a group and we look and see, you know, how much saturated fat are they eating, and we separate them into, you know, low consumption, medium consumption, high consumption. And in a prospective study where we're watching them over time, we might then look 20 years later and see how many people had heart attacks and died. Okay, and then we try to, you know, correlate that with their amount of saturated fat intake. Now, uh, I actually j- uh, just published two articles with, um-... going in detail, uh, on the problems with observational nutritional research and, um, you can find them at Cresser.co/Rogan. There's a whole bunch of information that we're gonna be talking about today there, so people can go and get the details themselves. But I'll just give you three of the, I think the mo- the worst problems with nutritional epidemiology. The first is data collection. So there's a saying in science, which is that, um, data are, are only as good as the to- as the tool used to collect them. All right? And in nutritional observational studies, the tool used to collect data is a questionnaire. Okay? (laughs) And so that relies completely on memory, and we know that memory is not a precise, accurate, or literal representation of events. It's more like a highly edited anecdote of what happened in the past. And back-

    2. JK

      It's a little bit like the Kavanaugh thing going on right now. (laughs)

    3. CK

      Yeah. (laughs) Back in the, back in the 13th century you had Francis Bacon who said, "For something to be scientific, it has to be independently observable, measurable, and falsifiable, and then accurate and vali-valid." And so let's use an analogy. If you're sitting there eating an apple, and I'm watching you do that, I can observe that you're eating the apple. I can measure how much of the apple you eat, and I can confirm or refute that you're eating the apple. If you tell me that you were eating an apple 15 years ago or 10 years ago, I obviously can't observe that. I obviously can't measure it, and I obviously can't confirm or refute it. And yet our entire foundation of nutritional epidemiology is based on that, basically people reporting on what they ate at some time in the past. So, you know, how much of a problem is this? Uh, there's a guy named Edward Archer who's done some really interesting, uh, studies, and he looked at the NHANES data, the Nurses' Health data, which is one of the longest running nutrition studies, 39 years, and he found that the, the self-reported calorie intake in those studies was either physiologically implausible or incompatible with life.

    4. JK

      (laughs)

    5. CK

      So the average person in those studies reported a calorie intake that would not support an elderly, bedridden, frail woman.

    6. JR

      (laughs) So they just-

    7. CK

      So-

    8. JR

      ... it's just inaccurate.

    9. CK

      It's completely inaccurate. And the, the people who are most likely to under-report are people who are overweight and obese. So if you... If calories are that much under-reported, all nutrition comes through calories. Everything we get, fat, protein, carbohydrates, micronutrients, they all come through calories. So if, if calories are that under-reported, that completely invalidates the data set.

    10. JR

      So this is an obesity study, so they're, they're under-reported because of shame?

    11. CK

      It's not an obesity study.

    12. JR

      Oh.

    13. CK

      It's just every... Americans are overweight and obese.

    14. JR

      Right. Yeah.

    15. CK

      The majority of Americans are overweight and obese, so in any data set of Americans, you're gonna have the majority of them overweight or over obese, so, or, or, or obese. So that's the first problem. The second problem is a healthy user bias, which I know we talked about before. But it's basically the idea that because, you know, when someone engages in an unhealthy and a behavior that's perceived as unhealthy, they are more likely to engage in other behaviors that are perceived as unhealthy and vice versa. So let's say you do a study of people who ate, eat more red meat. Well, red meat has been perceived as unhealthy for a long time. And so what we know is that in those observational studies, the people who eat more red meat are also smoking more, they have higher body mass index, they're eating less, fewer fruits and vegetables, they have a lower level of education, they're less physically active. So how do you know that it's the red meat that's causing the problem and not those other things? You don't, because they cannot control for all of those potential confounding factors. The third problem with observational research, and maybe the biggest, is that the, the, the relative risks in nutrition are so low that they're indistinguishable from chance. So in fields outside of nutrition and epidemiology, nobody would consider a relative risk, an increase in risk less than 100%, a doubling, to be really worth paying attention to. So to put this in perspective, the observational studies that Joel was referring to that confirm that y- s- that cigarette smoking led to lung cancer, that showed an, uh, a one- between a 1000% and 3000% increase in s- uh, lung cancer in smokers. Okay? And the studies that have shown that eating aflatoxin, which is a mycotoxin, increase liver cancer risk, that's 600% increase. Okay? The IAR- the IARC, the WHO report that suggested that processed red meat was a carcinogen, that was 18% increase. Most epidemiologists-

    16. JK

      Hmm.

