The Limitations of Occam’s Razor in Biological Science

Gary Taubes’ work changed my life and set me on a journey of reading nutrition and health research as well as eating and exercising differently. However, Taubes himself says that he “fell through the looking glass” when he discovered research on carbohydrates and weight loss that he asserts was ignored by the mainstream. Given the recommendations of the American Heart Assoc, American Diabetes Assoc, etc, it appears he was right.

But I do think that Gary has remained focused on the low-carb meme for too long and it is time for him to move on. I think his physics background has tempted him to want to reduce the problem of obesity to single, basic cause, as one would do in hard sciences. Gary refers to Occam’s razor in this regard in his book Good Calories Bad Calories – that “other things being equal, a simpler explanation is better than a more complex one.”  When I first read GCBC, I thought this was a very useful approach, but now, having read more widely in the field of alternative health and diet, I have begun to see that biological systems are very complex and adaptable, and that more than one approach can lead to the same result. Indeed, there are probably elite athletes who are vegetarians, vegans, omnivores, paleo followers, low-carbers,  etc. And they all perform at extraordinary levels. On paper, maybe one or two of these diets are better, but in practice, individuals need to determine what’s best for them.  Perhaps the simplest explanation is still preferable, but it seems clear than there is no single path to optimal health / weight loss. Arriving at your destination takes each person along a different route, in a way similar to that of creative journeys or endeavours.

Now it is time for Gary Taubes to change his direction away from his reductive view that carbohydrate restriction is the only truly effective path to weight loss and optimal health. He is one of the most interesting and intelligent health writers working today, and I would like to see him come back through the looking glass and apply his formidable research, writing and discernment skills to other aspects of the problem of health.

Interview with Gary Taubes – Part Three

JD: Here is a quote from an article you wrote for Discover Magazine in 1997:

“There is a theory that creativity arises when individuals are out of sync with their environment. To put it simply, people who fit in with their communities have insufficient motivation to risk their psyches in creating something truly new, while those who are out of sync are driven by the constant need to prove their worth.” -Beyond the Soapsuds Universe, Discover Magazine

How well does your description of how creativity arises describe you?

GT: It’s an interesting question. That idea comes from a theory by Mihaly Csikszentmihalyi, who wrote a book called Flow: the Psychology of Optimal Experience. You do need someone to come in from outside. One of the theories about why mathematicians do their best work when they’re young is because they’re not yet educated enough to know what seems obviously wrong . So they try new things.

I was thinking today about why crazy people seem to be so creative – is it because they’re not bound to the social structures and mores that the rest of us have lived with? They think outside of the box, and usually 99% of the time it doesn’t work, and they create crap, but the 1% – somebody who is completely disconnected from the way the rest of us think – creates something that resonates and we think that person is a creative genius. Picasso could have been seen as a nutcase, but instead there was something about cubism that resonated and we all say this guy’s a genius. But he’s obviously different. He’s built differently from other people. Picasso is probably one of the examples that was used by Csikszentmihalyi when he was developing his theory.

When Gina Kolata reviewed my book, Good Calories, Bad Calories in the New York Times, she said I was a brave and bold science writer. I guess she meant that I’m brave because I’m putting myself out there. One advantage I have is I don’t have to worry about getting funding from the nutrition community. So being an outsider in that sense works. Another advantage is that I don’t have to spend all my time reading the journals to keep up with what other people are doing because I’m not competing with them. I can spend my time reading the history.

I definitely think differently from the nutritionists in general, because I was trained by very good experimental scientists in the physics community, when I spent all my time writing about high energy physics and cold fusion. These people were teaching me about how they think. When they were telling me what they thought was wrong with experiments, I was seeing how they think about science. So there were a lot of advantages I had there.

But still, I just stumbled into this. I could have spent my whole life being a kind of science journalism equivalent of Philip Marlowe the detective, and gotten these little cases that were interesting. Something where I could kind of get my hands dirty and do some investigations that other science journalists didn’t have the time or the energy or the desire to do. And then I just sort of fell through the looking glass, and suddenly I was in this world where all the science is terrible and there is actually a legitimate hypothesis that you could see had been left behind, that tended the answer all these questions and explain the observations.

I’m also an obsessive researcher. I have a personality that always thinks about what it doesn’t know. Like rich people who don’t care about what they have, but only care about what they haven’t bought yet. It’s a kind of psychological problem. It bugs me when somebody finds something in this field that I don’t know about. Like a paper that I didn’t read that’s important and so I keep looking and I keep reading the literature. There are always things you don’t know. And it just keeps leading you from one path to another.

