This is a transcript of the Gastropod episode To Eat or Not to Eat Meat, first released on February 14, 2017. It is provided as a courtesy and may contain errors.

GIDON ESCHEL: People just say things, assert, you know, with rarely pausing to bolster their argument by any persuasive means known to humanity. So we started from one of those assertions, which is that it is better, environmentally speaking, to eat plants than it is to eat animals.

NICOLA TWILLEY: That’s something you hear a lot: we should all be vegetarians because that’s how to save the planet.

CYNTHIA GRABER: That’s not the only claim you’ll hear about giving up meat. Another one is that we’d all be much healthier. Fewer heart attacks, less cancer, longer lives.

TWILLEY: And that’s before you get to the moral arguments against taking animal lives and this whole idea of animal rights.

GRABER: Those are the claims. But what’s the evidence? That’s just what we’ll be looking at this episode. You’re listening to Gastropod, the podcast that looks at food through the lens of science and history. I’m Cynthia Graber.

TWILLEY: And I’m Nicola Twilley. But before we dive into literally millennia of arguments about the pros and cons of a meat-free diet, we have a quick favor to ask.

(PRE-ROLL)

(MUSIC)

TWILLEY: Whether or not to eat meat is a very long, very intense, and very personal debate. It’s not something we can give you a final right or wrong on. We wouldn’t dare!

GRABER: Instead, this episode, we’re going to look at all the claims people have made about why you should give up meat, and the arguments for and against those claims. We’ll go through the history of each argument and try to figure out whether the claim is true. But this episode is not absolutely everything there is to say on the topic—we cannot cover every argument ever. The ones we’re going to discuss are the main ones. The ones you hear all the time.

(NATALIE PORTMAN ON THE DAVID LETTERMAN SHOW)
(INTERVIEW WITH MOBY)

TWILLEY: OK, first big claim: it’s immoral to eat meat, because we don’t have the right to take animal’s lives. That’s violent, and violence is bad. This argument goes deep in a bunch of different religions.

JOANN DAVIDSON: Most of the early traditions of world religions such as Hinduism and Buddhism all had a strong strain of nonviolent diet teaching in their ancient teachings. There are different motivations. But it’s interesting they all believe in ahimsa, which is a fundamental teaching of nonviolence to life.

GRABER: JoAnn Davidson is a theology professor at Andrews University Theological Seminary in Michigan.

TWILLEY: So here’s the thing about this claim that eating meat is immoral: it’s a belief. If you believe, it’s true; if you don’t, it isn’t. But what’s interesting is how this question came to be so central to so many different groups and religions.

COLIN SPENCER: You see, meat became very sacred right at the earliest time that we can go back.

GRABER: Colin Spencer wrote a book called The Heretic’s Feast: A History of Vegetarianism. And one of the things he points out is that almost all religions grapple with meat in some way. His reasoning for why is that back in the beginning of our evolutionary history as humans, hunting big game took a group. And it took a group to feast on big animals before they went bad. And so early humans developed group rituals around meat.

TWILLEY: And then those rituals developed into a deeper set of questions around what is a life and do we have the right to take lives. And so meat become central to most world religions in one way or another. Think of animal sacrifices.

GRABER: The religion that’s best known for practicing vegetarianism is Hinduism. It didn’t start out that way, but about 3,000 years ago, the doctrine of reincarnation became part of Hinduism—and then so did vegetarianism.

TWILLEY: Not all Hindus are vegetarian, both then and now. But the logic is, killing animals is violent, and that is like a black mark against your future reincarnation. The same kind of logic is found in Buddhism.

GRABER: But not all Buddhists are vegetarian, either.

TWILLEY: The strictest religion when it comes to the belief that eating meat is bad, no ifs or buts, is Jainism

PURVI SHAH: It’s really central, you can’t be a Jain and not be a vegetarian.

TWILLEY: That’s Purvi Shah, a Jain… and a Gastropod listener!

SHAH: I like listening to Gastropod while I’m cooking or while I’m eating, anything that relates to food or stuff like that.

GRABER: For Purvi, whatever she’s cooking, it’s vegetarian. Jainism developed in India after the dawn of Hinduism.

SHAH: And Jains believe that every living thing has a soul and so everything should be treated with equal respect. And so that is why we’re all vegetarians.

TWILLEY: The strictest Jains won’t eat vegetables like broccoli or cauliflower because they tend to have insects hiding in them. And no root vegetables at all, that’s taking away the lifeblood of the plant.

GRABER: And strict Jains won’t eat after dark because they might inadvertently eat something that’s alive.

TWILLEY: These three religions—Hinduism, Buddhism, and Jainism—they’re Eastern religions. And that’s how I thought of vegetarianism and nonviolence and reincarnation—as Eastern ideas. But it turns out I’m wrong. There was an ancient vegetarian nonviolent reincarnation-based belief system in the West.

