"Forks Over Knives": Is a Vegetarian Diet Better For You?

A viral documentary says a "whole foods plant-based diet" will prevent heart disease and cure cancer. But once we look into the MEAT of the matter will we find factual CREAM of the crop or will we  cry FOWL? (we're so sorry)

Thanks to Katherine Flegal for helping Mike with this episode!

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Links!

• Health effects associated with consumption of unprocessed red meat: a Burden of Proof study
• Unprocessed Red Meat and Processed Meat Consumption: Dietary Guideline Recommendations From the Nutritional Recommendations (NutriRECS) Consortium
• Present status of the aflatoxin situation in the Philippines
• The role of natural consequences in the changing death patterns
• Dietary Protein and Amino Acids in Vegetarian Diets—A Review
• Quality of Plant-Based Diet and Risk of Total, Ischemic, and Hemorrhagic Stroke
• Parachute use to prevent death and major trauma when jumping from aircraft: randomized controlled trial
• Do We Really Know What Makes Us Healthy?
• Observational evidence does not necessarily imply causation
• The Problem with Observational Studies (Epidemiology)
• Vegetarian Diet Patterns and Chronic Disease Risk: What We Know and What We Don’t
• The rise, the fall and the renaissance of vitamin E

Thanks to Doctor Dreamchip for our lovely theme song!

Transcript

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[Maintenance Phase theme music]

Michael: Tag us in what is your meat based--

Aubrey: Meat based?

Michael: Protein, high protein tagline. 

Aubrey: You're already hinting at what my tagline was going to be. 

Hi, everybody, and welcome to Maintenance Phase, the podcast that just wants to know where you're getting your protein. Where are you getting your protein? Aminos. Are you set for aminos? Are you getting enough aminos? 

Michael: You are a woman who lives in Portland and has a lot of vegans and vegetarians in your life.

Aubrey: Correct.

Michael: I'm Michael Hobbes.

Aubrey: I'm Aubrey Gordon. If you would like to support the show, you can do that at patreon.com/maintenancephase. [Michael echoes Aubrey] You can buy T-shirts, mugs, tote bags, all manner of things at TeePublic. [Michael echoes Aubrey again] And you can subscribe through Apple Podcasts. [Michael echoes Aubrey again] It's the same audio content as Patreon content. [And Michael echoes Aubrey again] My quiet little repeating machine.

Michael: I know I keep trying to throw you off, and it never works.

Aubrey: Today we're getting in a little time machine, and we're going back to 2011, apparently. 

Michael: This is a listener request. Since we did our Super Size Me episode, this is by far the most requested movie debunking for us to do. Today, we are talking about Forks Over Knives, which came out in 2011. I think it was one of the first streaming documentaries. I think it was like when everybody was getting Netflix. A huge number of people watched this movie. The book based on the movie was the number one New York Times bestseller. 

Aubrey: Yeah. This comes from an era where there was a lot of media about cord cutters. You wouldn't have cable anymore? Imagine. 

Michael: What do about Forks Over Knives, Aubrey? 

Aubrey: What I remember its hypothesis as being is that a vegan diet was healthier and that it would lead to a longer life and that it would prevent chronic diseases. It was about sort of the origins of disease being with eating meat and dairy.

Michael: Yes.

Aubrey: Am I getting that right? Am I in the right neighborhood? 

Michael: If anything, you're underselling it. This movie explicitly says that a vegan diet will prevent and reverse all forms of chronic disease. 

Aubrey: Okay, good. 

Michael: Heart disease, diabetes. At one point, they mentioned dandruff. 

Aubrey: Halitosis, flatulence.

Michael: That's one thing I know that it won't solve. But then okay, because this is a left-wing podcast, I feel like we have to start with a series of tedious disclaimers and meta conversation about what we're going to do in this episode. 

Aubrey: Let’s do it. Let's roll. 

Michael: I really did go into this fresh. I have never seen this movie. I have never been a sort of pro vegetarian person, but I've also never been like, anti-vegetarian person. I have a lot of vegetarians and vegans in my life. I've always felt a spiritual kinship with vegetarians and vegans because the stereotype of them is that they're constantly lecturing you and they're announcing like, “I'm a vegan and you're not.” I am sure those people exist. I have never come across anyone like that.

Aubrey: Yeah, I have known one preachy vegan and it was just a preachy guy, who is vegan.

Michael: Yeah, some people tediously promote their own lifestyle and some of those people are vegans and some of those people are not. It's not clear to me that's a more common trait among vegans than among non-vegans.

Aubrey: I will say this, I have experienced infinitely more proselytizing from keto and intermittent fasting people.

Michael: Although you're not a representative sample because you do have a podcast where you do say that those things are trash, but still yes.

Aubrey: No, totally agree. I'm not your starting point for these conversations. No, no, no.

Michael: It is worth noting that the animal rights and climate change arguments for vegetarianism are just fucking true. There's nothing to debunk. It's like, yeah, the way that America treats animals is atrocious, sure. I'm not a vegetarian, but it's totally indefensible the way that we treat animals. And also, the climate and water impacts of a meat-eating diet are worse than a vegetarian vegan diet. They just are.

Aubrey: This also seems like a good place for our standard issue sort of reminder. You should eat however you want to eat. We don't care. Do what's right for you. We're going to talk about a movie and how this movie sells this particular way of being and sort of way of eating. But we're not talking about the individuals who eat in that way, nor are we passing judgment on what anyone else chooses or chooses not to eat.

Michael: Yeah, it's a very weird movie because it is just straightforwardly a propaganda film, and most of the factual claims in the movie do not hold up to even the most cursory scrutiny. But it's propaganda in service of something that I think is good. I think vegetarian diets are fine, and if you want to be a vegetarian for literally any reason, then you should do that.

Aubrey: Yeah, that's right.

I actually really appreciated this movie because first of all, it does a lot of things that I think are illustrative of the nature of how propaganda works and how you can convince people of things without technically lying, but just through selective omission of important context. And also, I learned a lot watching this and debunking this. I went down some really interesting rabbit holes. So mostly, we're just going to go through the movie and I'm just going to tell you what I learned. 