    17. CK

      ... you talk to will say, "That is so low that it's really indisting- uh, indistinguishable from chance, especially given the healthy user bias and the problems with the data collection that I mentioned before."

    18. JR

      So the studies that are cited, so when people are talking about red meat causes cancer, they're literally talking about something that showed an 18% increase.

    19. CK

      Yeah. Right.

    20. JR

      And-

    21. CK

      Yeah.

    22. JR

      ... this is over-

    23. CK

      Which-

    24. JR

      ... people that are also-

    25. CK

      That-

    26. JR

      ... consuming sugar, other-

    27. CK

      So that, so that, that translates into four and a half, there were four and a half cases of cancer out of 100 in people with no, lowest intake of processed meat, and that went up to 5.3 cases out of 100 in people with the highest intake of processed meat. So, you know, there are quotes like y- if you, if you look even 20 years ago, like, there's an article in Science, um, the journal Science, and Marcia Angell, who was the former editor of New England Journal of Medicine, was quoted as saying, "We wouldn't even accept a paper for publication if it didn't have at least a 200% increase, especially if it was a new association or the, the, the biological mechanism wasn't known." And here we are today.

    28. JK

      ... saying that, you know, this increase that by 7% or by 10%, and when you consider that the data is usually questionnaires of what people ate, and all of these confounding factors like exercise and, and fruit and vegetable consumption and things like that are not accounted for, then we're really just playing games with numbers. Is part of the problem as well that there's this clickbait culture now in terms of journalism- Well, sure. ... where they just want to publish something that says- Of course. ... a study shows, you know, 18% of people eat red meat get cancer?

    29. CK

      Yeah.

    30. JK

      That's a huge problem, and there is a study that was done that showed that 43% of findings that came from observational studies were portrayed in the media as being causal. Mm. Which, which any epidemiologist would tell you that that's-

  5. 30:02 – 37:36

    Processed meat and cancer: WHO/IARC claims vs. context and absolute risk

    1. JK

      Quick, quick little thing. I just wanna go back for a minute to meat and cancer. World Health Organization is not a vegan group, it's not a nothing group. You know, it's a fairly well-respected international organization that puts out health, uh, claims. So although I ... absolutely, Chris had the data right. 18% increase in cancer risk with processed red meat. I wanna make that clear. I hope you don't eat too many hot dogs, salami, baloney, pepperoni. That's the, uh-

    2. JR

      Nitrates.

    3. JK

      Yeah. Uh, well, it may be more than nitrates, but it's just a whole-

    4. JR

      Preservatives.

    5. JK

      ... it's the salt, it's the preservatives, it's junky pieces of the animal that they're putting into a hot dog. That was a group. That's an 18% increase. You can go 4.5% to 5.5%. That's still 50 to 60,000 people a year that get colon cancer if that data's right. They wouldn't get colon cancer if they just would stop eating hot dogs. At a minimum, and I know Chris will agree, frigging hospitals are serving hot dogs and the data's out there that it promotes cancer to people getting chemotherapy with the IV pole. It's insanity. So, 50,000 people avoid colorectal cancer with small differences that the World Health Organization suggests. It was 800 papers and 22 world experts. There's no perfect study, but when they announced that October 25th, 2015, the world was shocked. You just said that processed red meat causes cancer. They didn't say related. They were strong enough data to say cause. They've been beat up. They published more data. They haven't backed down. I just wanna put that out. The healthy user bias will exist in the paleo community when the study's done 'cause they ... I mean, look at Paleo FX. They're ... it's everything, and I honor that. I mean, we should promote healthy lifestyle. Food's only one part of this. I mean, we will all at this table live longer than the average American. We're not smoking two pack a day. We don't have 38-inch waistlines, the whole deal. We're doing the whole thing. Hopefully you guys are enjoying a little cabernet now and then, or ... uh, that's always on the list. Just don't overdo it. But the healthy user bias, that particular ... that health food study paper, it's 1996, it's a pretty old paper. In the paper in the limitations, they beat themselves up. "We were missing this or that." Anybody just read the paper. It's not that it doesn't bring up an interesting point, but to say that we, again, throw away all these papers 'cause they are biased. Lastly, and I'm done. Multivariate analysis. Chris was just talking about better studies that factor all this stuff. Let's not bore your audience with statistics, statistics. But there's certainly the ability now to say, does animal protein associate with an increased risk of cancer? And put in smoking and weight and diabetes and blood pressure and vegetable intake and alcohol intake and family history, and then you just isolate the one thing.... is there foibles, are there downsides? Of course. But all modern epidemiology does multivariate analysis to try and isolate it. You know, you can cast stones everywhere, but, you know, there are, you know, the World Health Organization, I mean, there's 21 organizations say, "Limit your saturated fat in your diet," and none that are international societies say, "Increase it." So you put, uh ... Nutrition science needs to incorporate as much as you can with as much reliability, and at the end of the day, you can see we'll still have questions.