SPENCER: Well, the vegetarians were known right up to the 19th century—I mean Shelley the poet called himself a Pythagorean.

GRABER: Pythagorean—or pythagorean, as I’d say it in America—that sounds an awful lot like the Pythagorean theorem. Like, you know, math class, figuring out the angles in a triangle.

TWILLEY: Same dude.

SPENCER: Pythagoras is mostly known to us because of the famous triangle, which is taught at school. He lived between 500 and 600 B.C. and he taught mathematics. He was basic to our knowledge of music. And he looked at the stars and planets and he worked out in fact then, that we went round the sun.

GRABER: Two thousand years before Galileo did!

SPENCER: So he was just a wonderful kind of genius really.

TWILLEY: A Renaissance man, two thousand years ahead of his time.

SPENCER: I forgot add the most important bit which is that he was a vegetarian, the first individual vegetarian we know of. And so at the school they were all vegetarians, and then after his death it spread into groups in the Greek society.

GRABER: Like the Hindus, Pythagoras believed in reincarnation. And while nobody knows exactly how he got these ideas, he did travel widely. He visited Egypt and was influenced by thought there. Colin thinks that Pythagoras might have actually visited India, too. That’s just speculation. Still…

SPENCER: He believed that after death we moved into other bodies and animals and he once recognized a friend’s voice in a dog that he heard barking. But so you might—well, if you eat a cow you might very well be eating your grandmother.

TWILLEY: Long term, Pythagoras’s ideas didn’t catch on in Europe in the same way that reincarnation and vegetarianism did in the East. But still, if you were a vegetarian in Europe, all the way up to the 19th century, you didn’t call yourself a vegetarian. You called yourself a Pythagorean, like Shelley.

GRABER: So there were vegetarians, these Pythagoreans who chose not to eat meat because they believed it was wrong, they were there in Europe. They existed. It just wasn’t a major movement.

TWILLEY: Because Christianity was the mainstream religion in Europe, and Christianity had taken a very different position on the morality of eating meat.

SPENCER: But you see Christianity, because of the Old Testament, believed that all the animals were put in the world for the sustenance of man. And so God has a specific purpose for the animals: that they should be eaten by men. That was their argument. So the Christian church, especially through the Middle Ages, believed so passionately that you were almost wicked, you were wicked not to do what God wanted, which was to eat the animals.

GRABER: It could have been different in Christianity. When Christianity was still being formalized as kind of what we know today, there were a few different strands of thought.

TWILLEY: One of those groups of very early Christians was called the Gnostics. The Gnostics allowed women to become priests as well as men, and they preached the importance of letting go of the material world and fasting and all sorts of ascetic beliefs. And one of their doctrines was not eating meat.

GRABER: But as Christianity became more set in stone under Paul, these Gnostic beliefs kind of died out. Gnostics were actually condemned as heretics.

TWILLEY: It’s funny to imagine if that version—the Gnostic version—of Christianity had triumphed instead.

SPENCER: The whole world you see would be almost vegetarian really.

GRABER: But that’s not how things turned out. Human dominion over animals was really central to Christianity, and to Europeans.

TWILLEY: That all started to change in the 17th century. Tristram Stuart is the author of a book called The Bloodless Revolution, all about vegetarianism in Europe from the 1600s onward.

TRISTRAM STUART: Two things were happening simultaneously in seventeenth-century Europe. Firstly there was a sudden onrush of interest in the culture of Indian vegetarians and their religious beliefs. Travelers from around Europe went to India and wrote with increasing accuracy and curiosity about the vegetarians that they were encountering—Jains and Brahmins—and why they abstained from eating meat.

GRABER: At this time, it’s not just that Europeans are traveling the world and landing on new continents and encountering new people. This is also the time of the scientific revolution. And so Europeans are also discovering new ways to see the world. All of this is making them question some very basic beliefs. One of those beliefs had been that animals have no feelings.

STUART: People came to analyze the nervous system and they found that the nervous system of animals and the nervous systems of humans are really completely indistinguishable, in so far as their operation is concerned.

TWILLEY: In other words, animals have feelings too. They can suffer. They are much more like us than we thought. And once you realize that, you have to rethink how you treat animals and whether it’s right or wrong to take their lives.

GRABER: But while scientific advances in anatomy provided arguments against taking an animal’s life, other scientific advances made that argument a little murkier.

STUART: The vegetarian idea that you could go through life without killing any animals was blown apart by the discovery, with the use of the microscope in the seventeenth century, that there were millions of microscopic animals that were living on the lettuces that the vegetarians wanted us to eat instead.

TWILLEY: All these new ideas—new science, encounters with entirely different civilizations and landscapes—it all throws European thought into a ferment. And out of that ferment, you get new political ideas.