Aubrey: It feels really interesting to me because it's rare that you and I both go into a topic pretty fresh, like aware of the cultural conversations around it. But neither one of us had seen this film. Neither one of us had done the deep dive into sort of health claims around veganism and vegetarianism. Like you, I am not a vegetarian, not a vegan, not plant based. I eat meat, but not very much.

Michael: Yeah, that's kind of where I am too.

Aubrey: Wherever this lands, cool.

Michael: So, let's kick ourselves off by watching the first couple minutes of this movie. The opening montage. 

Aubrey: I love this.

Video Clip: Clearly, the Western diet is taking a toll. This should serve as a wake-up call. We have a growing problem, and the ones who are growing are us.

Food. It's central to our lives and traditions. Every special occasion seems to involve food and feasting. But could some of these same foods, including several that we think are good for our health, also be causing many of our most serious health problems? Indeed, we're facing a massive health crisis. No less than 40% of Americans today are obese, and about half of us are taking some form of prescription drug.

This could be the first generation of children in the United States that lives less than its parents. 

We spend $2.2 trillion a year on healthcare, over five times more than the defense budget. Yet we're sicker than ever. But could there be a single solution to all of these problems? A solution so comprehensive, yet so straightforward that it's mind boggling that more of us haven't taken it seriously? 

Someone has to stand up and say that the answer isn't another pill. The answer is spinach.

A growing number of researchers claim that if we eliminate or greatly reduce refined, processed, and animal-based foods, we can prevent and in certain cases even reverse several of our worst diseases. They say all we need to do is adopt a whole foods, plant-based diet. It sounds almost too simple to be true.” 

Aubrey: This is like the "er" example. This is the template for, "Fat people are killing us all."

Michael: Right. You can't tell from the audio, but this includes a lot of footage of headless fat people walking around. 

Aubrey: I mean, it really did feel like, “Oh, here we are in 2011.” It just felt like the really kind of shouty coverage that we got about this stuff for a long time. Also, lot of Maintenance Phase cameos in there. We get Richard Carmona, the Attorney General who started the "terrorism is the threat from without," and "obesity is the threat from within, the greatest threat to our national security."

Micheal: We got Bill Maher.

Aubrey: Bill fucking Maher. 

Michael: An authority on diet and lifestyle. 

Aubrey: "The answer is spinach. Take the stairs."

Michael: We also got two of the zombie statistics that we debunked in that episode. 

Aubrey: "This is the first generation that won't live as long as its parents."

Michael: Playing the hits. And then we also got, at the end, sort of the thesis statement of the movie, which is basically, “What if a plant-based diet could solve and reverse all of these issues?” So, I am not reading between the lines or unfairly paraphrasing when I say this. This is the overt thesis of this documentary. 

Aubrey: The other thing that I was going to say about that intro, there is this assumption that if you are taking a drug, you should not be taking a drug.

Michael: Yeah, I really don't like this stuff.

Aubrey: There are absolutely people who are taking drugs that make their heart keep going and make their lungs take in air and really basic biological functions. I mean, listen, there are drugs I take absolutely every day that have absolutely helped me stay alive at different points in my life. I don't think that's a moral failing of mine that my brain chemistry looks different than other people's brain chemistry.

Michael: It's also in keeping with a weird tendency of this movie to guild the lily. Fruits and vegetables are really good for you. People should eat fruits and vegetables. That's totally fine. But you don't need to say that eating fruits and vegetables will reverse your multiple sclerosis.

We then get a little The History of Food section, where it's like the same kind of stock footage, and we learn about Betty Crocker and frozen foods and all this kind of stuff. This is familiar from every other food documentary that came out around the same time, where it's just the rise of processed foods, and people are eating outside the home, and people are joining the workforce, blah, blah, blah. And then, we get to this section where we learn about the links between animal proteins and cancer. I'm going to send this to you.

Aubrey: Send this to me.

Audio clip: In the mid-1960s, Dr. Campbell was in the Philippines trying to get more protein to millions of malnourished children. To keep costs down, he and his colleagues decided not to use animal-based protein. The program was beginning to show success. But then, Dr. Campbell stumbled onto a piece of information that was extremely important. It centered on the more affluent families in the Philippines who were eating relatively high amounts of animal-based foods.

But at the same time, they were the ones most likely to have the children who were susceptible to getting liver cancer.

This was very unusual, since liver cancers are mainly found in adults.

But just the mere fact that they occurred in children said there's something here. This is pretty significant.

Shortly afterward, Dr. Campbell came across a scientific paper published in a little known Indian medical journal. It detailed work that had been done on a population of experimental rats that were first exposed to a carcinogen called aflatoxin, then fed a diet of casein, the main protein found in milk.

When they were testing the effect of protein on the development of liver cancer, they used two different levels of protein. They used 20% of total calories, and then they used a much lower level, 5%. 20% turned on cancer. 5% turned it off.

Aubrey: They love getting the shot of that Arby's sign.

Michael: I know. [laughs]

Aubrey: I've been to that Arby's. I mean, I haven't been to it, but I've been by that Arby's.

Michael: Yeah. You can tell they're going back to the History of Food stuff. "Americans discovered Arby's."

Aubrey: Okay, so, I will say, on the face of this, I'm sure that you're going to be like, “This never happened, and this paper was never read,” or something like that. But what I will say is just on the face of it, I find it really fascinating that the presumption that because this particular health phenomenon existed within children of affluent people, that the first place that they went to was diet to explain it. It's really odd to just be like, “It has to be their diet, and it's got to be the meat.” Like, what?

Michael: One thing this documentary does, and a lot of documentaries do, is they bombard you with a lot of information very quickly, and at the end of it, you're left with this impression of like, “Okay, wealthy kids in the Philippines were getting liver cancer. We looked into it. Apparently, it was the animal proteins giving them cancer.”

Aubrey: Right. This is the same kind of science communications that's in the fucking Zoloft bubble commercials where they're like, “One side of your brain produces the happy chemicals, and then the other side with the brownie face can't accept them.” This is science communications that assumes you don't really need to know what's actually happening here.

Michael: Right. The best science communications invites you to consider the complexity of the world, and the worst invites you to ignore the complexity. So, the paper that he's talking about, it's a study on rats' susceptibility to this toxin, aflatoxin. It's a mold that grows on corn and peanuts. And so, this was a real problem in a lot of countries for a long time. In humid environments, this mold grows. When you harvest the crops, you also harvest the mold, and kids end up eating this toxin. And yes, kids get liver cancer. Kids get all kinds of really awful effects of this toxin from eating mostly peanuts, but also corn, especially in the developing world.