The other thing is I hate writing – it doesn’t come easy to me. So the research is always a great way to procrastinate. You just keep researching, which is fun.

Most of us don’t have the talent to actually analyze what’s being said. You never know what people are leaving out. Which is something that Gina Kolata said correctly about my book – you don’t know what I’m leaving out. Then somebody comes along and says “oh look at this, he left this out.” Good Calories, Bad Calories is a 500 page book written about 150 years of science – there is an enormous amount left out. There are a lot of decisions being made along the way.

Actually, it’s funny, the original draft of the book was 200,000 words longer and unfinished. I gave it to my editor. I said “I can’t write anymore.” I know it’s 200, 000 words longer than it should be and I’m not done. I was saying in the book “here is the history, here is what happened, here is the data, here is how it was interpreted incorrectly, here is how the establishment took it, and here is how it is wrong. Here is the correct interpretation, and here is how that has been refuted.”

The editor said that I don’t have to give everybody else’s opinion. He said that if I lecture on it, people could ask questions, and then I can explain. That got rid of 180,000 words right there. Then of course what happens is people say what about this, what about that. Taubes cherry-picks because he doesn’t include those things. The same people, like Gina Kolata, who accuse me of going on and on and on and on, will then say but he leaves this out, he leaves that out. And that’s when I really want to pull my hair out.

JD: Tell me three things that you have learned from science about health that you are certain of.

GT: I’m not really sure of anything. I’ll tell you a funny story. A friend of the family is science director of Phoenix House, which are rehab centres all around America. They’re a pretty big deal in New York City. He took Why We Get Fat on vacation with him about five weeks ago and I got an email from him saying that he just found it fantastic. Then I got a call from him about a week ago. He got off the plane after he read the book and hadn’t had any carbs since. Lost 17 lbs in five weeks. He total cholesterol is 140, his blood pressure was 110 over 70, he’s off statins and beta blockers. And all I could think was thank god it didn’t kill him.

JD: So the answer to the question is nothing, right?

GT: Yeah, I’d still worry. I know – and this isn’t science, it’s personal experience – that I can eat as much as I want now. Without the carbohydrates it has no effect on my weight. Is it going to kill me? That I’m not so positive about. But I know that my weight is regulated by the carbohydrates that I consume. The research tells it to me, the science seems clear, but it’s my personal experience indeed that makes me know it for sure.

Interview with Gary Taubes, Part Two

For Part One of this interview, see the previous post.

JD: It’s like somebody ran a restaurant for 20 or 30 years and they never had a health inspection. Then suddenly one day a health inspector walked in and went “Oh my god, what a mess!” And the people who have been there all along, they can’t see it because they’re so used to it, and they say “What are you talking about?”

GT: Yes, that’s a very good metaphor. This calories idea is a classic. I believed the calories-in, calories-out idea until about 2004, I’d say, and the more I talk about it, the less I can believe that anyone else really believes it. The idea that the accumulation of fat in the human body would be regulated by merely how much we ate and exercised and nothing else is just absurd.

It’s funny, one of the criticisms of my sugar story in New York Times Magazine was from my old friend Ellen Shell, who can’t get over the fact that I keep concluding things about nutrition that are the opposite of the things she’s concluded over the years. This has indeed ruined our friendship.

She said it was preposterous that the nutrients in the diet would have a differential effect on weight control. I would say if the nutrients in the diet have a differential effect on the hormones that regulate weight, it would be preposterous to say that they didn’t. And when I lecture about it, I use the analogy of a crowded restaurant to explain the problem with this belief that we get fat because we eat too much; because we take in more calories that we expend.

When you’re too fat, you’ve got too much energy in your fat tissue. When a restaurant is very crowded, there is a lot of energy in the people there. So you ask why is there so much energy in the form of people in the restaurant? If I said to you well, it’s so crowded because more people came in that left, you’d assume I was being a wise-ass, right? Because of course more people came in that left. It’s the logical equivalent to saying you get fat because you take in more calories that you expend. If more people come in than leave, then the restaurant has to get more crowded. It has to be true. But it still tells you absolutely nothing about why the restaurant’s crowded. Why did you eat more, and why did you get fatter? Why did more people walk into the restaurant and why that restaurant rather than the one next door which isn’t crowded?

JD: Because it has a really good band.

