Nina Teicholz, the “nutritional Sherlock Holmes,” took nine years to craft her new book, The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet, and she recently spoke with Rootstock Radio host Theresa Marquez about what it took to create this enlightening account.

Before beginning this journey, Nina reviewed restaurants as a side-job. As she ate the “earthy, rich, textured, delicious” fat-laden dishes the chefs presented to her, she “magically lost this stubborn ten pounds I had been fighting, and the next time I went to my doctor, he said my cholesterol levels looked great.

“So it was a huge mystery how all these foods that we’ve been told all our lives are terrible for our health and somehow produced good health and a feeling of well-being in me. And that took nine years to unravel.”

The idea that fats—saturated fats, especially—were the cause of heart disease originated in the 1950s and was “based on almost no evidence—very weak, flawed evidence.”

Listen to the full interview above to learn more about the strange history of this long-standing dietary guideline and how the world is slowly coming to realize that fats are not the bad guys they was made out to be 50 years ago—and in fact, they can be quite good.

Transcript: Rootstock Radio Interview with Author Nina Teicholz

Welcome to Rootstock Radio. Join us as host Theresa Marquez talks to leaders from the Good Food movement about food, farming, and our global future. Rootstock Radio—propagating a healthy planet. Now, here’s host Theresa Marquez.

THERESA MARQUEZ: Welcome, friends. Today we are going to discuss one of my favorite topics: fat. I love fat, and I expect many of you do out there as well. I was very interested in a new book about fat that just came out, called The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet. It was written by an old acquaintance of mine, Nina Teicholz. I knew Nina when she worked for Gourmet magazine, and she also wrote for Men’s Health, The New Yorker, the Economist, and others. I recently found out that she also has a master’s in biology from Oxford University. So get ready to hear some controversial ideas as we discuss fat with Nina Teicholz.

And so, Nina, I was first of all just surprised, at first, that it was nine years in the making. I expect you didn’t think it would take that long. But I just wondered, while I was reading it, I felt like I was almost reading a detective novel. What did you find when you started it? Did you think it was going to be nine years? And did you have to learn lots of new things to even just write the book?

NINA TEICHOLZ: Yes. I mean—well first of all, thank you for having me. It’s just a pleasure to be here. And yes, of course I did not think it would take me so long. But the mystery that I started with was that, in addition to being an investigative reporter and working for NPR and writing for the Economist and New York Times and other places, I had this little side job reviewing restaurants for a throwaway paper in Manhattan. And we didn’t have the money to pay for meals, so I just had to eat whatever the chef decided to send out to me. At that time I was pretty much a vegetarian, but I discovered that what chefs want to send out to show off their skills is not stir-fry vegetables and chicken breasts but red meat, aged red meat, foie gras, creamy sauces, creamy cheeses.

And it was just a revelation—they were earthy, rich, textured, delicious. I found that I magically lost this stubborn ten pounds I had been fighting, and the next time I went to my doctor he said my cholesterol levels looked great. So that was a huge mystery how all these foods that we’ve been told all our lives are terrible for our health had somehow produced good health and a feeling of well-being in me.

And that took nine years to unravel, mainly because the science, nutritional science, there have been thousands upon thousands of studies in nutrition. Somebody called me the nutritional Sherlock Holmes, going back and digging up every single last study I could get my hands on to really try to get to the bottom of that paradox.

TM: And also, I was so amazed at how you didn’t take the science at face value—that you dug down in and said, really? Like for example, the Ancel Keys—gee, I don’t know how to feel about this man. I almost feel like that he single-handedly seemed to have been responsible for our low-fat diets.

NT: Yeah. So let me give your listeners a little sense of the history here, which is that the whole reason that we believe that saturated fats cause heart disease—saturated fats are the kind of fats found in meat, cheese, butter, dairy, eggs, also coconut oil—we believe they’re bad for health, and that goes back to the 1950s when the nation was in a panic over the rising tide of heart disease that had come pretty much out of nowhere in the early 1920s to be the nation’s number one killer. So President Eisenhower himself had a heart attack in 1955, was out of the Oval Office. And there was a sense of desperation about what to do, what was the answer.

