I read Gary Taubes’s new book The Case Against Sugar twice. First I read it in manuscript, then in galley proof. My intention was to write a review of it to be posted around the book’s publication date, but on or just before pub date a dozen other reviews hit the web. Consequently, some of the rush to get a review put up quickly kind of drained out of me. A couple of days ago, I received an email from a fellow blogger, Richard Nikoley of Free the Animal, linking to Stephan Guyenet’s case against The Case Against Sugar and asking me what I thought of it. I read the critique, and, since I had some time on my hands at that moment, dashed off my thoughts.
Richard wrote back and asked permission to publish my email to him on his blog. I was a little dumbstruck, because making the thing public wasn’t my intention when I wrote it. Plus, when I zapped it together, I was stuck in a lobby waiting for someone to show up, so I typed the frigging thing on my iPad. Consequently, it was crawling with typos. I reread it, and thought: Well, maybe it can kind of substitute for the review I was going to write. Especially since there are already so many other reviews out there right now. This one brings a little more personal touch and history since I know all the players involved.
Here is the email as I sent it to Richard:
The stupid are cocksure while the intelligent are full of doubt.
I like it because we all are like atomic particles: we change states constantly. In some aspects of our lives and on some subjects we are intelligent while in others we are stupid. And, consequently, we are either cocksure or full of doubt, depending upon our state.
The older I get, the more I understand how potent the confirmation bias is. And how it is almost impossible to overcome. I’m suffused with it, as are you, and Taubes and Guyenet and just about anyone else either of us can point to. As a result, I never know – for absolute certain – whether I am on the right side of any argument or not. Whether I’m cocksure or full of doubt.
When I was in my middle thirties, I started gaining weight like crazy. Before I knew it, I was 35-40 pounds overweight. Like most doctors, I didn’t know shit about nutrition, so I went on the current fad diet at the time, which was in a book by a physician named Stuart Berger (who later died young and morbidly obese). It was low-fat, and I did okay, but hated it. I lost a bit, then regained. I then went on Pritikin, which I really hated. I think I tried one other diet, also low-fat (those were the only ones in vogue at that time), and it didn’t do me a lot of good. Optifast, a hospital-based fasting program was all the rage then, and I discovered there was a similar program (Medifast) set up to be administered through physicians’ offices, so I sent off for the info with the idea of using it as a means to increase revenue in our clinic. When I got the instructional materials, I read it through them and realized that it sounded suspiciously like a shake version of Atkins, whose book I had read years before and discounted, because the medical profession had badmouthed it. (At that time, I was as mainstream as mainstream can be.) The packet contained a few scientific papers, so I read them. The data they presented seemed convincing, so I decided to do the program myself before putting patients on it. I lost effortlessly, wasn’t particularly hungry, and had no decrease in energy levels as I had experienced with the low-fat, low-cal diets I had tried. Which was interesting, because the shakes themselves were low-fat and low-calorie. So the difference had to have been the carb restriction.
The problem I saw with the program was that the shakes worked great to effect weight loss, but when all the excess fat was lost, the company promoting the program had a low-fat, high-carb diet for maintenance. That seemed strange to me because all the papers that came in the physician starter kit argued for the effectiveness of the program as being a consequence of the carb restriction. If the papers were correct, I couldn’t figure out why the Medifast people thought adding a ton of carbs in for maintenance would do anything but bring about weight gain. So, I redid the maintenance program and designed it low-carb.
My patients, many of whom were overweight, had observed my weight loss and asked me about it. I decided that I would start running my own version of the fasting program and maintenance diet in the clinic. It became a hugely successful operation. I finally decided that if the fasting program worked so well, why wouldn’t a low-carb food program work just as well. So, I tried it. But since that diet contained a lot more fat, especially saturated fat (which was verboten in those days), I was worried about using it on anyone of heart attack age. MD sent me a patient from her clinic and I had a few others that disabused me of that notion.