STUART: Famously, at the time of the French Revolution, when the idea of enfranchising ever greater swathes of the human race in terms of, you know, having them have democratic rights and representation.

GRABER: Famous books were published, on the rights of man. And then on the rights of women. People are arguing that slaves have rights.

SUART: And then you get your vegetarians who say, look, the very same arguments that you’re making for respecting humans can be made for the argument for respecting the rights of animals.

TWILLEY: These same centuries-old arguments persist today—you have well-known vegetarians like Peter Singer and Jonathan Safran Foer saying that animals have rights and so it’s immoral to eat meat.

GRABER: But there are other ways to look at this question of morality. Animals die in all forms of agriculture. Strawberry growers sometimes shoot deer to keep them out of a strawberry field. And pesticides sometimes kill rodents, too.

STUART: And you cannot produce food, you cannot eat food, without doing some sort of violence. Indeed, you could summarize the argument as eat is murder, not just meat.

TWILLEY: Even Jains struggle with this. How are you supposed to think about the living microbes in yogurt, you know? But so if it’s impossible not to cause some violence with your diet, then the moral argument around vegetarianism really ends up being about how you see the place of humans in nature.

STUART: So these these two historically divergent views of nature, one, man is part of an ecosystem, the other man is kind of the sympathy bearer that needs to look after animals.

GRABER: To the ecosystem people, eating meat can be okay. It’s part of nature. We’re part of nature. There can be ways to eat meat and do so morally.

TWILLEY: And to the sympathy bearers, each life is precious, and we, as humans with the power of rational thought, we have a responsibility not to cause suffering and death.

GRABER: So the original claim that we started this section off with: vegetarianism is morally better because it avoids causing suffering and death. We started off saying this is a belief, and, honestly, we’re still there. This isn’t something that we think you can say is either right or wrong. To me, and frankly to both of us, there’s a lot of grey here. I do believe that causing unnecessary suffering is wrong. And that’s one of the main reasons why I’m totally against factory farming of animals, which is how most meat is raised. But personally, I think that as long as animals live a good life, it’s not then immoral for them to become food, too.

TWILLEY: Yeah, me too. And that decision, for me, really does boil down to whether you think we humans are just part of nature, part of the natural cycle, or whether we somehow exist a little outside of it, with different responsibilities. You can defend both positions. I’m on the inside nature side of the argument personally—I see meat-eating as part of humans’ place in the larger ecosystem—but you’re not wrong if you don’t. It’s a worldview thing.

GRABER: This morality question is insanely tough. Entire books have been written on this, and we’ve left out a lot of nuance. Hopefully our next claim will be a little easier to investigate.

TWILLEY: Yes, indeed. A vegetarian diet is healthier.

(ALICIA SILVERSTONE VIDEO)
(BILL CLINTON ON THE ELLEN DEGENERES SHOW)

TWILLEY: That’s the claim. Is it true?

GRABER: And, just like morality, this question has roots in history, too. The debate over whether it was healthier to be a vegetarian also raged in the 1600s and 1700s. Remember how scientists were comparing human and animal anatomy and discovering that we both shared nerves? It wasn’t just the nerves they were comparing.

STUART: It may surprise listeners to know that one of the really big questions that many scientists tried to answer is whether humans were anatomically equipped to digest and consume meat. A lot of attention went on to the structure of our teeth and whether our teeth were more like that of, for example, sheep than of cats. And obviously with our heavy predominance of molars there was a strong case to say we had herbivorous jaws and herbivorous teeth and not carnivorous ones, we didn’t have the sharp fangs of a lion or a tiger. People went into our guts and compared them in particular to that of the great apes. The belief was that they were our closest relatives, that they were herbivorous, and that we shared most of our anatomical features with them. And that again was seen as evidence that the human anatomy was not originally designed for meat consumption.

TWILLEY: This argument is one you’ll hear today, but flipped. In the 1700s, scientists were saying that we were primarily designed as herbivores. Today, you’ll hear people saying that our teeth and our guts are different from apes who eat a vegetarian diet, and so eating meat is what makes us human.

GRABER: In fact, some people today argue that eating meat is what led to us having bigger brains. And of course bigger brains means tools and language and culture and everything.

SPENCER: Well, that’s an entirely erroneous belief. If it was true ,then the big cats would be the top species in the world because they’d be solely eating meat.

TWILLEY: I mean there’s a fairly obvious response to this debate. We’re not designed as carnivores or as herbivores—we’re a little bit of both. In other words, we evolved as omnivores. Our ancestors were opportunistic, and they ate what they could. So the design argument is not going to decide things one way or the other.

GRABER: To go back to the sixteen and seventeen-hundreds, one reason the debates about health are raging is that doctors are seeing some pretty serious widespread health problems—things like gout and being overweight are on the rise, along with rising wealth.