And there were a number of ideas, but one man, this Ancel Keys, whom you mentioned, who was a pathologist at the University of Minnesota, he proposed that it was saturated fats that caused heart disease. They would raise your total cholesterol and clog your arteries and cause a heart attack. That was called his “diet-heart hypothesis.” It was an idea.

But he was this very outsized man, extremely charismatic. He had unshakable faith in his own beliefs. He was very aggressive and known as a bully even to his friends. And he managed to get that idea implanted into the American Heart Association. The first anti-saturated-fat dietary guidelines to prevent heart disease were published in 1961. In those days it was really just saturated fat—it wasn’t fat overall. Later on there grew to be a suspicion of all fats, but it really started with saturated fat. And that dietary guideline in 1961 was really like the acorn that grew into the giant oak tree of dietary advice that we have had for the last fifty years.

So it’s fair to say that Ancel Keys really set the whole ball rolling. Of course it’s a really complex story involving politics, personalities, biased bad science, and the industry influence. I mean, it’s a complex mesh of things that happened to keep this advice that allowed it to become institutionalized and to harden into the dogma that it’s become. But it did all start back then, based on almost no evidence—very weak, flawed evidence.

TM: I think that what he did was he became passionate about an idea that he really believed, and then he seemed to say, “Okay, I’m going to go after the material that supports that,” and ignores material that didn’t. And that seems very unscientific to me. How is it that those scientists who disagreed with him were silenced so easily?

NT: Well, you’re talking about two things there. One is this idea of selecting out the evidence that supports your beliefs and ignoring evidence that doesn’t. It’s a kind of bias that’s called “selection bias.” And we all do it. You know, in our lives, every day, all of us common people, we tend to gravitate toward things that support our beliefs that we already have. But in science, that’s why scientists are taught to be different. They’re taught to rigorously test their ideas and to try to reject them. That is the goal of science, because for every hundred ideas that somebody comes up with, maybe one might be right. So you’re taught to test and distrust all of your ideas in science.

But Ancel Keys, he believed, amazingly for science, that he should be right until proven wrong. That was what he said. And he had a number of like-minded colleagues who also came to believe that. And again, you have to understand, it’s in this context of the terrifying epidemic of heart disease felling men in their prime, and nutrition science was in its infancy, so nobody really understood what they were talking about. They just jumped the gun based on this weak science.

And then after the hypothesis, the diet-heart hypothesis became our institutional, official advice, then there became this process of every time data came along to the contrary, it had to be ignored. So a scientist named George Mann, for instance, went off to Kenya—he was from the University of Vanderbilt. He went off to Kenya, he discovered Masai warriors eating only meat, milk, and blood as their entire diet, 70 to 80 percent fat. He took electrocardiograms of four hundred of them and found hardly a trace of heart disease, any evidence of heart disease. He followed some to Nairobi [to] see what happened when they changed to a Western diet, and found that they looked a lot like the urban people, so it really wasn’t a genetic fluke. And he published that study in the most prominent journals of his day. And he was ridiculed, his study was ignored.

And just getting to this other point you mentioned of how critics were silenced: he, although he was a prominent scientist, eventually, because he was a critic, he was taken out one day by a secretary at the National Institute of Health, and she pulled him out into the hall, and she said, “Listen, Dr. Mann, if you keep up your opposition and your criticism of Ancel Keys it’s going to cost you your research grant.” And it did. That is not a singular story. I have a file full of stories like that.

So there was another, also well-known example by a Harvard-trained anthropologist named Stefansson who went off to the Canadian Arctic to live with the Inuit. For years he lived with them. He said they were the healthiest people he had ever seen. There was no trace of diabetes or obesity or heart disease. That was also checked up later by doctors who went to local hospitals also could not find any trace of that. But he found that their diet, they lived almost entirely on caribou and salmon, and occasionally in the summer months they would pick some berries. But they were pretty much the most, what did he call it, the most exquisitely carnivorous people he had ever met, with a diet of 70 to 80 percent fat. He wrote books about that. Nobody believed him.

He then came back and checked himself into Bellevue Hospital in New York City with a friend of his under a team of medical supervision, and for a year ate nothing but meat and fat, he and his friend. At the end of which they were in robust good health. Nothing could be found wrong with them. They had lost some weight. And also all those studies were ignored and sort of disregarded.