After my experience with these early patients, I overcame my fear of saturated fat and for the rest of the time I was in practice, I used low-carb diets that I fiddled with and refined to treat an enormous number of patients. Most of those patients had tremendous success with it. MD and I hired on to be one center of a major drug study for the drug that ultimately became Xenical. It was a maintenance study, so we had to recruit patients and put them on a standardized, 6-month lead in weight loss diet which was the state-of-the-art low-fat, high-carb diet, designed by the drug company, to get them to lose enough to be accepted into the maintenance part of the program, during which they were to get the drug. All they had to lose over the six months was four percent of their body weight to qualify for maintenance. A 200 pound woman would have to lose eight pounds over six months to qualify. And I can’t tell you how many of them didn’t qualify. We got paid a fortune to do this study, but the payment schedule was skewed toward the end because the drug company (Hoffman LaRoche) obviously wanted patients to get to the maintenance phase to test their drug, so we did everything in our power short of horse whipping the patients to get them to stay on the program and lose.
One of the problems was that the drug-study patients came and waited in the same waiting room as our regular patients, all of whom were on low-carb diets. They would talk among themselves, and when the low-fat, high-carb, drug-study patients heard how much the low-carb patients were losing (sometimes almost as much in a week as the drug study patients were losing over months), the former became discouraged and wanted to be regular clinic patients instead of drug-study patients. It was a major pain in the ass. But it was extremely informative to me, because I saw first hand the difference in outcome of patients who had extensive nutritional counseling, dietary guidance, a dietitian on call, and weekly office visits (the drug study patients) versus our regular clinic patients on low-carb diets who had a short session on what to eat and came into the clinic once every couple of weeks to weigh in. There was no comparison. The low-carb diet vastly outperformed the low-fat diet, hands down. Better weight loss, better lab values, better sense of well being. Virtually any parameter you want to measure, the low-carbers did better. (The FDA requires study centers to keep all the data for something like 12 years, and I still have it all. I keep thinking someday that I can use it as the low-fat arm of a study or something. It is extensive.)
The point of this long story is that I have many years of experience dealing with low-carb diets, so I have a difficult time believing it when people tell me that low-carb diets are just the same as any other diet. My years of experience, both personally and professionally, tell me otherwise, irrespective of the findings of a few episodes of n=1 bro science here and there. My confirmation bias is damn near set in stone.
So, with that intro, telling you upfront where my bias is and why, let me get to the Guyenet article. Which I almost hesitate to do since I don’t think it really matters much. A year or so ago, I read a paragraph in Scott Adams’s book that changed my mind about engaging in these kinds of things. I think it pretty much sums up the way things are:
If your view of the world is that people use reason for their important decisions, you are setting yourself up for a life of frustration and confusion. You’ll find yourself continually debating people and never winning except in your own mind. Few things are as destructive and limiting as a worldview that assumes people are mostly rational.
So, with that said, here I go:
I’m sure you’re aware of the big brouhaha that took place at AHS11 when Taubes questioned Guyenet during the Q&A after Stephan’s talk. It was kind of chicken shit in that it wasn’t just a Q&A where Gary got in line to ask questions like everyone else. Gary was speaking right after Guyenet (and Gary was the big star of the show) and he took the opportunity as he approached the podium to zing Stephan.
Later that night, Gary, Rob Lustig, and I (maybe you were there by then) were in the lobby of the hotel having a drink when Guyenet walked up. The first words out of Gary’s mouth were, “Stephan, I’m sorry I was such an asshole today.” Stephan blew it off as if there was nothing to it, and we all sat there chewing the fat.
After the conference, the internet went wild with the spat (if that’s what you want to call it) with all these people posting their iPhone versions of it and many of them, maybe most, taking Guyenet’s side. I think it was only then that Stephan thought he had been ill used.
Whatever it was, Guyenet seem to have had it in for Gary since. And it’s a shame since they were friends before. I actually met Stephan though Gary. I happened to be in Seattle, and Gary invited me to a dinner he threw there for Philippe Hujoel, who had invited him to speak at the University of Washington. Gary also invited Stephan and a couple of other people I can’t remember. Now it’s blown up and Stephan has aligned himself with that troll Evie along with James Krieger, Alan Aragon and all the other Taubes haters. So, it doesn’t surprise me that he wrote the review he did.
In my view, he took a lot of disingenuous shots at the book. I’m assuming you’ve never read the book, but I have. A couple of times, in fact. Once in manuscript and again in galleys. It’s like all of Gary’s books. Informative, well-written, and fun to read. Even if you don’t agree with all of it. But I don’t see how you can take a hostile reviewer’s side without reading the book in question to see if the reviewer is on the mark or not.