What they're doing is they're not looking at whether milk protein causes cancer in rats. They're exposing rats to this carcinogen, to huge doses of this carcinogen. Some of them are like little vegan rats. Some of them are not vegan rats. And you're like, “Oh, the non-vegan rats got tumors," which is true. But it's like this is a specific effect of the toxin they're being given. This isn't just like rats existing in the world, and the little vegan rats don't get cancer. 

Aubrey: It's not the same thing as a human child, and it's not the same thing as eating corn once a week. Even if you wanted to do this study in rats, the rat answer would be, “Hey, man, feed them some of that corn, every once in a while.”

Michael: So, okay, let’s do some of the clip up. Let's go to 16:37 together.

Aubrey: There we go, 37. Bing, bang, boom. 

Michael: So, this is the text that they show on screen when they're describing this study. So, toward the bottom, read the sentence that starts with in all.

Aubrey: "In all, 30 rats on the high-protein diet and 12 on the low-protein diet survived for more than a year."

Michael: Low protein here means vegan, basically. Or this is the analog that they're inviting us to consider. 

Aubrey: So, wait, what the fuck? More of the high-protein diet rats survived? 

Michael: So, the vegan rats were twice as likely to die. They had to stop the study because the little vegan rats kept dying.

Aubrey: So, it's not useful for understanding humans. And also, it says the opposite of what it was going to say.

Michael: Exactly.

Aubrey: I feel like this is my new way of documentaries, is just pause on every block of text and be like, “Hang the fuck on, we're reading this entire thing.” 

Michael: So, when they talk about this obscure study published in an Indian Journal, the study is part of a two-part study. One of the studies, which is what they're referring to here, is about the growth of tumors in the rats. The other study is about why the rats kept fucking dying, and the vegan rats were much more likely to die. I am not going to say that this invalidates vegan diets. That would also be just as superficial as saying this proves vegan diets. But okay, if it's turning off cancer but you're more likely to die, then the cancer thing is kind of irrelevant. Like, we only care about cancer to the extent that it's killing people.

Aubrey: I love that a documentary would have this level of a self-own in it that if you pause it, it undoes its own work, it undermines itself if you read all of the text on screen. 

Michael: Okay, so then we get to the other protagonist of this documentary. This documentary basically follows these two doctors. One is T. Colin Campbell, that was the guy who we just met in the Philippines. The other one is named Caldwell Esselstyn. He is telling us about his work as a surgeon and how that led him to do his own research.

Audio clip: So, Dr. Esselstyn started investigating the global statistics on breast cancer. One of the facts he discovered was that the incidence of breast cancer in Kenya was far lower than it was in the United States. In fact, in 1978, the chances of a woman getting breast cancer in Kenya were 82 times lower than in the US. Dr. Esselstyn was even more surprised by the numbers he discovered for some other types of cancer.

In the entire nation of Japan, in 1958, how many autopsy-proven deaths were there from cancer of the prostate? 18.

In the same year, the US population was only about twice the size of Japan's, yet the number of prostate cancer deaths exceeded 14,000. Dr. Esselstyn also discovered that in the early 1970s, the risk for heart disease in rural China was 12 times lower than it was in the US. And in the highlands of Papua New Guinea, heart disease was rarely encountered. Even more compelling to Esselstyn was some historical data that had long been overlooked.

In World War II, the Germans occupied Norway. Among the first things they did was confiscate all the livestock and farm animals to provide supplies for their own troops. So, the Norwegians were forced to eat mainly plant-based foods.

Now, we look at the deaths in Norway just antecedent to this period from heart attack and stroke. Look at right up here, right at the very top, 1939. Bingo. In come the Germans, immediately [crosstalk] in the 1940. Wow, '41, '42, '43, '44, '45. Have we ever seen a population have their cardiovascular disease plummet like this from statins? But look what immediately happened with a cessation of hostilities in 1945. Back comes the meat, back comes the dairy, back comes the strokes and heart attacks.

Aubrey: Unh-hunh. Holy shit.

Michael: Describe the visual feast that we just had in the last 30 seconds of that.

Aubrey: Holy shit, Michael. First, I will say, while were watching this clip, I was like, “Oh, we are in peak Michael Hobbes territory.” Why are people dying of this thing in this country but not in this country, is prime grade-- Oh, I'm using meat metaphors. 

Michael: Yes, spurious correlations are the fillet of this documentary.

Aubrey: Then, we get a graphic that is one of the wildest things I have ever fucking seen in my life.

Michael: You go to 20:50 and see the chart in all of its glory. I know.

Aubrey: This is like Monty Python. The title of the graph is Mortality from Circulatory Diseases, Norway, 1927 to 1948. And what it shows is more people dying of heart disease. That peaks at about 1940, and they have superimposed, a little teeny tiny Nazi flag.

Michael: And it pops in pop-up video. It's like bloop, Nazis.

Aubrey: It goes [makes a pop sound]. And then, mortality from circulatory diseases plummets. 

Michael: You got to hand it to them. 

Aubrey: Listen, if you were just looking at this graphic without the narrative that is offered by the documentary, it really looks like it's trying to credit Nazis with the heart health of Norway.

Michael: I posted this on Twitter and people were like, this seems unfair that you're posting this out of context. I was like, “It is not better in context.” 

Aubrey: This is like yet another reason that it's good that I'm not on Twitter very often.

Michael: I know. People were yelling at me, and I was like, “I cannot debunk this for you because Aubrey might see it. So, just open your podcast app in like two weeks.”

Aubrey: Chill out. We'll be back in a minute. 

Michael: So, obviously, all of these country comparisons are extremely facile. The first thing he points out is that Kenya had a much lower rate of breast cancer than America in the 1970s. Obviously, the reason why you have less breast cancer in Kenya at the time is because Kenya does not have a healthcare system that is set up to do breast cancer screenings. Ans also, the rates of infectious diseases are significantly higher in Kenya. So, people are not dying of non-communicable diseases because they have more urgent issues that they're dealing with. 