And another example, the most incredible example of selection bias, really, that I’ve ever seen was the biggest-ever test of Ancel Keys’s hypothesis, the idea that saturated fat is bad for health, was the Minnesota Coronary Survey on—forgive me if I get the numbers slightly wrong here—but about 8,000 men and women over four and a half years in a hospital setting. Some people had a diet of 18 percent saturated fat; others had a half of that, eating mainly margarine and other plant-based fats. At the end  of which there was a zero difference in heart disease rates or mortality.

And the leader of that study, a colleague of Ancel Keys, his name was Ivan Frantz, he did not publish those results for sixteen years, and when he did, he published them in a very obscure journal. And this was a NIH study, the biggest test of Ancel Keys’s hypothesis. And later when somebody asked him, “Well, why did you not publish those results which disproved Ancel Keys’s hypothesis?” And he said, “Well, we were just so disappointed in the way they turned out.”

TM: A couple of topics in the book that were the most disturbing to me, and the first one is about infants and children and withholding good fats from them. And the statistics that took a survey of moms and something like 80 percent of them, over 80 percent wanted to believe that they had to feed their children low-fat diets. That is disturbing to me, and I just wondered, how did we get there, where we’re now relating heart disease in fifty- and sixty-year-old men to taking fat away…? And is there anything, follow-up studies, trying to show that that’s not good for children?

NT: Yeah, it’s very sad, what happened to women and children in this story. Ancel Keys’s work on all men in 1961, when the first dietary guidelines, when those first guidelines were issued, all the data was only on men. When the USDA got into the picture, just the whole government getting into the picture and recommending this diet for women and all children over the age of two, zero data on women and children still. And there was no data on women and children until the late 1990s—they didn’t do any trials on women or children.

And some of the earlier indications had been worrying. For instance, when they looked at heart disease risk factors, cholesterol, they found out for women, women didn’t look at all like men because women have, you know, hormonal differences, and the higher cholesterol that you had as a woman was associated with longer life. But how many women go to the doctor and have them feel like, “Oh, good job, your cholesterol is high!”

TM: (laughing) I don’t think so!

NT: But children—so getting back to children, they started to be studied, but they were lumped in, women and children were lumped in with middle-age men, just assuming that you could never start, it was never too early to start off the fight against heart disease. And there was also kind of this practical point that the whole family sits down to dinner together. So it was just sort of assumed that what was going to work for the middle-age men should also work for the women and the children, even though children have different nutritional needs as they’re growing. I mean, that’s just so obvious.

But when they finally studied children on a low-fat diet, there were a number of really small trials—not many children, most of them quite young. None of them followed the children into adolescence or adulthood to see if they were going to successfully reproduce or… They found that children suffered nutritional deficiencies on that diet, so all kinds of minerals and vitamins that they just couldn’t get adequately without supplements.

And there were a number of pediatricians—actually the pediatricians were a group that really held out against Ancel Keys and his colleagues. The longest holdouts were the pediatricians who said, “What right do you have to say that the diet for the aging octogenarian is what I should be feeding a young child, a young growing child?” But by the 1990s, the American Academy of Pediatrics, along with every other health group, had pretty much, they had been under so much pressure to follow the general dietary guidelines, which then it was not just the American Heart Association but the USDA and the National Institute of Health. There was so much pressure to get on board with the diet-heart hypothesis that they did too.

And when I spoke to pediatricians about it, they said, well, it just became the default diet. And so then again you had to prove that it wasn’t the best diet for children—but it had never been proven that it was even a good diet for children.

TM: When I grew up in the 1950s and 1960s, there was no one obese around us. And that was like in the 1950s. So something, I keep telling people, I don’t believe this about whole milk—I just refuse to believe this. And now I have really good science or information that proves that I was right.

NT: Yeah, the obesity epidemic began in 1980, which is when the U.S. government first published its low-fat dietary guidelines. That’s when the obesity epidemic began. It doesn’t mean… Americans started eating low-fat in the 1960s and 1970s, but then when the government got behind it, it was sort of in earnest. But you’re right—I mean, skim milk didn’t exist until, I think, the 1970s. There was no skim milk. And one of the reasons that the message of my book, the arguments for why meat, cheese, butter, dairy, eggs are not bad for health, is that there are still people who remember their grandparents eating meat, eating cheese. They remember their long-lived grandparents, they remember their cultural heritage.