    6. CK

      Well-

    7. JK

      But I can't throw-

    8. CK

      ... the organi- the US used to say, "Don't eat much cholesterol." Now they don't. They used to say, "Limit your total fat," and now they don't.

    9. JK

      That's wrong.

    10. CK

      Because they've gone out ... It's not wrong, actually.

    11. JR

      Well, it is wrong.

    12. JK

      Well, the USDA says in the guideline-

    13. CK

      But, b- but-

    14. JK

      ... "Eat as little cholesterol as possible."

    15. CK

      ... it says, "Cholesterol is not a nutrient of concern" in that sentence.

    16. JK

      Because they couldn't identify the exact milligram to recommend. It used to be 300. They said-

    17. CK

      Because the science doesn't support-

    18. JK

      No, it's 'cause inter-

    19. CK

      ... limiting dietary cholesterol anymore. Let me go back and, and to the ... this question of-

    20. JK

      That's wrong. They say, "Limit cholesterol."

    21. CK

      Hold on. You-

    22. JK

      They say, "Limit cholesterol to as little as possible." I mean-

    23. JR

      But who, what, what's this th- they? Who is they and-

    24. JK

      USDA. USDA.

    25. JR

      ... the USDA?

    26. JK

      The guidelines come out every five years, and they are im- uh, used for school menus and hospital menus. It was a big buzz in 2016 when it was announced. They no longer were giving a so many milligrams of cholesterol a day you'd never exceed.

    27. JR

      Okay.

    28. JK

      They said, "We can't pick the number."

    29. JR

      But isn't USDA behind the curve in, in terms of science?

    30. CK

      Yeah, so, so let's, let's, but they're influ- they're influential.

  6. 37:36 – 39:25

    Practical ‘harm reduction’ tips: veggies with meat, marinades, and cooking chemistry

    1. JK

      Okay. I think we have a gong moment, 'cause I'm, I really want you listeners to come away with a few tips from Chris and I that make a difference. 'Cause I know your listeners aren't gonna stop eating meat at the end of this show.

    2. JR

      They might.

    3. JK

      Chris just said-Meat with vegetables is safer than meat without vegetables. Meat with chlorophyll is safer than meat without. I can give you cardiac studies that agree. I t- I teach-

    4. JR

      Well, he-

    5. JK

      I teach-

    6. JR

      ... he said processed meat.

    7. JK

      Well, it's all meat. I teach that if you-

    8. JR

      Oh, is it all meat?

    9. JK

      Yeah. If you-

    10. JR

      Is it the same?

    11. JK

      No. Listen, we agree here. I want people to hear this.

    12. JR

      But do we?

    13. JK

      When- when you grill-

    14. JR

      Oh, whatever. Yes. (laughs)

    15. JK

      How many people in the audience grill, barbecue? Everybody. If you grill meat, another chemical group that's formed are called advanced glycation end products, AGEs, that go along with the list. But if you grill meat that's marinated, and we want ... This is the tip, in dark beer. This is science, randomized science. You put a piece of beef in dark beer and you grill it, you don't create as many of these toxic chemicals as a dried piece of beef. So let's, uh, let's, like, right now, everybody listening, next time you eat meat, get a salad. Next time you eat meat, order broccoli. Next time you have bacon, get a, get a, you know, sliced tomatoes. You will actually improve your health. There's this classic, and now I'm shifting to cardiology, that they took, uh, healthy volunteers and they took them down to the hospital cafeteria and they fed them a hospital burger, and they were measuring on their arm how their ar- arteries function. Cardiology topic. Artery function goes down in three hours when you eat a hospital burger. It acts like you just had a toxin in your body. You did. They took the same group a week later. They had them eat the same burger with a big salad. They didn't see that finding. I mean, I want this to be an important point. You know, everybody should be jamming fruits and vegetables, or at least vegetables with some fruits. You can go low-glycemic berries. I'm fine with papayas, cantaloupe, and apples. But, you know, up your veggies, listeners, and you'll counteract a lot of the crap that's out there in the world. I- it's an important message.