Gary was straight up at the outset of the book in saying that he was making the case against sugar. It’s even stated in the title: The Case Against Sugar. Not that he was being even handed. Not that he was being unbiased. But that he was gunning for sugar, much like a prosecutor in a trial. He made the point that Big Sugar has a promotional arm that spends hundreds of millions of dollars to make its case – he is simply making the case for the other side. And he basically ends the book by saying he hasn’t made the definitive case – all he has to go on are observational studies and poorly done, short RCTs. To really determine if sugar is causative would require years of randomized controlled trials, which would be prohibitively expensive, and impossible to monitor. The short term trials have been kind of bad for sugar, but that’s all they are: short term trials. Gary admits as much. Guyenet seems to be trying to make it out that Gary is definitively saying all the evidence is in and sugar is bad, when that’s really not the case. He’s simply presenting the anti-sugar case.
(If you read anything that Big Sugar has put out in the last few years, they are making their case – such as it is – by saying that sugar is simply calories, nothing more, nothing less. It’s a calorie just like an apple or a potato or a strip of bacon. In their view, a 2,000 kcal diet of meat, squash, and blueberries would be equivalent to a 2,000 kcal diet of pure cane sugar.)
Gary starts by presenting a history of sugar and the sugar industry. He discusses how the Dept of Agriculture was founded in large part to promote large ag industries, one of which was sugar beets. He also points out how in the early days there was a revolving door between the Dept of Agriculture and Big Sugar, just like there is now between the FDA and Big Pharma. And he describes many of the techniques Big Sugar used to increase the use of its product.
Recent internal documents from Big Sugar have come to light and were just published in the JAMA Internal Medicine (2016y Kearns Sugar Industry and Coronary Heart Disease Research A Historical Analysis of Internal Industry Documents) showing that the sugar industry did indeed influence and promote the idea that saturated fat was bad in an effort to deflect attention from themselves. They spent a ton of money underwriting Frederick Stare, Hegsted, Keys and others to push the notion that saturated fat was the devil and deflect the attention from sugar. (The lead author on this study was one of Gary’s research assistants, whom he paid to travel to Boston to gather the documents. After leaving Gary’s employ, she wrote the paper and went through the peer-review process to get it published.)
I’m not going to go down Guyenet’s list one by one, though I could, but there are a couple of areas I will mention in which I think he is stretching it more than a little to make his point.
One is in saying that restricting calories will reduce insulin levels. Well, yes, sort of. But not by any stretch of the imagination to the extent reducing carbs will. A metabolic ward study published in 1996 shows pretty clearly this isn’t the case. Subjects in both arms went on 1,000 Kcal diets (low-calorie diets by anyone’s estimation) for 6 weeks. One arm went on low-carb, the other on 45 percent carb (which compared to the ~55% carb in the typical American diet isn’t that high-carb). Those on the calorie-restricted low-carb diet reduced insulin levels by about 50 percent, whereas the ones on the 45% carb diet slightly reduced insulin, but not to a statistically significant extent. (1996y Golay Reaven Similar weight loss with low- or hgh-carbohydrate diets)
As to the mentions of Kevin Hall, suffice it to say that that whole situation is mired in controversy, which won’t be resolved for a long time. Even I wrote on it. There is gotcha history there, and Gary probably shouldn’t have hired Hall in the first place. We can discuss the whole affair over a brew sometime.
On the findings of metabolic ward studies, I had that go round with Colpo here and here.
And pointing the finger at the addictive qualities of sugar (should they exist – and Gary admits the jury is out on this) is not confirming the food reward theory. There is a real but subtle difference.
One of the questions Gary proposes is this: Is there an amount of sugar the consumption of which becomes deleterious for health? He reports on a number of researchers throughout the world who have asked this same question. If you look at sugar consumption per capita, people seem to be okay as long as the per capita consumption doesn’t exceed a certain level. I don’t have the book in front of me now, but, as I recall, these levels are in the 50-70 lbs/person/year, which is a helluva lot of sugar (I doubt that I consume five pounds per year, if that). When the people in a country start to exceed those levels of intake, though, diabetes starts to appear and increase at rapid rates. Gary didn’t make this up – he’s simply reporting the findings of other people.