GT: The restaurant might have a good band, and maybe Angelina Jolie is eating there. Who knows, maybe the food is good and it’s happy hour in that restaurant. They’re having a party. There are a lot of reasons why it might be crowded and the other restaurants aren’t. And they all have to do with characteristics either inside the restaurant or outside – maybe it’s crowded because it started to rain and everyone ran in. But that more people entered than left tells you nothing. And yet that’s what we’ve been saying about obesity for 50 years.

Here is the difference in the metaphor. To say you get fat because you eat too much is like saying that the restaurant got crowded because more people came into Ottawa than left. The fat cell got fat because more fat entered the body than left. So how did the people who entered Ottawa and didn’t leave, get into the restaurant? Ottawa could get more crowded and the restaurant stays empty because they’re going to a football game or something.

JD: So, you take in energy in the form of food, but the energy could go elsewhere rather than going into the fat cell. It could be expended.

GT: Why does it go into the fat cell?

JD: A central criticism of your work in Good Calories, Bad Calories and Why We Get Fat is that you focus on one element of the diet as being responsible for metabolic syndrome. This has, of course, happened before. Over the years, we’ve been told not to eat fat, especially saturated fat, red meat, white bread, salt, sugar, eggs, etc. Here is a quote from Barry Glassner that speaks very well to this problem or argument:

My own view is eat and let eat. I’m perfectly comfortable with people following an Atkins diet and eating meat with every meal, or a vegan diet and never eating any animal products. What I’m uncomfortable with are the exaggerated claims that they make, that a meatless regimen can prevent most every serious malady from heart disease to world hunger, or that following an Atkins diet is a magical potion for longevity and weight loss.

I think there are millions and millions of Americans who try to follow one version or another of the “gospel of naught,” which is this notion that the worth of a meal lies primarily in what it lacks rather than what it has. So the less sugar, salt, fat, calories, preservatives, animal products, carbs, additives or whatever the person is concerned about, the better the food. And this seems to me a quite curious notion that’s worth a lot more attention than we’ve given it.” – Barry Glassner, The Gospel of Food

Yet you’re saying that there really is something to worry about, and you arrived at this conclusion by following the science. How to you respond to this criticism?  Glassner wants to defuse the anxiety about food that we experience inNorth America.

GT: One of the reasons I went into this field is because I wanted to as well. I was so offended by the idea that the food police kept me from eating avocados and peanut butter for like a decade because they have dietary fat in them. And then the science is terrible.

But the fact that we were wrong about fat or we were wrong about meat doesn’t mean de facto we were wrong sugar or refined carbs being the cause of nutritional diseases like diabetes.

The argument I’m making is that the science of nutrition has been terrible. There is a lot of evidence suggesting the western diet is bad. There’s some factor of the western diet that causes heart disease, diabetes, obesity, cancer and probably Alzheimer’s as well. There used to be populations that didn’t eat the western diet and didn’t have these diseases. And there are variations in cancer rates between nations and between populations. When populations migrate from one area to another, cancer rates tend to change, so you can make the assumption that something is causing cancer. Different types of cancer might have different causes. The classic example – breast cancer is almost non-existent in Japanese women living in Japan. They come to the US and by the second generation the rates of breast cancer are the same as any other ethnic group here. Either they’re protected from it in Japan or something is causing it here.

Now Barry doesn’t have to worry about breast cancer. But if you get breast cancer, which one in nine American women do, you might be more concerned about what it was that caused it, because something does. There is a significant amount of evidence that the diseases of civilization argument is right. Then the question is, what is it about western diets and lifestyle? The vegetarians say it’s meat, the physical activity proponents say it’s sedentary behaviour, and a lot of people will say sugar and energy-dense foods and obesity, because obesity associates with all these diseases.

So then it’s just eating too much food in general. I’m making the argument that there is a lot of evidence implicating refined carbs and sugar. I know that it’s uncomfortable to contemplate this, but if you look at the evidence, if you read Good Calories, Bad Calories, I don’t see how you could come away not thinking that this is a very viable hypothesis. And then what you want to know is can it be refuted. What experiments do you have to do to refute it?

Recently I lectured at the Tufts University nutrition department and Alice Lichtenstein, is a professor emeritus there. However many US dietary guideline committees there have been, she’s been on them. When I was done with the lecture, which was the one debunking the calories myth and replacing it with the carbohydrates and insulin hypothesis, Alice basically stood up and explained why everything I said was wrong.

Instead of considering the whole of the argument and deciding to test it, she had an explanation for everything. What I would want after giving a presentation like this, is to have the audience say “have you considered this,” “have you considered that,” and how would you test it, because it’s a viable hypothesis.