We then go to the extremely low rate of prostate cancer deaths in Japan, where I looked this up. It appears to be the case that prostate cancer rates are lower in Japan. It's genuinely kind of a mystery. What frustrates me about this documentary is that it's actually kind of interesting. It seems to be more related to the fact that a lot more Americans get a surgical procedure called a TURP, which is where they go up through your urethra and cut a little chunk out of your prostate. And as part of this procedure, they usually do a biopsy on your prostate tissue. 

Aubrey: Oh, so we're just checking way the fuck more often.

Michael: Yeah, basically that is the most obvious explanation. There's just a lot more screening for prostate cancer, especially in 1958, which is the year that he refers to here.

Aubrey: Right. This feels reminiscent to me of that 60 minutes clip about red wine. I'm like, “Well, hang on guys, there might be a story here, but you got to adjust for all this other stuff first.” 

Michael: Right. He then takes us to rural China and Papua New Guinea and says that their rates of heart disease are much lower than the US and again, this is true. They also at this time, have 12-year shorter life expectancies.

Aubrey: Jesus hell.

Michael: Mao dies in 1976. China is coming out of one of the most brutal, decades long repressive periods of any country in history. It's just very weird to make this comparison right and talk about China as some utopia of better dietary choices.

Aubrey: All of this also plays into some narratives that are culturally really tempting to a lot of Americans. One of them is one that we've talked about before. It's in a book called Diet and the Disease of Civilization, which is sort of this belief that our diet is evidence that we are part of a fallen society. When these narratives go in a direction that your brain was already headed, when they tell you things that you were already kind of thinking, those are points that are more likely to land for you.

Michael: That takes us to Norway and the Nazis.

Aubrey: Tell me about Norway and the Nazis. Jesus Christ.

Michael: I thought this was super interesting. It is true that the Nazis occupied Norway and confiscated everybody's livestock and immediately imposed really strict rationing regimes. People were so desperate for food that they were like growing food in their backyards. A lot more people started fishing, just like get food from the wild. People were like eating moss and shit. It is true that the dietary patterns of Norwegians changed very significantly and very rapidly during this period.

What the documentary doesn't mention though is what the war did to infectious disease. So, there is a researcher named Broda Barnes who wrote a book called Solved: The Riddle of Heart Attacks and he is looking at this period after World War II all over Europe. You have rapidly rising living standards. People are getting back to normal and they're rebuilding infrastructure. Employment is really high. They're setting up these healthcare systems, setting up welfare systems for the first time. At the same time, you have an explosion of heart attacks. It's like, well, people are doing everything you're supposed to do. They have healthy diets, much better living standards, and yet heart attacks are going up. He starts looking at autopsy data from people in Graz, Austria, and he finds the same pattern that they found in Norway, where there's this huge reduction in heart attacks and then a massive increase. This isn't all of the explanation, but the primary explanation for this effect is tuberculosis.

Aubrey: What?

Michael: Having blocked arteries makes you susceptible to tuberculosis and it makes you susceptible to heart attacks. It increases your risk of both of them. Before the war, most people would just die of tuberculosis. If you had blocked arteries, you get tuberculosis, you end up dying of tuberculosis. You don't live long enough to have a heart attack. After the war, you get treatments for tuberculosis. So, when you get tuberculosis, you get antibiotics and then your tuberculosis goes away. You live a couple more years and then you die of a heart attack because you have all these risk factors.

Aubrey: Well, this is also something that has come up on the show before that you have mentioned, which is essentially like how technologies and treatments are changing around these conditions. We are still talking about heart disease in sort of the way we did in the 80s and 90s and treatments for heart disease and mortality rates and all of that kind of stuff look really different now than they did 30 or 40 years ago.

Michael: Well, what I'm so fascinated by is without any context, you look at Europe after World War II and you're like, “Holy shit, the heart attacks are going crazy.” Like, this is really worrying. But actually, it's good news, because almost every single one of those people would have died of tuberculosis. What that's actually reflecting is a precipitous drop in tuberculosis deaths. But what it looks like from the outside, or if you only look at this one metric, you're like, “Oh my God, we're getting so much less healthier.”

Aubrey: It's interesting, as we're talking about this, I'm realizing how many mortality numbers are just completely and totally decontextualized.

Michael: Totally, I know. This fucked with my brain too. Yeah.

Aubrey: The main way that I feel I encounter mortality numbers in the wild is not unlike this documentary where it's just like big block letters of a big scary number in red but it's not stacked up next to, "Here are some other similar levels of mortality causers." They're not giving you anything to relate it to. They're just saying big numbers at you and the big numbers sound scary. 

Aubrey: This takes us back to Norway. So, what we find when you look into the actual specifics of Norway, and you're not just trying to make a point with a graphic or whatever, is that tuberculosis and other infectious diseases exploded in Norway during World War II. So, this is from a paper about this. It says, “The incidence of infectious diseases increased substantially during World War II in Norway, probably due to the introduction of infectious agents from the large contingent of German soldiers and civilians, up to 450,000, and in addition, 100,000 prisoners of war from Eastern Europe.”

So, basically a huge influx of people into Norway. Some of those people are carrying tuberculosis and other infectious diseases. So, heart attacks go down because people are dying of other things first. They're getting pneumonia. They're getting various other things. Tuberculosis is one of the main causes. There is actually a big outbreak of tuberculosis in Oslo during World War II. But just kind of overall, people are just dying of other stuff. So, just like a rise in heart attacks isn't necessarily bad news, a drop in heart attacks isn't necessarily good news. 

Aubrey: I think again, particularly after having done a couple of years of this show, I now feel so suspect when I see this kind of decontextualized reporting. This one weird trick, and then the graph goes down and you're like, "What?"

Michael: Yeah, I'm way too mortality pilled to watch documentaries like this. I was watching it and it just has the structure of something that's wrong. Anytime, you're like, "World War II and then the heart attacks fell." I'm like, "I think someone's probably written a PhD about this, and it's probably significantly more complex."

Aubrey: Yeah, this is the reaction that I started to have early on when we were doing the show, to headlines with a question mark in it. I'm on to you. We're not doing this.

Michael: So, to return to the film, we then go from Nazis to protein. 

Aubrey: Yeah, the classic progression. 