TWILLEY: Basically for the first time, more people than just royalty and the aristocracy could afford to eat meat regularly, in large portions. And so they did.

STUART: I mean, meat was associated with good nutrition, high value nutrition, and  pretty much everyone who could ate as much meat as they could afford.

GRABER: Scientists weren’t sure that it was even possible to live without meat. But this is the time that Europeans are coming into contact with millions of vegetarian Indians. European Pythagoreans found the existence of their Eastern counterparts deeply encouraging.

STUART: And the vegetarians seized on the fact that there were millions of Indians over there surviving very happily without ever consuming meat, as proof that not only could you survive, but indeed the longevity of Indians was often cited as proof that vegetarian diet was healthier.

TWILLEY: And, remember, this is also the time when science is making huge leaps forward. And people are starting to understand nutrition a little better. And so suddenly vegetables actually have value—you need vegetables.

STUART: And so the idea of this meat-rich diet that middle classes and affluent in Europe were subjecting themselves to, and all the diseases that came in its wake, things that we might call obesity now for example, could be cured by going vegetarian. And a band of doctors—indeed, some of the mainstream doctors at the time—were routinely prescribing an abstinence from meat.

TWILLEY: This claim for a vegetarian diet being healthier—it gets more and more popular over time. To the point where it actually kind of takes over as the main argument for being vegetarian in West. Rather than the moral argument.

GRABER: For example, in America, Bronson Alcott—he’s the father of Louisa May Alcott who wrote Little Women—he was a famous early vegetarian in the 1800s because of equality. He’s anti-slavery, he’s pro-women’s rights, and he believes that vegetarianism is morally right, he used the arguments that we talked about at the beginning of the episode.

TWILLEY: But then by the time the American Civil War was over, and John Harvey Kellogg—the father of your corn flakes—he was the voice of vegetarianism in America. And his whole thing was health. He ran a sanatorium where people came to eat his weird vegetarian meat substitutes in order to achieve physical perfection. It was about self-improvement, not improving the world.

GRABER: And this is the claim that we’re investigating now. Is eating a vegetarian diet actually improving yourself? Is it better for you than eating meat? Was Kellogg right? JoAnn told us that one group that’s been studied is the Seventh Day Adventists. They’re a Christian group that encourages vegetarianism to improve physical and spiritual health.

DAVIDSON: There’s this ongoing health study showing how they have much lower incidence of cancer, much lower incidence of diabetes and heart disease.

TWILLEY: What? Do we actually have a clear cut answer on this one, for a change?

GRABER: Well, no. Like everything we cover, it’s not quite so simple. But before we get into the arguments, we have some news from our sponsors.

(MIDROLL)

TWILLEY: So JoAnn told us that studies on thousands of Seventh Day Adventists seemed to show that vegetarians and vegans had lower mortality rates than meat eaters. And coming from the other angle, there are also plenty of studies showing that meat is bad for you.

GRABER: Marco Springmann is a researcher at Oxford University who did one of those studies. It took a big-picture look at all the research around meat-eating.

MARCO SPRINGMANN: For example, we know from our large observational studies that the consumption of red meat increases your chance of getting coronary heart disease by about 25 percent ,of stroke by somewhere around 10 to 15 percent. Colorectal cancer by the same amount and also type 2 diabetes by a similar amount.

TWILLEY: Statistics, statistics. What do those percentages actually mean?

GRABER: Well, Marco and some other scientists tried to forecast out to 2050. He took studies that have been done on heart disease, and on cancer, and on diabetes, and the connection to diet. And he extrapolated out from them. He calculated how many fewer people would die if people ate what the dietary guidelines say we should eat, which is less meat than we eat today, or if they ate a vegetarian diet, or if they ate a vegan diet.

SPRINGMANN: So we found the you could reduce diet-related mortality the more the more plant-based you go. So in the dietary guidelines scenario we estimated that about five million lives could be saved in 2050. In the vegetarian scenario, about seven million lives. And in the vegan scenario, about eight million lives.

TWILLEY: Those are big numbers. Marco is saying that, by 2050, seven million fewer people would die of diet-related diseases each year if we all ate a vegetarian diet.

GRABER: OK, so we have vegetarians living longer and with a lower risk of heart disease, and we have meat eaters—even those who follow a healthy diet—more of them are dying from heart disease and cancer and other chronic diseases, according to Marco. This seems like clear-cut evidence that the health claims people make for vegetarianism are right, no?

FRANKIE PHILLIPS: So, I’m Dr. Frankie Phillips. I am a registered dietitian based in the south-west of England and my area of expertise is vegetarian nutrition.

TWILLEY: We thought it would be a good idea to check in with someone who’s spent a lot of time studying exactly these questions. It turns out that the Seventh Day Adventist study results, showing that vegetarians are so much healthier? Frankie says that there are other factors that might contribute to them living longer than meat-eaters, apart from just being vegetarian.