One of the effects of the confirmation bias is that so many issues are never solved until the evidence on one side is so overwhelming that it has to be believed. It takes a long time for the evidence to stack up to that extent, though, so it takes forever for people to finally come together.
It can happen individually, as in the case of Tim Noakes, who is an internationally renowned sports doc. He wrote the early books on running and endurance exercise. Was a big believer in carb loading and wrote about it extensively. Until he developed diabetes. Then he tried low-carb, and changed his life.
It takes a lot longer for the profession in general, but it is coming around.
Anyway, many of Stephan’s criticisms would be on point if Gary hadn’t already admitted to them in the book, so they’re not really valid criticisms. It’s not like Gary is trying to pull the wool over anyone’s eyes.
So, that was the email, which really wasn’t a review of Gary’s book as much as it was a defense of it. I’ve read many of the reviews circulating around out there, so let me give you my take on the book, which is a little different.
Does Sugar Damage Metabolic Flexibility?
Metabolic flexibility, in technical terms, is defined thus:
The concept of metabolic flexibility describes the ability of skeletal muscle to switch between the oxidation of lipid as a fuel during fasting periods to the oxidation of carbohydrate during insulin stimulated period.
More simply put, metabolic flexibility is a measure of the body’s ability to successfully deal with all incoming foods, irrespective of macronutrient composition. If you’ve got a lot of metabolic flexibility, you can pretty much chow down on whatever you want and not suffer any immediate consequences. If you eat fat, some is burned, most is stocked away till later. Same with carbs. You burn what you need, then store the rest as glycogen. What about both fat and carbs? Generally, you burn the carbs first, store the rest and store most of the fat. The point is, if you’ve got good metabolic flexibility, you can eat most anything and not suffer immediate consequences from it.
Unfortunately, unlike love and herpes, metabolic flexibility isn’t forever. Most of us experience a decline in metabolic flexibility as we age. But it takes a while, which is why children seem to be able to eat anything they want without paying the Piper (immediately, at least). Most of us adults aren’t so lucky. Sadly, many children aren’t either since rates of type II diabetes (formerly called adult-onset diabetes) are now increasing in children and adolescents.
Under normal metabolically flexible conditions, eating carbohydrate stimulates the pancreas to release a little insulin, which drives oxidation of the carbs needed for immediate energy and storage of the rest. When metabolic flexibility doesn’t work so well, the carb meal stimulates the release of insulin, which often isn’t enough to store away all the carb, and the blood sugar rises. The pancreas releases more insulin, which may or may not be enough to get the blood sugar down. Ultimately, someone who loses metabolic flexibility can find him/herself having both elevated insulin (hyperinsulinemia) and elevated blood sugar. We call this type II diabetes. It is often associated with obesity and the other disorders that are collectively called the metabolic syndrome.
There is a continuum running from mild glucose intolerance to full-blown diabetes and everything in between. The end result we diagnose as glucose intolerance, diabetes, metabolic syndrome or whatever. The cause is a decrease in metabolic flexibility.
No one really questions the idea of metabolic flexibility, or its decline with age. They do question why it happens. Why the decline? Why do some people have a minimal fall off with age, while others have a massive fall off and succumb to diabetes, obesity and all the rest. What makes people convert from being metabolically flexible to being metabolically INflexible?
Since the vast majority of people with metabolic inflexibility respond quickly and often completely to carbohydrate restriction, many, myself included, believe that carbohydrate overconsumption may be the cause.
Those of us who believe in this theory fall into one of three camps. One I call the Yudkin camp (after the British physician and nutritionist John Yudkin), the second the Cleave camp (named after Thomas L. Cleave, another British physician), and finally the all-carbs-are-bad camp that I don’t have a published Brit author to name it after.
Yudkin thought sugar was the initiating problem. Cleave thought refined carbs, mainly wheat and sugar, were the initiating problem. Those in the third camp believe all carbs are bad.
The three camps differ in what they believe is the cause, the triggering event, so to speak, but they all agree that once the problem sets in and metabolic flexibility is lost, and the only way to successfully treat the problem is with a low-carb diet.
This is where Gary Taubes’s book, The Case Against Sugar, enters the picture. He is making the Yudkin case, although using a ton more research than Yudkin had available to him during his lifetime.