    16. JR

      I don't disagree with that.

    17. JK

      No, you know you wouldn't. You have to.

  7. 39:25 – 44:52

    The saturated fat showdown begins: why guidelines still say ‘limit it’

    1. JR

      We glossed over this very quickly in the beginning of this, but there was a dispute about cholesterol and a dispute about saturated fat. Um-

    2. JK

      Nah. Serious?

    3. JR

      You were saying that saturated fat ... that there's recommendations to reduce saturated fat.

    4. JK

      Yeah, there's-

    5. JR

      And reduce cholesterol.

    6. JK

      So let- let me go ... Real quick overview, and I'm gonna talk fast. So just-

    7. JR

      Just talk normal.

    8. JK

      It was felt.

    9. JR

      You, we got plenty of time. (laughs)

    10. JK

      It was felt. So until the '40s, it was not common to have a heart attack. Heart attacks were described in 1916. Not to say they didn't happen, but the first medical article that used the word myocardium infarction, 1916. 1940, there were not many heart attacks seen in a modern American city. After World War II, we ... our economy went up. In the city of minne- Minneapolis, executives started suffering heart attacks. It was also Franklin Delano Roosevelt died of high blood pressure a few years later. Eisenhower had a massive heart attack. That's when our government, National Institutes of Health, started funneling major money into studies like the Framingham Study. You're from Newton.

    11. JR

      Mm-hmm.

    12. JK

      Framingham's a city outside of Boston, and they basically invaded this town in 1958 till today, said, "We're spending money. We're gonna figure this crap out." The idea had come up, heart disease wasn't just aging. Heart disease could be explained by what's called risk factors. Smoking might not. You can smoke and live to 100, but it's gonna increase your risk. And then they got into blood pressure and cholesterol and, uh, uh, family history. They identified what we call risk factors. So until that point, diet was not considered a factor in the development, the number one killer of men and women. I wanna point out, and Chris puts this on his website. I do too. During this interview, every 39 seconds, an American dies of heart disease. Every 39 seconds, most frequent cause of death. So there will be about 200 people, perhaps, that will die during this podcast of the number one killer. And 80% of it's preventable. Chris is gonna prevent some. I'm gonna prevent some, 'cause the biggest enemy out there is smoking and crap diet, calorie-rich and processed foods, crap SAD diet, standard American diet. It became apparent in the early 1950s, diet might play a role. And a notorious scientist and many others, his name, Dr. Ancel Keys, PhD, PhD, had two of them, suggested dietary fat might be a factor. It was a hypothesis. It's this early stage. Epidemiology doesn't prove anything. He went out and did studies. Other people went out and did studies. And the idea transitioned. Actually, he was criticized for saying dietary fat. The dis- ... The, uh, the conversation transitioned. There's some good fats, like, uh, omega-3 fatty acids are essential. You have to have them. And then maybe polyunsaturated fats from plants are more healthful. But the focus went on saturated fat in food, which is basically chicken, red meat, pizza. Those are the highest sources. And, um, subsequently, enough data accumulated that guidelines started to suggest, we've got this huge problem with heart disease. We should limit saturated fat in the diet. It was never limit all fat. Eh, 35% of calories. That's not in anybody's, word, a, uh, low fat diet. Um, and that has now promulgated in 21 international statements. There is no opposite. Whether it's the World Health Organization, American Heart Association, American College of Cardiology, whether it's the institute of ... Institute of Medicine says, "Eat as little saturated fat as possible." They couldn't be more clear. And these are highbrow. These are not, uh, associated with vegan movements or paleo movements or whatever. These are medical authorities. If there was half and half, you'd say controversy. 21 of 21 say the same thing. They might pick a different cutoff point, but we will enhance the health and cut down the number one killer. Whether it's in Asia, whether it's Europe, whether it's Australia, whether it's, uh, in the United States, there's unanimity that-

    13. JR

      Okay, but why did they- So- ... come to the conclusion it's saturated fat?