And then on top of it, you have these clinical trials showing that if you remove the carbohydrates from the diet – the Atkins diet is basically the diet that removes the carbohydrates – but keep calories high, the subjects in the trial lose weight and their heart disease risk factors get better. If they’re diabetic, their diabetes gets better, their metabolic syndrome goes away.  There is a consistent story that can be told from the late 19th century through the latest science today. So that’s my argument against Barry’s ideas. It sounds good, what he’s saying, eat what you want, but if you called him you know, he would probably tell you that he’s on statins and beta blockers.

When you’re an authority, you have to assert your authority. So if you’re a nutrition writer or you run an obesity clinic and you’ve been saying one thing your whole life, it’s supposed to be right. If somebody else comes along and says something different, even if you agree with it, you still have to somehow convince your readers and yourself that you’re a smart person and that you know something that person doesn’t. If it’s drastically different from your own approach, then you can’t allow it to stand.

JD: Dr. Jay Wortman is celebrated for his work using a low carb diet to help an Aboriginal community in BC. People seem to assume that such a diet is acceptable for Native people because they are somehow more “paleolithic” than the rest of us. It is rare to hear criticism of the low carb diet when Jay Wortman is using it to help First Nations people. Yet when it comes applying it to non-Native people, there is a great deal more criticism. What do you think of that? Why is the low carbohydrate diet considered an innovative approach to obesity in the one case, and a potentially dangerous fad diet when recommended to a broader population?

GT: It’s an interesting way of looking at it. In the U.S., we don’t have the kind of Inuit and First Nations presence the way you do. Native Americans are not as much a part of our psyche. So there is no population that is encouraged to follow that kind of diet. I’ll show you how twisted this world is: if you read the American Institute of Cancer Research World Cancer Fund Report on diet, physical activity and cancer, they talk about the paleolithic diet, which is a diet where we basically eat what we evolved to eat, and they refer to the paleolithic peoples as gather-hunters instead of hunter-gatherers.

JD: Because they want to put the emphasis on the fruits and vegetables.

GT: Yeah. What world do we live in?

JD: Whatever world we want to, I guess.

GT: Yeah, I guess that’s the answer. I mean, even if they’re right, why change the name?

JD: Well, the Inuit have never been gatherer-hunters, that’s for sure.

GT: Back in the 1980s there was a study done on a population in Africa – the ones with the exclamation point at the beginning – I never know how to pronounce it. The book that came out of it was called Man the Hunter. Its publication sparked a feminist response trying to make the point that most of the food in these populations was gathered by the women, so it should have been called Woman the Gatherer instead of Man the Hunter. But we’re talking human health here, not feminism. It’s theoretically a science. When I really want to piss people off when I lecture, I say “let’s just pretend this is a science.” What would we do if this were really science – how would we interpret this data?

JD: I kind of wonder if people approve of the diet when it comes to First Nations is because they are seen as more paleolithic. Then, you know, there is kind of an undercurrent of racism.

GT: Even here I think – people who never do the Atkins diet would will do a paleo diet. They see the Atkins diet as some weird fad diet where you’re eating quarter pound cheese burgers or something. There is so much baggage. I’ve had doctors come up to me after lectures and say, of course I agree with everything you say, and of course I would never prescribe the Atkins diet.

Rob Lustig, who is the main character in my sugar story – even he thinks that the Atkins diet is some kind of weird fad. He was brought up in this medical community that’s inculcated with the belief that you can tell people not to eat sugar, but you still don’t go so far as to tell them that fat can be good for you and that you should, or could eat it.

One of the things I was trained to do when I was writing about high energy physics and talking to all these very good experimental physicists, is to be willing to break things down and throw them out if they don’t work.

Lustig’s done some pretty good work, but it doesn’t involve tearing down what other people believe, or tearing down conventional wisdom. You just sort of add onto it or go sideways from it.

You’ve got to start again, get rid of all the detritus of calories and fat being bad and look at what the data really show you. And not many people think that way. When they’re looking at these diets, people have this notion that they could eat fat and they could eat meat and that it won’t kill them. Because how can it not be true?

JD: It seems that what you’re trying to do is get past being tricked by your subjectivity. People get tricked by their own experiences. You mentioned in one of your interviews about how Mehmet Oz is very thin, sort of waif-like person who probably can’t conceive of carbohydrates as being something that doesn’t give you energy. Glenn Gaesser who wrote The Spark – he recommends that people eat a huge amount of carbohydrates. I knew without even trying it that that diet would make me hungry all the time. I think maybe because he’s such a thin person, for him, it makes sense, on a biological level. It’s the truth for him, so that he can’t see past it. Is that what you mean when you say you’re obsessed with getting to the truth?