PHILLIPS: So they might have a conscious reason for eating more healthily and being vegetarian is part of that whole spectrum of being more healthy. And we know that if people are more concerned about their health then they’re probably not smoking tobacco, having a moderate alcohol intake, they might be taking more physical activity.

TWILLEY: So that might be part of why vegetarians seem healthier in the studies. As people, they’re just more health conscious in general.

GRABER: And those meat-is-bad studies that Marco was quoting? There are some criticisms of those, too. One is that the studies don’t separate out processed meat like pepperoni and bacon from unprocessed meat like a steak or pork tenderloin. Because other studies have shown that processed meat seems to be worse for you.

TWILLEY: And those meat-is-bad studies—they also lump together grass-fed beef with industrially raised, grain-fed beef, for example. But there’s good research showing that grass-fed has healthier fats. So there’s definitely some nuance missing there.

GRABER: That said, there are some reasons why vegetarians might in fact be healthier, in addition to going to the gym and not smoking.

PHILLIPS: We know that people who are vegan do tend to have much higher intakes of fiber. And fiber is really useful because it helps to ensure a healthy gut and it can also help us to feel fuller, so we might not perhaps eat quite so many calories. And we know that vegans tend to be leaner, as well, than meat-eaters and other vegetarians.

GRABER: Fiber isn’t the only good thing in vegetables and whole grains—there’s lot of great nutrients. And there’s lots of science to support the health benefits of eating lots of vegetables. But Frankie said there might be some health problems with the vegetarian diet, too.

PHILLIPS: The main foods that we get from from meat and and fish include iron and some of the B vitamins.

TWILLEY: Animal-derived foods are not the only source of iron, as Popeye will tell you. But the kind of iron you find in spinach and beans and so on—that’s not as easy for your body to absorb.

GRABER: Still, most people can get enough iron in a vegetarian diet if they pay attention to what they’re eating. But there’s another nutrient that we get from animal products that’s impossible to get if you don’t eat meat, eggs, or dairy. And that’s Vitamin B12.

PHILLIPS: Now, Vitamin B12 is needed for good blood formation and for nerve function. And so without it then there can be quite severe repercussions. If you’re including eggs still and including dairy foods then you will still be having some of that B12 in your diet and we only need a minuscule amount, a really tiny amount of vitamin B12 to stay healthy. So if you’re vegan your diet is going to be completely devoid of Vitamin B12, if you don’t look for sources which are fortified with the vitamin.

GRABER: Vegans have to rely on getting B12 that’s made by bacteria and then added to cereals and nut milks, or taken as a supplement.

TWILLEY: And Vitamin B12 deficiency is bad if you’re an adult, but it’s really, really bad if you’re a fetus or a growing kid. Vegan kids have been hospitalized with deficiencies. Which is why last year, a super right-wing Italian politician called Elvira Savino introduced a bill into Italy’s parliament, to send parents who raise their kids vegan to jail.

GRABER: Elvira says it’s reckless and dangerous eating behavior for a kid.

TWILLEY: But Frankie the British nutritionist does not agree with Elvira the fascist.

PHILLIPS: It’s quite easy to have a vegan or vegetarian child brought up and to make sure that they have a nutritionally balanced diet but there are a few areas where a little bit more concern, a little bit more care needs to be taken.

GRABER: So kids can be okay on a vegan diet if their parents are careful about nutrition. But what even earlier? Vitamin B12 is crucial to a developing fetus.

TWILLEY: The fetus needs it for cell differentiation and also to develop neurons, a.k.a. the brain. So it’s important.

GRABER: Some scientists studied this question, and they found that both vegan and vegetarian women had worryingly low levels of vitamin B12. Although they don’t know if the levels were low enough to harm a developing fetus. Still, they said it’s best to play it safe—they think every pregnant vegetarian should take a supplement.

TWILLEY: So the claim that we’re trying to prove or disprove is that eating vegetarian is healthier. And even though it seemed pretty clear cut a few minutes ago, now it seems like it’s really not.

GRABER: For one thing, there’s nothing intrinsically healthier about a meat-free diet. Meat, dairy, and eggs have lots of things in them that are actually important to our health. And if you just replace them with junk food? That’s not going to make you healthier.

PHILLIPS: You can be a vegan and just eat potato chips and and drink wine. I mean, those would be kind of suitable for a vegan as well.

TWILLEY: That actually sounds like a perfect dinner. But anyway. The other thing is, obviously, you can include some meat and dairy and eggs in your diet and still eat lots and lots of whole grains and veggies and fruit. There’s no reason you couldn’t be consuming as much fiber and vitamins and antioxidants as a vegan.