    14. JK

      Well-

    15. JR

      So-

    16. JK

      We- well, the basic science, 'cause there is basic science, and let me tell you, when you eat foods rich in saturated fat, which is called meat, cheese, eggs, and such, receptors on your liver for cholesterol ... I've got cholesterol in my blood. I'd like to get some of it out into the liver to be metabolized. I need a receptor. You eat saturated fats, receptors go down. Cholesterol has no place to go. Cholesterol stays in the blood, bumps into your artery wall. I'm putting a stent in your artery. That's the basic biochemistry. Then they had epidemiology studies. Flawed, perfect, it doesn't matter. There was so-

    17. JR

      It does matter.

    18. JK

      Whoa, whoa, whoa. Whoa, Chris, Chris, thank you very much.

    19. JR

      (laughs)

    20. JK

      Then they did controlled trials. Three ... I- uh, everybody just go read Clark 1997, 395 ... It's called Metabolic Studies. Change the diet, see what happens. You add saturated fat, cholesterol skyrockets on average, not in a single person. If I gave you a steak, Chris a steak, and me a steak, our cholesterol would rise differently. It would rise. It would rise differently. It's our microbiome. It's our genetics. It would rise. So i- i- that's a problem in the studies when you average everything together. So they had that and then finally, finally, they looked at populations that live over 100. These are called the pillars of longevity. They don't eat foods rich in saturated fat. They have a little, they don't have a lot. They eat a lot of olive oil in Italy and Greece. They eat almost no dietary fat in Okinawa, Japan, and they live, they have the greatest longevity in the world in 1970. They eat almost no dietary fat, about 6, 7%.

    21. JR

      All right, let's, let's- Okay. We're getting-

    22. JK

      So you put all that together-

    23. JR

      We're getting into the weeds here.

    24. JK

      Well, no. It's actually ... That is the basis for a major push to say cut back on animal products, 'cause that's largely, with exception of coconut and, um, palm, uh, you know, where saturated fat comes from. So the-... to, to negate that is to throw out every major health agency in the world. And I don't believe Chris Kresser can do that. No disrespect, I don't think Chris can throw out 100 years of cholesterol research. Let's- let's back up a little bit here.

  8. 44:52 – 1:45:20

    Meta-analyses vs. mechanistic biology: what counts as ‘best evidence’