Michael: There's a whole thing. They do more stuff about how animal proteins cause cancer, but it's all this aflatoxin shit. They do mention very briefly, and I don't know why they don't linger on this more, that vegetarian diets do not mean that you're going to get a protein deficiency. The whole thing of, you need all this protein to survive is basically just like a decades long propaganda campaign by the meat industry. 

Aubrey: Mm-hmm. It feels similar to the fiber stuff. It's similar to vitamin C stuff, where we're really bad at knowing what things have protein in them. Plenty of vegetables, plenty of beans, plenty of-- Generally speaking, Americans eat much more protein than any sort of nutritional guidelines suggest that we might need. 

Michael: Also, there's dozens of studies on this. One of the ones that I found, non-vegetarians are getting roughly double the amount of daily recommended protein, and vegans are getting one and a half times the recommended amount of protein.

Aubrey: Good, good, good.

Michael: And so, for non-vegans, we're getting 15% to 17% of our calories from protein, and vegans are getting 13%. So, it's not that big of a difference. I should say that those surveys are based on the same dumb food frequency questionnaires that we're always criticizing in other diet studies. I don't believe biblically in these numbers, but also, one of the main problems with these food frequency questionnaires is that people underestimate how much they're eating. So, if people are saying that this is how much protein they're getting, they're probably getting even more. And then even if you throw out the food frequency questionnaire stuff, which is totally legitimate, protein deficiencies are just not a problem in the United States. People are not going to the hospital with protein deficiencies.

Aubrey: I'm guessing they're a problem inasmuch as hunger overall is a problem. 

Michael: Yeah, this is what you find in the study. I found a study that is finally just laying it out like brass tacks. It says, “There is a widespread myth that we have to be careful about what we eat so that we don't cause protein deficiency. We know today that it's virtually impossible to design a calorie-sufficient diet which is lacking in protein and any of the amino acids.” So, basically when you look at actual protein deficiency cases, it's almost always people with very rough eating disorders who just are not getting enough food overall. You would legitimately have to try to design a diet that has enough calories but doesn't have enough protein. So, unless you're doing this for a fucking YouTube challenge or something, you're probably fine.

Aubrey: My understanding is that this is the case on a number of nutrients. You don't need to worry about how much riboflavin you're getting.

Michael: Oh, yeah. The only exception I found was that if you're an elite athlete, it turns out you can eat more protein or whatever. But you know that if you're an elite athlete. It's not like you're learning this from an internet listicle for the first time. And the vast majority of the population is not an elite athlete with very specific macronutrient needs.

Aubrey: Michael Phelps isn't listening to this episode going, like, “Oh, interesting, more protein. All right, [crosstalk] good to know.” 

Michael: We then get a clip about the ability of a vegan diet to reverse heart disease. So, I’m going to send you a clip.

Aubrey: Okay. Let's go.

Audio clip: Dr. Esselstyn was getting some powerful data from the research he'd started in 1985. He began with 24 patients, but 6 had dropped out in the first year, leaving him with a total of 18.

The end of five years, we had follow-up angiograms, and eleven of the group had halted their disease. There was no progression and there were four where we had rather exciting evidence of regression of disease.

These results were astonishing. The diet produced something that medication and surgery never had before, actual reversals of heart disease.

Michael: They're again making some very bold claims. 

Aubrey: The underlying logic is like, "You're basically immortal. You will die of old age at 90 something or 100 and something, because nothing's taking you down."

Michael: He's also papering over some fairly weird number stuff.

Aubrey: Yeah. Four cases, yeah.

Michael: This study that he's talking about, he does eventually publish it. I'm getting a lot of this from a woman named Denise Minger, who is one of the only people to take this movie seriously and try to debunk it. She points out that there's no control group. It's self-selected. People are going to this guy who's at this point a very prominent vegan advocate. This is basically just an anecdote ultimately. Even though it's published, it's basically published as a case study. It's not like a randomized control trial or anything. I can't really debunk that. But it's not clear that this really says anything about vegan diets overall. But what's really interesting is that there are actually studies where these kinds of interventions have reversed heart disease. One of the most famous ones is, do you know Dean Ornish? 

Aubrey: Sure. The Ornish diet. 

Michael: The Ornish diet. My mom was on that for years. This was like a huge presence in our house growing up. 

Aubrey: Very big, very popular in the 80s. 

Michael: Yes, He’s basically like the patron saint of low-fat diets. This is the guy telling you to eat carrot sticks. This is why your parents were doing that in the 80s. He has a study that shows people actually reversing symptoms of heart disease. So, this is touted as evidence that a low-fat vegetarian diet reverses heart disease. However, if you read the actual study, it's not just a low-fat vegetarian diet. This is a program where people are also quitting smoking, they're also getting stress management training, and they're also increasing their exercise, getting daily exercise. 

Aubrey: Oh, so it's a full overhaul on how you were being in the world is now very different than how it was before. That's a lot more than just eating less fat in your diet.

Michael: And also, after you have a heart attack or a stroke scare, usually you're extremely motivated to change your lifestyle. So, a lot of these things work for a year or two because people are like, “Holy shit, I'm going to die,” and then they do all this stuff at once. That doesn't mean that a low-fat vegetarian diet doesn't reverse heart disease, but it's like we're doing 10 things at the same time.

Aubrey: I would also say, in that year or two after a cardiac event or after a new diagnosis or whatever, you are extremely motivated to make a bunch of lifestyle changes, but you were also on a more intensive schedule of healthcare.

Michael: Oh, yeah. There's numerous scenes in this documentary where they talk about how these vegan doctors are like, “We're not like other doctors.” And there's a scene where a doctor goes with one of his patients to the grocery store and helps him shop for stuff and is giving him recipes and having him over for dinner, it appears. So, it might not be the veganism. It might be that your doctor really gives a shit about you.

Aubrey: I would say also on this reversal stuff, is just because it's possible for some people doesn't mean that it is likely for everyone or possible for everyone or guaranteed for everyone. But the way that this kind of stuff comes across and the way that it is pitched is this is a sure shot. All of those caveats, which are all context, are all missing.

Michael: I also think it's important to note that it may be the case that vegan diets can help people reverse heart disease, but that's not the only diet that has been shown to do that. There are studies of the Mediterranean diet that have shown that. There are studies of low-fat diets, there are studies of low-carb diets, there's a study of a high-fiber diet.