And one of the things that’s true in the United States is that because we’re a nation of immigrants, we’re so divorced from our culture and our past, our food heritage. And many women in the 1950s just got all their food ideas from food magazines, kind of erased our cultural heritage. But there are still people who remember, “Oh, yeah, I used to spread—”

TM: Yeah, we old folks!

NT: Me too! But I hear so many people say, “Oh yeah, we used to spread schmaltz”—you know, chicken fat—“on toast. And my grandmother, gee, she lived to ninety-five.” You know, these stories are—people remember, there’s a kind of commonsense memory.

TM: It really, really bothers me that it’s actually legislated that we can’t have whole milk in public schools, across the whole country.

NT: Well, one, just to open a parentheses for a second and talk about why whole milk is so important. The fat in milk is what enables you to absorb the vitamins. So vitamins A and D can only be absorbed if you have the fat that comes with it in milk. If you have skim milk, you can’t absorb the vitamins. And without vitamins A and D, you can’t absorb the minerals in milk. So you aren’t getting the good stuff in milk unless you have the fat that naturally comes with it.

Fat also fills you up and satiates you, so it actually makes you full. That’s what prevents people from overeating. One of the theories about why people overeat now is that we’re not getting enough fat in our diet. Fat and protein is what’s naturally satiating in your diet. And also, without the fat, the calcium in milk turns into insoluble calcium soaps in your intestine instead. So it’s just—and skim milk is higher in carbohydrates, higher in sugars than regular whole-fat milk. So whole-fat milk is so much clearly better nutritionally.

I keep trying to drop the hint in every interview that I do: we need to start the Parents for Whole Milk movement.

TM: All right! I’m there! I’ll start it.

NT: But ultimately, the school lunch program, what they buy and don’t buy—it’s also true for the Women, Infants, and Children (WIC) program—it all flows from the USDA dietary guidelines. That is the most powerful report in the world, because those diet guidelines not only dictate everything that’s done in this country but also they’ve been exported to the whole world. They are an extremely anti-saturated-fat group of scientists, pushing the limits on saturated fat ever lower. And, speaking again of selection bias, there have actually been two really important large meta-analyses done on all the available evidence looking at saturated fat. And both independent analyses, including scientists from Harvard and Cambridge and the University of Berkeley, those have both concluded that saturated fats cannot be said to cause heart disease. They do not cause heart disease.

And the reason that we haven’t been eating meat, cheese, butter, dairy, eggs is due to their saturated fat content. But the scientists on the USDA dietary committee, that expert panel, will not reckon with that science and have not. And so really, it is an important moment right now to write your congressmen and tell them that the dietary guideline expert panel is stacked with low-fat people, that they’re not addressing the science, that they have excluded any scientist with views other than low fat. And I think it’s ultimately the senate could intervene and force the committee to become more balanced, because it’s truly an extremist group of people. They have been talking about reducing the allowable amount of saturated fat to 5 to 6 percent of total calories, which is really undocumented in human history, below what you can see in any human population in the world, except in periods of extreme privation and postwar periods. So it’s a dire situation right now.

But I think that one of the arguments that I think would make Congress and any commonsense person respond is that, you know, the crushing load of chronic disease that we now suffer, and diabetes and obesity, and we still have heart disease the number one killer, and yet Americans over the last thirty years have pretty much complied with the dietary guidelines. You know, we’ve cut our saturated fat by 11 percent in the last thirty years; we’ve increased our carbohydrates by 25 percent, and we’ve increased fruits and vegetables by 17 percent. We have done what we’ve been told. And we look awful.

TM: There’s a couple of things I’m wondering about. One is, can we trust our cravings even, anymore? I’m thinking about when I was little, I used to crave chicken skin. When my mother would make fried chicken, I could eat all the skin off the chicken, and it just made me so happy. Of course, she wouldn’t let me, but that’s what I would have—

NT: But you should have.

TM: And it was always the fattier parts of the chicken or meat I was drawn to. And I always wondered about, wow, why did I have those cravings at that young age? And then the other thing that kind of bothers me with regards to the whole commonsense, first getting in touch with can we trust our cravings, can we trust our own feelings about…how do we get in touch with our bodies now, and are we in touch with them. But then the second thing is that, wow, can we trust what the scientists or the nutritionists say that we should do?