GT: Yes, one of the things you have to do is distance yourself from subjective perceptions. In my case – I’m not naturally lean. I mean, I’m built like a linebacker. I could probably weigh 260 or 270 if I let myself. My brother, on the other hand, is naturally lean and always has been, so we have entirely different beliefs about food. The research scientists are a little different, but a lot of the people who get into nutrition are people who are lean and healthy and want to spread the word – what they know to be true. They’re different from the people who have problems with weight.

Certainly exercise physiology is full of lean muscular athletes. It’s like having a track star try to train a sumo wrestler. It doesn’t make any sense. There’s a fellow here in Berkeley, he’s about 5”8, maybe 140 pounds. When I interviewed him for Good Calories, Bad Calories, he was telling me that when he was in med school at Yale he used to run ten miles every day. He believes that if every fat person just ran ten miles a night like he did they’d be thin too. This is a very smart metabolism researcher. But he cannot get past the idea that he isn’t thin because he ran ten miles a day. He ran ten miles a day because he was thin. That’s what his body wanted to do with the food it consumed.

These issues of causality are really fascinating. The gestalt paradigm has been so overused that it’s kind of an embarrassment to evoke it. But if you read Thomas Kuhn, the metaphor he uses are these optical illusions – these drawings, like the naked woman on the face of Freud, called “What’s on the mind of a man.” You screw up your eyes one way, and you see a naked woman. You screw up your eyes the other way, and you suddenly see Freud – you can’t see the naked woman anymore. And if you screw up your head again then you just see the naked woman and you can’t see Freud anymore. That was the metaphor that Kuhn used for paradigms and it’s really true. Once you see the causality going the other way, you can’t understand how anyone could seriously believe the opposite. The metabolism researcher I referred to above seriously believes that his body has been shaped by these ten mile runs.

My goal in life is to somehow get people to switch their way of looking at it. When I give lectures I feel like I accomplish it for about 36 hours. After the lecture the shifting of paradigms has about a 36 hour half life and then instead of the naked woman suddenly you see Freud and that’s all you see, and you don’t remember how you ever saw the naked woman.

It’s one of the fundamental problems in all of medicine. Because I am something or I do something, I believe that everyone can be like me. Years ago I wrote about the controversy on the use of mammograms for women in their forties. Basically there was no benefit. So why did mammographers believe so much in the effectiveness of mammograms for this age group?

A woman comes in and you scan her and you find a tumour. You take it out and you believe you saved her life. A woman comes in, has a mammogram, you find a tumour, you take it out and she dies anyway. You believe she didn’t come in soon enough. A woman doesn’t come in, has a tumour and dies; you think she should have gotten the mammogram. You would have saved her life, right? The woman, who had the mammogram followed by surgery and lived, might have lived anyway. All these logical fallacies that we perpetuate. It’s extremely difficult to step outside of that.

As Francis Bacon said four hundred years ago, we are incapable of seeing the world as it is. There are all these distortions that our brains inflict on our perception. So what we have to do is figure out a way to get rid of these distortions so we can see things they way they really are. That was the scientific method. Bacon’s book was called Novo Organum, which means a new technology. It was a new technology of reasoning to try and get around these fallacies, these errors that are unavoidable because we’re human.

I had an argument with one of my best friends in science journalism, David Friedman, who wrote the cover story for Scientific American in February on obesity arguing that the only way we’re going to stop the obesity epidemic is with behavioural therapy. I felt like I was reading an article from the early 1970s. He’s read my book. We’ve talked about it. He said to me in an email, “not even you really believe that it’s not about calories.” We’re living in different paradigms.

The idea that sugar is bad for you has been around for a long time. The essence of what I’m arguing, and that Robert Lustig is saying, is that it’s not about calories. It’s about the metabolic and hormonal effects of refined carbohydrates and sugar. The medical community will get it. I mean, they’ve gone beyond such simple things as hormones. Now it’s all about proteomics and transduction pathways and stuff, but they will get it.

I recently wrote a story on sugar for the New York Times Magazine story called “Is Sugar Toxic.” The cancer aspect of my sugar story had been researched first for a piece I’m doing for Science on cancer that I haven’t had time to write yet. As part of that research, I interviewed Craig Thompson, a cancer researcher who is now president of Memorial Sloan Kettering Cancer Center and Lewis Cantley, a cancer researcher at Harvard.