One of the most interesting things I found was one of the studies showed that people tend to stick with a vegetarian diet longer when they're doing these programs because obviously, the initial burst tends to go away after a year or two. And one of the reasons why vegetarian diets might be good for managing things like diabetes and heart disease could just be that people find it much easier to stick to over the long term because vegetarian diets are fairly entrenched in our lives. You can go to a restaurant and be like, “Oh, hey, what do you have on the menu that's vegetarian?” Whereas if you're on the Mediterranean diet or I'm low carb, there's just a bit more friction.

Aubrey: I will say I think it's easier to be vegetarian take is a very coastal city dweller take, in part because this is one of my favorites. A good friend of mine is vegetarian and works in politics in Montana and ends up at a bunch of fundraising dinners. She will ask for the vegetarian option at said fundraising dinner and will be given chicken. That's vegetarian for Montana. "Oh, it's a bird. You're welcome."

Michael: Yeah. This used to happen when I lived in Germany a lot too, that my American friends would be like, “What are your vegetarian options?” And they'd be like, “Veal.” Psych. [Aubrey laughs] No, I think the baby animals are still animals. Okay, so after this, we then get one of the weirdest clips of the entire movie. So, they're catching up with people who were in this heart disease study, and so we're doing a follow-up with one of the patients and the benefits in their lives.

Audio clip: Anthony and the other male patients also noted another change. 

When you're young, when you're a teenager, you see a female and so on, it gets kind of excited. The first reaction physically, gets attention, raised a flag, I call it. This happened to us. All the other, Dr. Esselstyn's I call them all the guinea pigs, the flag still rises.

Aubrey: What? So, now we're just talking about dicks? 

Michael: So, this dude gets boners. We're talking about this dude and his boner. 

Aubrey: Goddamn it. 

Michael: But he's talking about raising his flag. 

Aubrey: Very patriotic. 

Michael: I was already to debunk this. The thing about a vegan diet reversing your erectile dysfunction is obviously not supported by the data. However, erectile dysfunction is a precursor of heart disease. And so, it's now becoming a thing that they actually tell patients that if you're middle aged and you start getting erectile dysfunction and there's no kind of obvious reason for it, then you should go get your heart checked out, because it's like your arteries closing, and it's something--

Aubrey: It's like a blood flow issue? Yeah, yeah, yeah. This is a thing to look out for. 

Michael: If you're not raising flags. [Aubrey laughs] So, that's basically the end of the documentary. We're only two-thirds of the way into the documentary at this point, but the rest of the documentary is just a bunch of stuff that is true but kind of irrelevant. So, there's a long sequence with an MMA fighter, and he's like, “It's possible to be an athlete and a vegan." I'm like, "Yeah, yes, it is." Okay, there's a whole section about how school lunches suck. Yeah, that's true. There's a very baffling part where he talks about milk being bad for you and milk is poison. There's a really funny chart where they point out that the countries with the highest milk consumption in the world have the highest rates of hip fractures, which is a sign of osteoporosis.

Aubrey: What?

Michael: So, it turns out milk doesn't actually make your bones stronger.

Aubrey: This is some fucking Pete Evans shit. Dairy leaches calcium from your bones was his thing, I believe. 

Michael: I love this as a spurious correlation because all of the countries that have the highest milk consumption, they're all Scandinavian countries, and most of the countries with the lowest milk consumption are tropical countries in Southeast Asia. In debunking this movie, people point out that all of the countries with high milk consumption have very cold winters. And one of the main reasons why people fracture their hips is falling on the ice. So, you just, in Thailand, have a lot fewer hip fractures than you do in Norway, which has nothing to do with milk consumption. It's just there's a reason people fall down in Scandinavia.

So, then the worst, by far the worst section of this movie is there's a lady who's a marathon runner, and then she's diagnosed with breast cancer. They're like, “Oh, she was told to get radiation and chemotherapy. But instead, she went on a vegan diet, and now she's running Iron Mans.”

Aubrey: Right. We're back in sort of Gerson therapy adjacent territory. 

Michael: Yeah, this was where-- I mean, not that I had a lot of confidence in this documentary, but I was like, “This is really irresponsible.” Vegan diets are fine, but don't tell people that they fucking cure cancer. What the fuck is wrong with you?

Aubrey: I would say I feel sort of shades of gray that way about most dietary interventions into most health conditions. If someone is telling you and is not presenting pretty hard and fast data that X, Y, or Z dietary change means that you cease to have a chronic health condition, all of this shit just needs to be tempered and presented in context in order for us to understand it properly.

Michael: But then, this gets us to what I want to spend the rest of the episode on, which is the years long debate about whether a vegetarian diet is good for you.

Aubrey: Oh, just full stop. Just like, is it healthy, period. 

Michael: Are you healthier eating a vegetarian diet than not eating a vegetarian diet? This is the core claim of this movie.

Aubrey: Let's do it.

Michael: So, to talk about this, we have to talk about vitamin E. Vitamin E is a now notorious antioxidant. In the 60s and 70s, there were a bunch of mouse studies that showed that this helped oxidate the bloodstream and could reduce plaque in their little mouse hearts. After this kind of very preliminary hypothesis generating stuff on animals, people start doing these observational studies on humans. Vitamin E is found in-- like, it's in sunflower oil and almonds and peanut butter and all kinds of stuff. So, they start doing these big cohort studies where they ask people what their diet is and what kind of health markers they have, how early they're dying, etc. And so, again and again, studies are finding that people who consume more vitamin E live way longer. This is starting to look pretty strong in the 1990s. It's like, "Well, it's happening in animals. It's happening in people. So, we should probably start giving people supplements for vitamin E."

So, in the 1990s and 2000s, doctors start giving vitamin E supplements to patients, especially patients who have had some cardiac event. So, people who are recovering from heart attacks start getting vitamin E supplements. The daily recommended amount of vitamin E is 22 international units and doctors start giving patients either 400 or 800 international units.

Aubrey: Holy shit.

Michael: 20 to 40 times the daily amount.

Aubrey: Jesus.

Michael: And so, after this wave of animal studies, after this wave of observational studies, we start getting randomized control trials of people who are taking vitamin E and people who aren't taking vitamin E. And it turns out that vitamin E has no effect and for some people, vitamin E actually increases the risk of heart attacks. These are not large effects. But people who take large doses of vitamin E are 13% more likely to have heart failure in one study.