    1. CK

      Okay, let's back up. Yeah. So, um, first of all, every food that we consume has all of the fats in it: polyunsaturated, monounsaturated, and saturated fat. And in fact, two tablespoons of olive oil has more saturated fat than a seven-ounce pork chop. That's a little-known fact. Um, the, the oily fish, mackerel, you know, which all of these health agencies that Joel is talking about advises us to eat, has twice the total fat and one-and-a-half times the saturated fat that we're, of the meat that we're told to avoid. Um, does it make sense that nature, you know, would include, th- that you could eat, uh, uh, you know, mackerel and the polyunsaturated fats in it are good for you, but the saturated fat in it is bad for you? That's kind of nonsensical. But, you know, t- let's talk a little bit more about the research. So, um, there never really was good evidence to suggest that dietary cholesterol and saturated fat are connected to heart disease. And, uh, Zoe Harcombe, who's a, has a PhD, a nutritional researcher, she wrote her thesis, her PhD thesis, on the evidence back in the '70s that led to the restrictions on, uh, saturated fat and cholesterol. And then she also reviewed the evidence year, y- uh, all the way up until 2016. And, and if, uh, I have th- um, this information on my website, if you go kresser.co/rogan, you can find it. And what you'll find is, there never was en- really good, uh, evidence to support the limitations on di- on saturated fat and cholesterol. And people have started to look at this more recently and, uh, for example, you have a meta-analysis of observational studies, including about 350,000 participants recently that found no relationship between saturated fat intake and cardiovascular disease. You have an exhaustive review of studies, something like 25 randomized controlled trials, gold standard of clinical evidence, and s- almost 40 observational studies involving 650,000 participants. And I'll read you a quote from the conclusion. "Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of saturated fatty acids." Now, look, one of my favorite quotes is the ph- the philosopher Anatole France: "Even if 50 million people say a foolish thing, it's still a foolish thing." And the other thing to consider is that the history of science is really the history of most scientists being wrong about most things most of the time. And, uh, you know, sci- i- in science, we have to continually challenge our, our hypotheses and try to falsify them, and that's how the scientific process moves forward. And that's why in 2010, the US, uh, federal government removed restrictions on total fat, whereas before there was a restriction on total fat, because they, they acknowledged that the research was showing that not all fat is the same and that, y- you know, we don't need to be restricting fat from avocados and things like that. And then in 2015, they removed the restriction on dietary cholesterol. Now, they did that fairly quietly, because how do you think it looks when people have been told to, you know, limit their fat and limit their cholesterol, and then the, the federal agency goes back on that lim- th- that recommendation after so many years of telling people to do that? People lose faith in the agencies that are, that are issuing these guidelines, you k- I ... And don't take it from me. You know, I'm, I'm, I'm not expecting anyone to believe me, and that's why I've put all of the, the studies and the research supporting this at kresser.co/rogan. But how about John Ioannidis, who's one of the most renowned epidemiologists in the world? He's a professor of medicine at Stanford, and he has wrote some, written some scathing critiques of nutritional research recently that have been published in JAMA and British Medical Journal. So here's a quote from one of them: "Some nutrition scientists and much of the public often consider epidemiological associations of nutritional factors to represent causal effects that can inform public health policy and guidelines. However, the emerging picture of nutritional epidemiology is difficult to reconcile with good scientific principles. The field needs radical reform." (laughs) And he goes on to point out that meta-analyses of observational studies have found that almost all foods are associated with a higher risk of death if you crunch the data in certain ways. So, uh, it's not enough to say that d- you know, governments are recommending this or that. We have to look at the science and what the science is saying. And as I said, you, two recent meta-analyses covering over a million people are not showing a relationship between saturated fat and heart disease, and they're not showing any benefit from replacing saturated fat with polyunsaturated fats.

    2. JR

      So these organizations, Joel, that-

    3. CK

      Yeah.

    4. JR

      ... you were describing, why do you think that they recommend ... Based on what Chris has just said, why do you think that they recommend reducing your saturated fat, reducing your cholesterol?

    5. JK

      Okay. Um, and thank you. And, you know, the, the importance here, we're s- we are, you know, technical in the weeds, but I wanna bring it back. This discussion is, do you have a stroke, heart attack, erectile dysfunction, lose a leg, or do you not, because at least one factor in development of these horrible medical problems that are 80% preventable, at least one of it is your nutrition and the content of your nutrition? I mean, there's no doubt. It's the single most important factor. It's never been the only factor.

    6. JR

      Okay, but why do you think these organizations-

    7. JK

      So the stuff matters. Right.

    8. JR

      ... are saying this if he's saying-

    9. JK

      Okay. So-

    10. JR

      ... that the studies don't support that?

    11. JK

      Well, uh, I disagree that the science ... And I wanna be s- very specific. Let's talk about cholesterol and let's talk about saturated fat.

    12. JR

      Okay.

    13. JK

      So stay with saturated fat, 'cause there is differences there. They're-

    14. JR

      Okay.

    15. JK

      ... both, uh, you know, c- contents of food, fatty contents of food, but they're chemically different and the volume weight is very, very different. Um, cholesterol only comes from animals. Saturated fat is in animals and plants, uh, depending on the food source. So when this rise in heart attacks developed, research began, 1948, 1950, 1958. There were observations made that carefully done dietary logs suggested, these were hypotheses, there might be a connection between what you eat and heart attacks, and then it's centered on, um, you know, is it foods high in protein, foods high in sugar, foods high in fatty sources? Ultimately, they got sophisticated. Foods high in-... plant fat sources, foods high in animal fat sources. So by the late 1950s, there was a very strong consensus already that foods high in animal products with saturated fat, they go together, we're talking meat, egg, and cheese, may be a role. Why? L- let me give you a great example. In 1959, you grew up in Japan, you have a cholesterol of 120, you almost never see a heart attack. You move to Hawaii because there's migration. Your cholesterol rises to 180. Welcome to America. Your heart attack risk triples. You move to this great city, Los Angeles, this was published in 1959, your cholesterol's now 210. You have 10 times the heart attack risk that you had when you lived in Japan. Genetics don't change that quick. This was within one generation. They're called Nisei, people that leave Japan to move to California, the Nisei, and there's the Nisei-Han study that tracked these people. Now, is it the air? Is it that they adopted other bad habits? Sure, it could be, but within a very short time, they had 10 times the risk of heart attack. So public research and dollars, this stuff matters.