In my article I explain how both of these researchers think it’s likely that sugar is the dietary cause of many cancers. If sugar causes insulin resistance, they say, then the conclusion is hard to avoid that sugar causes some cancers, at least. For just this reason, neither of these men will eat sugar or high-fructose corn syrup, if they can avoid it. Cantley put it this way: “Sugar scares me.”

Thompson knew nothing of my work, but he had come to the same conclusions because they were obvious to him. He didn’t train in nutrition and obesity – he trained in cancer research. He’s currently studying how cells determine if they’re going to stay alive or not. One of the points he makes is that every cell has more than enough nutrients surrounding it to survive. The question is what makes a cell decide to take up more nutrients. So the idea of overeating is meaningless, because the cells could always overeat. From the cell point of view, what signals it to take up more nutrients?

It’s very easy for me to get people outside of the field of nutrition and obesity to see how the problem is not about how much a person eats. If I tell them insulin regulates fat accumulation, they’ll say oh, so carbohydrates make you fat after all. It’s just in the nutrition and obesity field there is such resistance and cognitive dissonance. Not wanting to be wrong, not wanting to admit to yourself and others that you missed the obvious.

I lectured on this at Pennington Biomedical Research Center in Baton Rouge, Louisiana, which is a very influential centre. I gave the talk, Why We Get Fat, which the book is based on. When I was done, one of the faculty raised his hand and said “Mr. Taubes, would it be unfair to say that one subtext of your lecture is you think we are all idiots?” I said, well, I would never say that, I would say that you’ve inherited a paradigm from the generation that preceded you that seemed so obvious that you never thought to question it. And that’s what we all did. And if I’m right, they were idiotic – they should have thought to question it. And they did a lot of damage by not questioning it.

JD: That’s a really bad position for nutrition and obesity experts to be in.

GT: Nobody wants to think of themselves as wrong. I mean, what if I’m killing people? I have a friend who used to joke that if I’m wrong, I’m going to have to go and live in Argentina with all the Nazis who escaped after the Holocaust because I will have killed millions of people myself!

Interview with Gary Taubes – Part One

Gary Taubes is the Robert Wood Johnson Foundation independent investigator in health policy at UC Berkeley and a correspondent for Science Magazine. Heis the author of Nobel Dreams (1987), Bad Science: The Short Life and Weird Times of Cold Fusion (1993), and Good Calories, Bad Calories (2007). His book Why We Get Fat: And What to Do About It was released in December 2010.

Born in Rochester, New York, Taubes studied applied physics at Harvard and aerospace engineering at Stanford (MS, 1978). He received a master’s degree in journalism at Columbia University in 1981. He has written about science for Discover Magazine, Science Magazine, the Atlantic Monthly, Esquire, the New York Times, and many other publications.

JD: What is the central thesis of your books, Good Calories, Bad Calories and Why We Get Fat? How did you come to it?

GT: The central thesis is that it’s not dietary fat that is the cause of nutritional diseases, but the quantity and quality of the carbohydrates that we consume. Along with misconceptions about dietary fat, the nutrition and obesity research community went completely off the rails on the subject of obesity itself and why we get fat. The issue is not one of caloric or energy balance, but of how fat tissue is regulated. It has to do with how the nutrients we eat affect the regulation of hormones that then in turn regulate fat accumulation.

I came to this thesis purely by luck. I was obsessed with this question of how hard it is to do science right and how easy it is to get the wrong answer. When I was researching my first book, Nobel Dreams, I lived in a physics lab in CERN [the European Organization for Nuclear Research] outside Geneva for nine months. There, I watched some very intelligent physicists discover non-existent elementary particles. While I was watching them screw up, I was being tutored on how to do science right by the more pragmatic, better experimental physicists at CERN. I fascinated by this issue. When Nobel Dreams, which was about the mistaken discovery of “super-symmetric” particles, came out in 1986, I thought I would never be able to work in physics again. On page six of the New York Post, the gossip page, Carlo Rubbia, the physicist who was the head of the lab was quoted, calling me an asshole. I assumed this was the end of my science writing career, but instead, when I would interview someone for a story, they would know about my book and tell me “if you think that guy was bad, you should write about so and so.”

So I started doing stories about people discovering non-existent things, who managed to bolster their careers quite a bit as a result. People like Stan Prusiner, who won the Nobel Prize for discovering prions, which Prusiner says are a new form of life that does not require nucleic acid in order to reproduce. To this day, I will never be able to believe that prions are real, and that there is no nucleic acid there.