Aubrey: Oh, wow.

Michael: So, there's now been this huge turnaround on vitamin E, and the entire field is like, "Oh, fuck. We really got this one wrong. We're basically giving people large doses of this thing that there really is no evidence for at this point." So, people have now gone back and have done this sort of like, what happened? How did this whole catastrophe take place with vitamin E? What they've identified is something called healthy user bias. [Aubrey laughs] In all of those observational studies, the people who were getting more vitamin E were people who were eating more almonds, eating more vegetables, they're getting more fiber, they're basically eating a better diet. Those foods happen to have vitamin E. But it wasn't the vitamin E that was making those people healthier. It was all of the other shit that they were doing. 

Aubrey: Yeah. Which also probably correlates to higher socioeconomic status. It also probably correlates to not having other disabilities is my guess. I mean, I think about this often with celery juice too. If you're a person who can afford a juicer and has the time in the morning to juice 16 ounces of celery and drink it and then wait a half an hour before you eat anything else, there's all this other stuff that's sort of loaded into that. It's not just a matter of like, “Oh, any person who drinks this celery juice will have this effect,” or whatever.

Michael: This form of bias is a huge existential problem in these kinds of studies. One of the large effects that I found in other various meta-analyses is that people who brush their teeth regularly have 30% lower mortality than people who don't brush their teeth. What that's covering is not necessarily that brushing your teeth extends your lifespan. People who brush their teeth are more likely to engage in all kinds of other healthy behaviors. This turns out to be the central problem with comparing the health of vegetarians to the health of non-vegetarians.

If you just look at the raw data, vegetarians and vegans have way lower rates of everything. Diabetes, strokes, cancer, they live longer. Basically, any health thing that you can name, vegetarians do better and vegans do even better. But that doesn't necessarily mean that it's the diet that is doing it, because only around 5% of the population is vegetarian or vegan, and the non-vegetarians is everybody else.

So, you're basically taking a very small subset of the population who are way more health conscious in a million ways. Vegetarians get more physical activity than non-vegetarians. Vegetarians are less likely to smoke, they are less likely to drink, they're more educated, they tend to be from more affluent backgrounds. Although they actually have lower incomes than the population at large, but that's mostly of just the fact that they're younger. And then, one of the things that this documentary does that I think is a very interesting bait and switch is throughout the documentary, they talk about the benefits of a plant-based diet, but they always add this little modifier. They say, "a whole-foods, plant-based diet."

Aubrey: Yeah, well, that's a big fucking difference.

Michael: But then, they don't define what the fuck whole foods means. And in these awful little montages, they have this B-roll of like a family at McDonald's and they're sitting there eating French fries, and it's very clearly designed to be stigmatizing. But also, French fries are vegan. French fries are pretty close to a whole food. You chop up the potato and you cook it. What they're basically doing is very clearly promoting a vegan diet. The whole movie is like, "Milk is poison, meat is poison, etc." But they're also giving themselves this little asterisk of, like, “Well, if you're a vegan and you still get cancer, the foods you ate weren't whole enough.”

Aubrey: Yeah. That's the difference between the kind of veganism that eats at vegan restaurants and drinks a bunch of green juice and all that sort of stuff. And then, your vegan roommate in college who kept yelling about how Oreos are vegan. Where you're like, "Yeah, yeah, yeah,” there's a way to eat in a way that people sort of associate with a lack of health for kind of any way of eating.

Michael: Yeah, exactly. So, if you look at surveys of the food behavior of vegans and vegetarians, it's like they eat less fat, they eat less sugar, they eat more fiber, they eat fewer calories overall. They eat foods with higher nutrient density. I'm not married to the idea that any of these other things are necessarily explaining the differences. I don't think there's a diet that is best for everybody, but it's like there's almost no one who has the same patterns as the average American but doesn't eat animal products. The fact that vegetarians and vegans live longer and have all these better health markers, maybe that means that vegetarian diets are healthier. We can't rule that out, but we can't say it with any confidence either, because it's like there's 15 or 20 differences between vegetarians and non-vegetarians. 

Aubrey: Sure. I mean, it would also be interesting to look at people who are vegetarian for religious reasons. Like, I'm thinking of Hindus. Okay, does that play out differently or the same? 

Michael: Yeah. It's very weird to me that the vast majority of studies on this only look at UK or US vegetarians when 40% of the population of India is vegetarian.

Aubrey: Oh, interesting.

Michael: Although it's also an interesting demonstration of how difficult this is, because in rich countries, being a vegetarian is a sign of high socioeconomic status. It's like Reese Witherspoon in Big Little Lies. But in poor countries, vegetarianism is associated with low socioeconomic status because when you're super poor, you're eating basically just rice or potatoes or some other super basic starch because you can't afford anything with higher protein or higher fat. And so, as people move up the income ladder in poor countries, what tends to happen is they don't actually eat more calories, but they eat more higher end food, things like meat and eggs and dairy. So, it also speaks to how this is always couched as a biological thing and how this affects the body but it's extremely social.

Aubrey: Right. The idea that we could just cleanly say this is straightforwardly because of vegetarianism or because of a fully plant-based diet feels like, again, I'm not sure that we've eliminated everything else just yet.

Michael: Well, one thing I will say, I called up Catherine Flegel to help me with this episode because we've kind of become pals since we did an episode on her a year and a half ago. 

Aubrey: I love everything about this. 

Michael: I know. She's like an actual methodology queen. I'm joking about my methodology queen status, but she actually knows what she's talking about. So, I check in with her when I have a technical question. 

Aubrey: We're like the fantasy football of methodology. You know what I mean? Like, "No, no, no."

Michael: A lot of the studies on vegetarians versus non-vegetarians do use statistical controls. So, we've controlled for income, we've controlled for age, we've controlled for gender, etc. So, statistical controls allow you to compare like for like. Vegetarians on average are much younger than non-vegetarians. So, if you're going to do a study, you have to control for age because otherwise it's going to be like, "There were no heart attacks," because young people don't really have heart attacks. So, controlling for age allows you to compare 60-year-old vegans and 6-year-old non-vegans, and rich vegans and rich non-vegans. You can hold everything else constant so you're comparing like for like, which is great.