GRABER: And then there’s the B12 thing. Nicolette Hahn Niman wrote a book called Defending Beef, and she thinks that animal products are part of a healthy diet.

NICOLETTE HAHN NIHMAN: So I actually strongly reject the argument that we should all be vegans, because I actually think if you’re eating a diet that requires you to take a manufactured supplement then there’s probably something wrong with your diet.

TWILLEY: That’s a position I sympathize with actually. But that’s if you’re a vegan. We’re looking at whether vegetarian diets are healthier, and you do at least get some vitamin B12 as a vegetarian who eats eggs and dairy.

GRABER: Even Corinna Koebnick—she’s the author of the study we just mentioned, the one that pointed out the potential harm of not getting enough B12 during pregnancy—she does not want to warn people off a vegetarian diet.

CORINNA KOEBNICK: The problem with doing a lot of studies on vegetarian diet and pointing out the risks is kind of distracting from the general issue we have that people have a very, very unhealthy diet. And I wish everybody would be as healthy as people are on a vegetarian diet.

TWILLEY: All this back and forth, and here we are: it’s not actually rocket science after all. You can eat healthily as an omnivore. You can eat healthily as a vegetarian. It’s not definitively proven by the research that one is healthier than the other, because it’s the overall balance in your individual diet that matters. That said, the science on this seems to show that a vegetarian diet is healthier than the average Western diet, for sure. That’s a pretty low bar, mind you.

GRABER: To quote Michael Pollan: “Eat food. Not too much. Mostly plants.” That seems to be the general consensus, and that’s where we’ve ended up here, too.

TWILLEY: So that’s the deal with not eating meat and your personal health. But what about the health of the planet?

(“LESS MEAT, LESS HEAT,” ARNOLD SCHWARZENEGGER)

GRABER: And that is our third and final claim: being a vegetarian is better for the planet. That’s pretty widely accepted as fact.

TWILLEY: I have absorbed it as the truth, for sure. But is it?

GRABER: This argument also goes way back in history. Back to one of Tristram’s favorite centuries, the 1700s. The environmental argument back then was that meat was not a great use of land.

STUART: Because it hogged, sorry for the pun, but it hogged the resources of earth to satisfy the appetite of a few at the expense of the many. And that argument, which emerged in the context of the utilitarian philosophy of the late 18th and early 19th century, came from the idea that we are obliged to create the greatest amount of good and happiness in the world, and, if that’s the case, then we should be feeding the greatest number of people and not wasting resources by feeding it to livestock and only feeding a few people with the meat and dairy.

TWILLEY: This argument emerged in Britain at this time for a couple of reasons. One, Britain is tiny. There is not a lot of land, full stop, so with population growth, how was everyone going to get fed? And then there’s another reason. The agricultural revolution, which started in England: that’s what made it possible to have big fields of crops, rather than little hand-tilled patches. So you could just grow a bunch of grains.

GRABER: Today, nearly three centuries later, that is still one of the main arguments in favor of vegetarianism. And it was one of the main points we heard from Gidon Eschel, too. He’s a professor of environmental physics and he wrote a paper that tried to figure out the environmental impact of beef versus pork versus chicken versus dairy and eggs versus a few main non-meat American crops such as potatoes.

ESCHEL: I mean, look. We have now 7.4 or so billion people on earth. Just in the U.S., there is a third of a billion right now. These population densities far exceed the carrying capacity really of the resources available.

TWILLEY: Gidon’s argument echoes those British utilitarians precisely. If you give up beef…

ESCHEL: The differences are staggering, just staggering. You know, you give up this tiny fraction of your diet per day, to reallocate the resources to something else, in this case soybeans, and you can sustain in full almost four individuals.

GRABER: Gidon’s argument isn’t just about land use, though. His paper also looks at the impact on water and pollution and greenhouse gas emissions of each of these different categories of meat and animal products.

ESCHEL: The most amazing thing is really the beef is in a firmament entirely of its own. Nothing comes close to beef. It is ten to fifty times more resource intensive than anything else. Plants by far are the most efficient. Then you have poultry, pork, eggs and dairy, to some extent, although there’s some subtlety there. And then in a completely different category, as distinct as the first class of the Queen Elizabeth II from swimming across the Atlantic, is beef.

TWILLEY: Gidon is not a lonely voice in the wilderness here. Other studies agree, particularly when it comes to climate change. We heard from Marco Springmann earlier, about the lives that could be saved by not eating meat. His study also looked at the greenhouse gas emissions that could be saved that way.

SPRINGMANN: We know that more than a quarter of all greenhouse gas emissions are due to the food system—in particular, due to livestock. For example, we know that in order to produce an equivalent amount of protein, beef emits about 250 times more than legumes. And, on a weight basis, beef emits about 20 times more than fruits and vegetables.