JD: Prusiner’s work on prions has led to treatments that slow down Creutzfeld Jacob disease. It seems that it was a useful discovery, but it wasn’t the whole story.

GT: That’s the thing. The fundamental claim, that the prion is a protein that doesn’t require nucleic acid to spread and manifest different strains – it’s a remarkable claim that was made about remarkable data, but without the evidence. Science gets screwed up in myriad different ways, and probably always did. Anyway, that was my obsession. When cold fusion happened in 1989, and my editor asked me if I wanted to write a book about it, I was actually living in LA and trying to write screen plays.

JD: You’re not the first one to do that.

GT: No, I know! I had been living in Paris – I wrote Nobel Dreams in Paris, and I wanted to get back there. I lived there off and on for about 18 months. I was very happy in Paris. I did the research for the book in Geneva. I rented an apartment in Paris and wrote it there. I was 29 at the time, and every young writer wants to write a book in Paris. I had an apartment on Île Saint-Louis, overlooking the west bank behind Notre Dame, five stories up over the water. I would write and take a break, sit on the window ledge and smoke cigarettes.

JD: You had the ghosts of Sartre, Beauvoir and Camus in your ear. Not that they would be very helpful for what you were writing about!

GT: Actually I read Hemingway and Solzhenitsyn – The Gulag Archipelago. I kept reading it over and over again because he has a wonderful voice, at least in the translation. So I was writing screenplays and trying to get back to Paris. I was broke, and my publisher asked if I wanted to do a book on cold fusion. I thought it would take nine months, and that I could bank enough money to write screenplays for two years. Instead, I got obsessed with how the scientists could claim to have observed cold fusion, which turned out to be a non-existent phenomenon. I interviewed something like 350 scientists, administrators, and graduate students – anyone even remotely involved with it. I was fascinated at how this could happen.

The underlying rule of journalism that I had been taught is that you want to understand the motivation of all the characters – even those you think misbehaved. You’re done reporting when you feel that you know why what they did seemed to be the only thing they could do. Cold fusion was a fascinating story about science going off the rails. I saw it as a kind of case study that every graduate student should read. Anyway, by the time I was done writing the book, I was $45,000 in debt, and had married a New Yorker. I had moved back to New York. That was the end of my screen writing career and I had to go back to science writing full time.

JD: You did the retirement early. When you were 29 you retired to Paris.

GT: I wrote in Paris. I wouldn’t call it a retirement. I worked constantly. My friends in the physics community said to me one day, “if you think the science of cold fusion is bad, you should look at some of the stuff in public health.” One example is the idea that electromagnetic fields cause cancer. The claim was based entirely on observational epidemiology, which I was fascinated with, because everything I had learned in physics about how to do science right didn’t hold for epidemiology. In physics, negative data is more important than positive data. Data that refutes your hypothesis is what you put more weight on. In epidemiology, if you have negative data, you throw it out. The supposedly seminal paper on electromagnetic fields was a Swedish study that measured electromagnetic field exposures in three different ways. Two of these measurement methods got no effect, so the researchers just left them out of the paper. Then they did their statistical analyses based on the third way of measuring, which is completely bogus. You have to do the statistical analyses based on all three measurements. You can’t just throw out the two that didn’t see an effect and say those weren’t the correct way to measure electromagnetic fields, which is what the Swedes did. What was weird about it is that the epidemiologists didn’t care. Nobody I showed the paper to pointed this out. And I’m just a journalist, remember.

JD: It sounds like the sort of thing that any person who wasn’t a part of the field would have remarked on.

GT: You would think so. So then I did this piece for Science Magazine on epidemiology. At that point, I was becoming kind of a public health writer. One thing led to another and I ended up doing a story on salt and high blood pressure, looking at the data underlying the idea that salt causes high blood pressure. When you’re freelancing, occasionally you just need a paycheque. I called my editor and asked if there was a story that I could turn over quickly because I needed to pay my rent that month. The DASH (Dietary Approaches to Stop Hypertension) study had just come out and someone had given Science Magazine a pre-publication version of the paper. I didn’t know anything about salt or blood pressure, but my editor asked if I could do a one-page story on it. The way you do those stories is you interview the researchers and they give you the names of a few people to talk to who agree with what they’ve done and you talk to those people and you write it up. It’s meaningless journalism. But in this case, somebody had given the paper to Science and that guy had also given some names of people to talk to.