However, you can only control in that way for the variables that you gather. So, if you have data on socioeconomic status, then you can control for it. If you have data on gender, you can control for it. Very few of the studies that I found controlled for health insurance status.

Aubrey: That seems like a big one, dude.

Michael: I know. One of the weirdest findings, there's all this research showing that vegans and vegetarians have higher rates of depression and anxiety, but I don't think that's the fucking diets. I think they're more likely to have healthcare.

Aubrey: Sure. A condition of existence at this point is a certain percentage of people are just going to be depressed and anxious and the difference is who can access treatment and who can't. 

Michael: Right. So, I don't think that means anything. But then, I also don't think that the health stuff really means anything either, because you can't control for all of the behaviors that distinguish vegetarians from non-vegetarians. This is where the vitamin E comparison comes in. A lot of those studies on people who eat vitamin E live longer, they did control for things like socioeconomic status and gender and age and all this other stuff that you're kind of supposed to control for, but there's some residual stuff that you can't control for because you don't have every single piece of data that you would need--

Aubrey: To control for, yeah, yeah, yeah.

Michael: I read a really interesting article about the problem with observational studies, it used to be that the threshold for publishing these kinds of studies was like, you would need a three to four times greater risk to publish something. People who eat apples are four times more likely to have heart attacks or whatever. A lot of the studies coming out about these kinds of risks and a lot of the studies on vegetarians and vegans, it's like, “Oh, you're at 10% higher risk of a heart attack.”

Aubrey: Yeah, which your overall risk for a heart attack was like 1%. And now, it's 1.1%. 

Michael: Yeah, it's very small. And then, these small gradations are easily swamped by all the shit you couldn't control for. Another one of the articles that I looked at pointed out that smokers are 20 times more likely to get lung cancer than non-smokers. You can say, okay, smokers also have some characteristics that make them different. It's a minority of the population. There's other things that distinguish them. But if we're talking about a 20 times difference, it's like, “Oh, well, people who smoke don't get as much sleep.” All right, maybe that knocks it down to like 19 times more likely. 

Aubrey: Yeah. But it's like a pretty decisive impact. 

Michael: So, much of this whole field of observational studies, it's tiny effects. Given everything else we know about the muddiness of this data and the bad track record of these fucking studies, we just can't really say anything.

Aubrey: Well, there's also a bunch of stuff that there have been illustrated links between these things and heart disease. Things like experiencing racism or experiencing weight stigma. All of these things are linked to some kind of heart health conditions. You're not going to be able to control for that stuff necessarily either. There's just a bunch of stuff that structurally is going to be too difficult to build into any one study.

Michael: I mean, I also want to say that it also is plausible to me that, I don't know, vegetarian, vegan diets are better for you. None of this rules out vegetarian and vegan diets-- and people, Aubrey, people who go out of their way to dunk on vegetarians online are some of the saddest fucking people I've ever come across.

Aubrey: Just mind numbingly boring.

Michael: So boring. I came across this first when I was researching our Carnivore Diet episode where there's these weird fucking meat influencers who make up these vegans to dunk on. They're like, “Vegans don't want to admit, man.” It's like, "Dude, just eat meat or don't eat meat, man, but shut the fuck up about what other people are doing."

Aubrey: Fucking weird. 

Michael: Jesus Christ. 

Aubrey: There's a real strain of this in anti-fat activist stuff where they'll just, make up shit that they're like, “Fat activists say it's fat phobic to have a decent resting heart rate.” You're like, “No one has ever said that.”

Michael: "Do what you want to do, man." I watched this presentation by this academic lady who did the Myth of Vegetarianism or something, and she was like, “You say you care about animal rights, but what about the animals that are killed to grow crops?”

Aubrey: What?

Michael: [laughs] I don't think that vegans are pretending that their actions have no effect on any animals whatsoever. I think it's just really easy to opt out of the worst forms of animal torture, and people are doing that, and it's such a fucking weird thing to do with your time, to criticize other people who are trying to have less of an impact on living creatures and the planet. It's like, “You're just as bad as me.” Well, we're all kind of bad. It just seems like a weird thing to be proud of. 

Aubrey: It's just three cattle ranchers in a trench coat. 

Michael: Five million Joe Rogan listeners in a trench coat, but yes.

Aubrey: Jesus Christ.

Michael: So, I want to end with a quote from the Annals of Internal Medicine. This is one of the only editorials I found that says what I have been thinking for many years now.

Aubrey: Ooh.

Michael: It's an issue where they go over a lot of these meta-analyses of red meat. This is during the fucking red meat wars in 2019 when a bunch of studies come out about this. This editorial says, “It may be time to stop producing observational research in this area. These meta-analyses include millions of participants. Further research involving much smaller cohorts has limited value. High quality, randomized control trials are welcome, but only if they're designed to tell us things we don't already know.”

I love to see this, that people in the field are like, “Let's not do this anymore.” Every single time one of these fucking studies comes out, it's like, “Red meat will kill you. Red meat will save you,” whatever it is, coffee, breakfast, anything, we know how these things are going to be framed in the media, and we know how they will be received by readers. The only reason you click on a headline about, “Drinking coffee in the morning causes cancer. Drinking coffee in the morning cures cancer,” the only reason to read those stories is to adjust your own habits. The general population is not interested in these studies for biological, epidemiological, population level reasons.

Aubrey: Nor are we reading the original text of the studies.

Michael: Which always say we cannot determine cause, yes. 

Aubrey: Right. All it's doing is fanning the flames of the closest sort of diet world gets to culture wars. But this is a road to nowhere or it's a road to where we already are, is maybe a better way to put that.

Michael: The whole thing is this quest for the best diet. I think that is a pointless quest. Are vegetarian diets better for you? Seems like a very simple question, but it turns out the science that we have available to us can't really answer it. And that's basically going to apply for any kind of dietary pattern. If you are just happier on a vegetarian diet than not on one, then that works great for you, and you should do it. For other people, it's going to be Mediterranean. For other people, it's going to be low fat. For other people, it's going to be nothing. I don't know that more of these studies is really doing very much for us.

Aubrey: Okay, so what I'm hearing is that I should go vegan and paleo at the same time.

Michael: Just hearing you say that made me raise my flag.

Aubrey: [laughs] No, Michael. Oh, no. I'm going to HR.

Michael: That just happened.

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