GRABER: Again, Marco projected out to 2050. He found that if everyone became vegan, global greenhouse gas emissions from food would be down 70 percent. A vegetarian diet would reduce them 60 percent. The point Marco’s making is a vegetarian diet can dramatically reduce greenhouse gas emissions.

TWILLEY: At least using the data that Marco was working with. And this is where it gets complicated.

GRABER: Nicolette—she wrote the book Defending Beef—she disagrees with the data Marco started with to get these figures. The large part of carbon emissions that make up this stat: that livestock are responsible for 25 percent of the global total? She says there are a lot of problems with that number.

TWILLEY: One of the flaws: a big chunk of that total livestock emissions number comes from deforestation in South America—basically, forests being cut down for either cattle grazing or to grow cattle feed. But that’s (a) a one time deal, and (b) to do with Brazilian laws around owning land, rather than actually being necessary to feed beef. So deforestation is a red herring, basically. It’s not inherent to livestock emissions.

GRABER: The other big part of global warming from beef— ou may have heard this—is methane.

TWILLEY: Cow farts.

GRABER: But Nicolette says that this, too, is not totally straightforward. Cows don’t necessarily fart as much as scientists think they do.

NIMAN: You know, what the cattle are eating, how they’re being managed on the pasture, how healthy the soils are, all these things are really important factors. None of that is ever taken into account in these methane totals. What they do is they take one animal, they put a—the poor creature—literally, they sort of drill into the side of the body, they put this bag on to their digestive tract, and they measure the methane that’s coming out of their digestive tract. And they say, okay, that’s how much a you know X animal of X size emits and therefore you’ve got to multiply that by the number of animals worldwide and that’s their methane contribution. Well, that’s absurd.

GRABER: It’s absurd because it totally depends on what the animals have been eating, it also depends on their gut microbes. It depends on how quickly the animals grow, which can vary dramatically in different ecosystems. The final total even depends on the methane-eating microbes in the local soil.

TWILLEY: So there are good arguments that that 25 percent of global emissions number that Marco was working with is wrong. It’s overstated.

GRABER: The other thing that Marco’s doing is using the model of conventional large-scale animal farms. On these farms, yes, methane comes from cow farts. But it also comes from manure lagoons, and those lagoons are a huge problem, both for global warming and local air quality. And then there’s runoff that pollutes local waterways, that’s also a big problem.

TWILLEY: But again, Nicolette’s point is: that’s not inherent. Beef doesn’t have to be raised that way.

NIMAN: If we de-industrialized the livestock industry, which is what I’m arguing for, a lot of those emissions just disappear.

GRABER: The kind of farm or ranch that Nicolette is advocating, these are often on the smaller side, farmers often have both plants and animals. Animals might help fertilize the field and eat some of the farm’s leftover products. Cows don’t have eat people food like grain, they’re eating grass. These aren’t big monocultures or huge sheds with tens of thousands of cows. These are the opposite of industrial agriculture.

TWILLEY: And so the response you sometimes hear at this point in the debate is that maybe Nicolette is right and well-managed livestock don’t have such a huge and terrible impact, but we can’t possible raise enough beef for us all on Nicolette’s kind of ranch. That’s Gidon’s response, anyway.

ESCHEL: It’s basically boutique farms, it’s not really serious food production. I mean, it’s plenty serious but it’s just not in scope very serious, okay? But can they feed the world? That’s the question. And the answer is, you know, is trivially no.

GRABER: And once again, Nicolette says not so fast.

NIMAN: There’s very good counter evidence on this. Other divisions of the food and agriculture organization, the United Nations, have put out a couple of reports about the importance—the actually essential nature of converting all agriculture to to sustainable and organic methods, and they say they say over and over again in different reports that they’ve put out that you can produce all the food that the world needs.

TWILLEY: I feel like I’m refereeing a prize fight here. Has Nicolette knocked Gidon and Marco out?

GRABER: Not quite yet. She’s got a few more punches to throw. Nicolette says there are some landscapes where it’s tough to grow plants all year but animals can grow pretty well.

NIMAN: And so if you’re, for example, let’s say living in the northeast in the middle of the winter, you know, it’s pretty much impossible to raise fruits and vegetables unless you’re raising them in a greenhouse and actually milk or meat might be by far the most environmentally appropriate food for that time of year in that location.

TWILLEY: Again, it’s all about the nuance and the complexity: if you live in Southern California, sure, be vegetarian. But it might not be the best environmental choice in other landscapes.

GRABER: And there’s one other kind of counter-intuitive point: cattle can actually be good for certain ecosystems.

TWILLEY: This is Nicolette’s killer right hook.

NIMAN: Literally just a few hundred years ago in the United States, we had, you know, around 100 million bison, which are huge grazing ruminants.

