SETH: You wrote that New York Times piece, and from my take on it, you had a bunch of evidence, and then you got a book contract. Is it fair to say that you found out that what you wrote in the piece was mostly right?
GARY TAUBES: It’s a difficult question. I had actually pitched the New York Times piece on fat as an attempt to determine the cause of the obesity epidemic. The proposal was very open ended. I had several ideas. I actually believed, going in to the story, that the answer was going to be that high-fructose corn syrup was responsible for Americans getting fatter over the last 30 years.
SETH: I’m glad to hear that.
GARY TAUBES: The thing about the obesity epidemic is that we can say when it starts, give or take five years: sometime between the mid-1970s and late 1980s. So we have a starting point, and that happens to coincide with the introduction of a type of high-fructose corn syrup known as HFCS-55, which was developed to taste exactly like sugar when it’s put in sodas and juices. In fact, it is effectively identical to sugar, as far as the body is concerned — sugar (sucrose) is 50-50 glucose and fructose and HFCS-55 is 45 percent glucose and 55 percent fructose — although I didn’t know that when I pitched the article. But I thought that high-fructose corn syrup is so cheap. Basically this is an idea that Greg Critser in a book called Fat Landpicked up on, and subsequently Michael Pollan, too, that high fructose corn syrup allows you to saturate the market with sugar, without any fear that price fluctuations will cause you to go out of business, or lose you a lot of money. If the international price of sugar suddenly spikes, as it did in the 70s, and you’re committed to fulfilling this enormous demand for sugar you’ve created, then you’re in trouble. But if you have a cheap reliable source of sugar, at a price that won’t change from year to year, then you can create an enormous market without fear. This was, more or less, my naive idea of how the economics of HFCS might have caused an entire nation to get fat. Once they had this dependable low-cost sugar substitute, the sugar industry and the soda industry could then expand their production and sell Big Gulps, etc. Then I did the reporting. I talked with industry analysts, and they said that was nonsense; that the primary cost of selling sodas and fruit juices is the bottling and the shipping, and that the cost of the sweeteners is such a tiny portion of the cost of the end product that it wouldn’t have made any difference whether it was sugar or high-fructose corn syrup. So I moved to my next idea, which was based on the fact that the beginning of the obesity epidemic coincided with the institutionalization of the low-fat dogma.
As I’m doing that reporting, I stumbled upon what was, at that time, five trials of the Atkins diet, all of which had been finished, but not yet published. At one point, when I was doing the reporting, I actually got worried that some other journalist would beat me to the punch.
SETH: What was it about the Atkins diet that made these trials so important to your article?
GARY TAUBES: Well, remember, my background, as a journalist and in school, was more or less in physics. In the kind of physics I used to write about, you’ve got some complicated detector that’s looking at particles and atoms smashing together inside it and you’re looking for some byproduct of a collision that you’ve never seen before. A new particle. But the first thing you have to do is make sure you understand your detector. Can you believe what it’s telling you? So you to have to calibrate it. If you want to know how much you weigh, for instance, one thing you might do before you step on the scale is you calibrate that. You make sure that when you’re not on it, the little arrow on the scale is pointing to zero. If it’s registering one or two pounds when you’re not standing on it, then it might be off by five or ten pounds or more when you are. So you want to calibrate your equipment. You want to know that when you set it to zero, it says zero. That’s an idea that’s always resonated with me. Measure what happens at an extreme, make sure you understand that, and then see what happens from there. So here’s the Atkins diet: in theory, you’re removing virtually all of the carbohydrates, but you don’t tell people to eat less. You tell them to eat as much as they want. It’s like you’re setting the diet to zero carbohydrates, and as much fat as possible. According to conventional wisdom, you should certainly not lose weight and you might even gain it. But here were five studies saying that, lo and behold, people really do lose weight when you remove the carbohydrates from the diet, and they lose more weight than they do when you tell them to keep the carbohydrates but eat less calories. What’s more, their cholesterol profiles actually improve, so how can fat or saturated fat be bad for your cholesterol, if these high fat, high saturated fat diets make your cholesterol levels better. To me that had to tell you something about the validity of the low-fat dogma and about the underlying physiology. What do carbohydates do, and what does their removal do. So once I learned about those five studies, I was confident that I had a story that was now worth writing. As for your original question, about whether I found out most of what I originally wrote was right, obviously the book supports the message of the article, but I no longer believe a fair number of things I believed when I wrote that story. For instance, when I wrote the Times article I inherently believed that the key was still calories consumed.
SETH: You mean things that you believed then, that you don’t believe now?GARY TAUBES: Yes, that I don’t believe now. In that original article, I discussed what David Ludwig has argued — that easily digestible carbohydrates cause these blood sugar and insulin spikes, and that in turn causes blood sugar to plummet, and the result is blood sugar so low a few hours later that this in turn makes you hungry. So you eat more and that’s why you get fat with carb-rich diets. Ludwig works with obese children at Harvard and I believed that his hypothesis was probably true. Then I also talked about Michael Schwartz’s research at the University of Washington. Schwartz believes that insulin’s primary role is to suppress hunger in the brain, but that somehow we become resistant to that effect and so, once again, we eat too much and that’s why we get fat. Both these theories are predicated on the notion that we get fat because we eat too much and that’s what I believed. We consume more calories than we expend and we get fat; something about carbohydrates facilitates that excess consumption. Now I believe the causality is reversed, and that’s what I discuss in the book and in the lecture. Carbohydrates make us accumulate calories in our fat tissue, and that in turn makes us eat too much. It’s all about the regulation of fat metabolism. All those things that Ludwig and Schwartz were talking about might have been true (I mean, they are true, on some level), but they’re not the driving force of why we get fat, or why removing the carbohydrates makes us lean.
SETH: I see. So that’s a good summing up of what was in your article that you believe, and what you don’t believe anymore.
GARY TAUBES: There are other related facts, as well. I never imagined when I wrote that original article that I would come to believe that exercise won’t make you lose weight, even though I’ve been an athlete my entire life and it’s never helped me. So it’s fair to say that when I wrote that New York Times article five years ago, I had an entirely different conception about the causes and cures of obesity and overweight. Carbohydrates were key, but my understanding of the mechanisms was completely different. That’s the kicker with research and reporting: you don’t know what you’ll find until you do it.