    16. JR

      But why is this correlated with animal fats and proteins-

    17. JK

      'Cause they're, yeah.

    18. JR

      ... and why isn't it correlated with sugar-

    19. JK

      Right.

    20. JR

      ... and refined carbohydrates?

    21. JK

      So, carefully done studies say, and I think we all agree, more so now 'cause we're overweight and now we're more insulin resistant and added sugars in the diet are more important in 2018 than they were when the country was thin in 1960. They weren't good then, they aren't good now. But when you parse it out, multivariate analysis, there's a stronger relationship between the number one food in studies like this is usually butter, more than red meat, it's actually butter. That's just an R value. It's called statistic. I don't wanna go so deep into statistics. It is. Somewhere there is sugar. I'll give you a classic study. If you could hold sugar the same and increase dietary saturated fat, heart disease rockets. If you could hold saturated fat the same and increase sugar in these manipulations, coronary heart disease doesn't increase. Let's point something out. I've been inside of hearts 15,000 times, I've never scooped sugar out of a blocked artery. I scooped cholesterol out of blocked arteries. 20% of every blockage in a heart is cholesterol. It's a fact that was discovered in 1910. It's never varied. Then we fed animal, uh-

    22. JR

      Let's pause for a second.

    23. JK

      Yeah.

    24. JR

      Chris, do you have something to say about that?

    25. CK

      Yeah. So that doesn't mean that the cholesterol is there because people were eating it, Joel. You know that.

    26. JK

      It could be though.

    27. JR

      But hold on.

    28. CK

      And, and let me... Let's say, let's look at the, what the research says again here. So they've done controlled feeding studies where they fed people two to four eggs a day, and those show that in 75% of cases has zero impact on blood cholesterol levels. For the other 25% of people, they're termed hyper-responders. And in that group, dietary cholesterol r- r- does modestly increase LDL cholesterol, but it also increases HDL cholesterol and it does not increase the risk of heart disease. This is why the, the guidelines were changed on dietary cholesterol, is there is no evidence that, that consuming dietary cholesterol increases the risk of blood cholesterol in most people. And even when it does, there's no evidence that it increases the risk of a heart attack, which is again, why the dietary guidelines changed. For saturated fat, again, it... Most of the studies that showed harm were short-term studies. These, uh, longer term studies have shown that on average, eating saturated fat does not increase the saturated fat levels in the blood. And of all of the long-term studies that looked at this, only one showed any association between saturated fat intake and, uh, cholesterol levels in the blood. Then we have a meta-analysis, lots of meta-analyses actually, but one of the, uh, best known meta-analyses was of 17 randomized controlled trials of low-carb diets that were high in saturated fats in... Published in the journal Obesity Reviews, and they found that low-carb diets neither increased nor decreased LDL cholesterol, but what they did find was that low-carb diets were associated with decrease in body weight, improvements in several cardiovascular risks, risk factors, including triglycerides, fasting glucose, blood pressure, body mass index, abdominal circumference, plasma insulin, C-reactive protein, as well as an increase in HDL cholesterol. Now, there have now been 10 meta-analyses of randomized controlled trials looking at low-carb diets for weight loss. All 10 showed that, uh, the low-carb diet either outperformed in most cases or was, was on the s- at the same level as low-fat diets. There have been several meta-analyses now, you can see them all at kresser.co/rogen, that have looked at, um, low-carb diets for diabetes and even cardiovascular risk markers, and all of these meta-analyses have found that low-carb diets are superior for glycemic control, for reducing insulin, for reducing triglycerides, and have beneficial effects across the board without increasing cardiovascular risk markers. So we're now... We're t- we're talking about (laughs) randomized controlled trials, which is the best form of evidence that we have, and we're not seeing any harm from incr- you know, increased consumption of saturated fat. So-

    29. JR

      So is the problem that you're citing epidemiology studies from the 1940s and the 1950s?

    30. JK

      Well...

Episode duration: 3:47:38

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