TWILLEY: So there were actually more bison on the land back then than there are adult cattle in the US today. And those bison were a crucial part of the grassland ecosystem.

GRABER: Nicolette is basing this part of her argument on the work of a guy named Alan Savory.

NIMAN: He argues that it’s the absence of these herds that is actually the Earth’s greatest problem today and that the domesticated animal, the domesticated cattle, rather than being a blight on the landscape, if it’s well managed, is one of the very few ways that we can hope to restore the ecosystem’s function the way they’re supposed to be.

TWILLEY: Alan Savory is an ecologist who started out his career dead-set against livestock. But, after years of research, he’s come 180. His studies have shown that properly managed livestock herds can actually have huge environmental benefits. Cattle can help soil sequester more carbon and retain more water and harbor more biodiversity.

GRABER: So you can have a meat system like the one we have today that’s really harmful to the environment, or you can have a meat system that maybe even helps the environment.

TWILLEY: And you can have a vegetarian diet that has to be grown in greenhouses or flown in and relies on irrigation and fertilizers, or a vegetarian diet that has a really small footprint. It’s completely context dependent.

STUART: And in some instances, for example, a waste-fed pig or a chicken, or indeed cow or sheep grazing on leaves and hillside grass that we can’t otherwise use, is to minimize our impact while satisfying our nutritional needs. And as long as we stick to the idea that the world can provide some meat and some dairy products but a hell of a lot less than the average per capita consumption is in Western Europe and America, I think we can balance our appetite, our moral philosophy, and our daily practice.

TWILLEY: Tristram wrote a whole book on vegetarianism. But he thinks that the v-word—that label is where this whole discussion about eating meat or not goes off the rails.

STUART: I’ll make no secret of the fact that I regard the creation of the word vegetarian and the creation of the Vegetarian Society in 1842 as the biggest strategic error that vegetarians made. Before that moment, the issue was one that many people engaged with, right? The moment you’ve created a name for yourselves and a society, vegetarians and vegetarianism, you created a pigeonhole that people can put you in and thereafter ignore, and that is indeed arguably what happened post-1842. It becomes a closed-off debate, only of interest to people on the inside of that particular pigeonhole. And pretty much boring for everyone else.

TWILLEY: And that is where we’re going wrong. These are not niche questions. These questions about morals and animal suffering and health and the environment—they’re questions that everyone should be thinking about, whether you include meat in your diet or not. And the vegetarian label—that doesn’t help open up that bigger conversation to more of us.

STUART: I think it is the creation of a polarizing identity that creates that challenge. It implies that I am on the side of the good and you are on side with the wrong. And that unsurprisingly puts people’s backs up. Mine too.

GRABER: But so to kind of round up the first questions we opened the show with—and I’m going to avoid that polarizing v-word—is not eating meat better morally, for your health, and for the environment? In today’s industrial food system, the answer is likely yes. It probably is. So if you want to give up meat for those reasons, go ahead.

TWILLEY: But our food system doesn’t have to be this way—and some people are creating a different system. They’re growing meat in a responsible way.

GRABER: And Nicolette says that if you buy some of that meat—again, overall, not as much meat as is in the average western diet—but if you do eat meat, as most of us still do, and if you buy that responsibly grown meat, what you’re actually doing is voting for those systems.

NIMAN: I never tell people who don’t eat meat that they should eat meat. But, if you’re already an omnivore, I think the really interesting ethical question is what can I do with my dollars that are going to support improvements in the food system in the direction that I want things to go in? I think every individual should be examining what they’re eating. Is it healthful? Was it raised in an ecologically sound way? Is it supporting the right kinds of farms, the kinds of farms that you want to be supporting? You know is it comporting with your values? And is it delicious?

(MUSIC)

TWILLEY: We are always on the side of deliciousness. That’s it for this episode.

(POST-ROLL)

TWILLEY: A huge thanks to our interviewees for this episode: JoAnn Davidson, listener Purvi Shah, Frankie Phillips, Nicolette Hahn Niman, Marco Springmann, Corinna Koebnick, Gidon Eschel, Tristram Stuart, and Colin Spencer. We have links to their books and articles on our website: you should definitely check them out. There’s so much good stuff we couldn’t squeeze in!

GRABER: Some of that good stuff will be going in our special email newsletter for sustaining supporters—anyone who gives $5 an episode or more through Patreon or on our website can look forward to getting lots of extra vegetarian goodies in their inbox next week, including the stories of two very famous vegetarians: Gandhi and … Hitler.

TWILLEY: And we’re back in a couple of weeks with an episode all about the weird world of wine.

GRABER: In case you were wondering, the celebrities making the vegetarian claims you heard were, in order, a young Natalie Portman, Moby, Alicia Silverstone, Ellen DeGeneres, Bill Clinton, and Arnold Schwarzenegger. Did you guess correctly? Til next time!