NT: I want to just start with this question of trusting your body and tie it in to what we were saying earlier about fat and protein being uniquely satiating, right? So you’re not hungry on them. Everybody knows what hunger is, right? That’s something where you can trust your body if you’re hungry. And a high-fat diet, a diet that’s high in fat and low in carbohydrates—so you know, as a shorthand I could just say the Atkins diet. That diet is successful at weight loss without hunger. You’re allowed to eat as much of that high-fat food as you want. And you can trust, you can follow your cravings for chicken skin, for drinking the droppings from the pan, or whatever you want, or bacon.

You know, Atkins was kind of a pariah in his day, and he only had his medical files to point to in the early 1970s; they were only anecdotal. But over the last decade there have been dozens of clinical trials on his diet, really, and they have unequivocally shown that his diet is better, not only for weight loss but also for fighting heart disease and diabetes. So you know, for a long time there was this suspicion that you would gain a waistline on his diet but you would pay for it with a heart attack down the line. That turns out not to be true. And these are clinical trials of two years, so you really get to see the long-term effects. And those have really put to rest any health concerns about that diet and have shown it in fact to be the healthiest.

You know, can you trust nutrition scientists? Well, I think we’re in a bad way with nutrition science now because it really has been half a century of believing this dietary dogma that turns out not to have solid science behind it. But it has become institutionalized. It is the set of nutrition principles that is taught in… Every nutritionist, every medical doctor, every classroom curricula, they are all taught that restricting fat, saturated fat, is the best thing that you can possibly do for your health. And it’s going to be a while before that changes. There is a small group, and growing group, of scientists who have challenged that, but you know, it’s not mainstream.

TM: Well, I would hate to end this interview without at least asking you about sugar, which I kind of read that Ancel Keys, when asked about sugar, just basically pushed it aside. But do you—and of course, I’m sure that you came across sugar in the research, some. Do you think that the sugar, the amount of increase of consumption of sugar, I’m assuming, that we get both from regular sugar, from high-fructose corn syrup, might have something to do with some of the health problems that we have, like obesity, et cetera?

NT: Yeah. Well, I think the best science now… Again, this decade, last decade of clinical trials really does show that carbohydrates generally—so too many carbohydrates, grain, pasta, bread, and also sugar is in that grab bag, but they looked at just carbohydrates generally—too many of those leads to worsened heart disease risk factors and obesity and problems that lead to diabetes, so your diabetes markers.

Can we single out sugar for particular blame? I think we don’t really have much clinical trial evidence particularly on sugar. But it is true that in populations where they, when sugar is introduced, that’s when you tend to see the first cases of heart disease. In the late 1700s in England, they had just been getting sugar from the sugar colonies, and their first case of heart disease was in 1768. And that was true also in France, the first cases of heart disease.

And it was a competing theory to Ancel Keys’s theory, the idea that it was sugar. It was particularly, there was a British, a guy named John Yudkin at Kings College in London, who was, sort of offered this competing hypothesis to Ancel Keys’s idea. And Keys was absolutely relentlessly vicious towards Yudkin and sort of squashed this alternative—basically squashed his competitor. But yes, I think that…

So that idea has been out there, and it’s recently been revived. There’s the Fed Up movie by Katie Couric and talking about the problems of sugar. You know, reducing sugar in our diet can do nothing but good. But again, it may just be that if we eat 60 percent of all of our calories as carbohydrates, even if they’re the supposedly good whole-grain kind, that just too many carbohydrates overall, as we’ve been told to eat by the government, is just not a healthy amount of carbohydrates in the diet.

TM: Listen, when you charge the Hill with the dietary guidelines, would you mind calling me up? And you moms out there, it looks like we might all have to get together and form this moms group to charge the Hill.

NT: I want Mothers for Whole Milk. That’s what I want up there.

TM: I’m with you. So maybe together we’ll get this started and get whole milk back in the public schools and in our diets.

NT: That would be a huge contribution, just that.

TM: Thank you so much. It’s been really, really fun.

NT: Thank you for having me.

TM: I want to thank Nina Teicholz for being our guest today. Pick up the book The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet. It’s a fascinating story and a great book. It’s very, very accessible reading. Thank you all for being with us.

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