So I interviewed both the people whom the researchers themselves suggested and the people this other guy had suggested. One of those people was the former president of the American Heart Association at the University of Alabama. She told me that she couldn’t talk about the study because she’d lose her funding. At the same time the researchers had recommended that I talk to a preventive medicine expert at Northwestern University. I got the guy on the line and he started yelling at me, saying that there is no controversy over salt; that this was a made-up controversy; that the evidence is clear and concise and definitive. I said – but I’m not calling about salt. I’m calling about the DASH study, which was a dietary way to lower blood pressure that didn’t involve salt restriction. After that, I called my editor and said that there was obviously a controversy over salt and that I was going to report it. So I spent the next year researching and reporting on salt. I published the article, “The (Political) Science of Salt” in Science Magazine. There is virtually no meaningful evidence that salt is the driver of high blood pressure.

JD: I took a course here in Ottawa on social marketing from a very smart communications expert. He has put together a really great campaign here in Ontario called First Words, which is aimed at getting parents to take their children in for speech and language testing at a young age. He managed to get the message about First Words to some very hard-to-reach communities through his campaign. He was talking about other campaigns he might consider taking on, and one them was salt, which he is sure is a dietary evil.

GT: Well, everyone is sure of it, but there is no evidence.

JD: I put my hand up and said that one of the problems is that sometimes you think by doing certain campaigns you’re going to be contributing to the greater good, but you might not be.

GT: That’s what happens. So many people get involved and it becomes a case of people not being able to imagine that the claim is not true. When I was working on the epidemiology story, one of the epidemiologists I interviewed said, it’s not that these problems don’t exist in every science. High energy physics has them and molecular biology has them. But if you do something stupid and misinterpret a paper on recombinant DNA, nobody cares. Nobody changes their life because of it. And nobody else gets involved. But in health fields, everybody gets involved. A lot of very nice, well-meaning people get involved, and get on these bandwagons and then they can’t believe that they’ve been doing more harm than good.

JD: I think it’s because there is a gap between what a person outside of the field can understand and what scientists are supposed to be able to understand. The assumption is that the experts have thoroughly tested their claims and they’re right. A person outside of the field would have a hard time determining whether scientific claims are true or not.

GT: I’ve lectured on the central ideas in my books Good Calories, Bad Calories and Why We Get Fat three different times at the National Institute of Health, to three different audiences. The second audience was the Nutrition Coordinating Committee that really had me begrudgingly. I was foisted on them. They could care less and they sat there so they could say that they heard me out. After I gave the lecture, a young guy who ran a childhood obesity program came up to me and said his major concern was keeping kids off saturated fat because they would be at risk for heart disease when they got older. He said there were thousands of studies confirming that saturated fat causes heart disease.

I said, you know the difference between you and I is that I’ve actually gone back and looked at all that data, and as of 1984 there were no more than nine studies. I could go through each one of them and tell you what they found. And since then, there have been another ten studies and I could tell you what they found and how ambiguous they are. There aren’t thousands of studies, but that is what many nutrition experts believe – it has to be true. Sometimes they are the most vehement – the ones who know the least about the underlying data.

When I wrote the salt story, I encountered the preventive medicine expert at Northwestern that I told you about. That guy is one of the five worst scientists I have ever interviewed in my life. He tells you there is absolutely no doubt, there is no evidence against this, we’ve proven it. He doesn’t understand that there is always evidence for and against hypotheses. If there is a controversy there is obviously evidence against it. In science, you don’t prove things true; you just basically fail to refute them. This expert at Northwestern took credit for getting Americans to eat less fat and eggs, as well as less salt. He and Ancel Keys were primarily responsible for the fat hypothesis—the idea that fat causes heart disease. It was Keys’ hypothesis and this expert at Northwestern embraced it before anyone else did. I told my editor that this was one of the worst scientists that I had ever interviewed in my life, and although I had no idea if there was a story there, I figured if he was involved in any way, there had to be one. I said “when I’m done with the salt story, with your permission I’m going to research the claims about dietary fat and see what I find.”

The science turned out to be terrible and the data was completely ambiguous. The decision to put the entire nation and the world on low fat, high carb diets was politics and wishful thinking more than anything. I did a big piece on dietary fat for Science, and then the famous New York Times Magazine cover story “What if It’s All Been a Big Fat Lie?” The Times Magazine cover story led to a book deal for Why We Get Fat. The more you look in this field the worse the science is and the more there is to write about. If you go and actually look at the data yourself, it’s stunning how bad the evidence is that’s pushed us toward what stands today as the conventional wisdom on diet and disease.