Gary musters a mountain of evidence that until various societies are exposed to sugar, diabetes, the signature feature of metabolic INflexibility, is rare. Once sugar is introduced into a society, nothing much happens at first, but as the amount of sugar eaten increases, cases of diabetes start popping up. Ultimately, when the sugar consumption is at high levels (in the US it peaked in 1999 at about 90 pounds of sugar per person per year and has fallen off slightly since), diabetes becomes epidemic.
(NB: Remember, the 90 pounds/person/year is an average. I doubt that I eat five pounds of sugar per year, which means someone else is eating 175 pounds per year to make the average work. It is those people who are doubtless the ones filling up the diabetic wards.)
Stephan Guyenet and others have attacked Gary because the data he musters comes from observational studies and short-term, often poorly done RCTs. The reason is that this is all the data that are available.
To truly nail this down, scientists would have to randomize people into two groups, the subjects in one of which would be expected to eat 100 pounds of sugar per year, while the subjects in the other group would eat almost no sugar (or a significantly lesser amount). The study would have to last for years to realize a significant outcome. Ethical issues aside, a study like this would be enormously expensive and would be impossible to accurately monitor. It’s one thing to randomize people into a study and have them not eat sugar for a month or six weeks – it’s entirely another to get them to forsake it or gorge on it for six years (or however long it would take for meaningful data to emerge).
You have to do it kind of like the studies on smoking were done. For ethical reasons, you couldn’t randomize non-smokers into a group and make them start smoking to compare outcomes with those who continued to smoke. Researchers had to rely on observational studies and animal studies, all of which strongly implicated smoking as a major driver of lung cancer.
As I mentioned in the email above, The Case Against Sugar is a standard Taubesian work. Compulsively readable and filled with all kinds of engaging and thought-provoking history. He veers off here and there to discuss the invention of ice cream and the origins of the candy and soft drink empires that exist today. And that’s not to mention the breakfast cereal industry, which, unfortunately, was the source of many of my own calories in my youth.
Can you guess the name of the first sugar-coated, pre-sweetened cereal? It was Ranger Joe, developed by a Philadelphia heating-equipment salesman, who got the idea from watching his own kids ladeling spoonful after spoonful of sugar onto their dry cereal. The founder could never get the clumping problems fixed, so he sold out in 1949 to the company that became Nabisco.
The Deadly Duo: Tobacco and Sugar
Another fascinating rabbit trail Gary takes us down is the unholy alliance between big sugar and big tobacco. By blending tobacco cured two different ways – both involving sugar – cigarette sales skyrocketed. The addition of sugar to tobacco made cigarette smoke easier to inhale and vastly more addictive. Before I wrote the email above that kicked this post off, Cato Unbound, a debate or discussion forum that is part of the Cato Institute, asked Gary to write an essay based on his findings on sugar. The editors of Cato Unbound then found three people to write responses. The three people were Yoni Freedhof, a Canadian physician (best known to readers of this blog as the physician who took the video of Kevin Hall and asked the fawning questions), Stephan Guyenet, whom we met in the email above, and Terence Kealy, whom I don’t know, but is a physician and biochemistry researcher.
Here is a short video of Gary explaining the process:
Taubes responds to Guyenet.
After all the critiques were in, Gary was allowed to answer them all.
At the time of my email above, Gary’s lead essay along with the three responses were published. Since that time, Gary has responded. I’ll let the readers come to their own determination as to whether Gary adequately answered his critics, the main one of whom is Dr. Guyenet.
Here is Gary’s essay:
Unintended Consequences, Special Interests, and Our Problem with Sugar
Stephan Guyenet’s response:
Americans Eat Too Much Cake, but the Government Isn’t to Blame
Yoni Freedhof’s response:
Unintended Consequences, Special Interests, Sugar, and a View from the Clinical Trenches
Terrence Kealey’s response:
Putting Nutrition Claims to the Test
Gary’s response to the above:
The Case against Sugar Isn’t So Easily Dismissed
Since I started working on this blog post, two more responses have come in from the folks debating this issue. One more from Dr. Guyenet and one from Dr. Freedhoff. Here are the links to those. I’m assuming Gary will respond. When he does, I’ll post it.
Stephan Guyenet’s second response:
Extraordinary Claims Require Extraordinary Evidence
Yoni Freedhoff’s second response:
Complex Multi-Factorial Problems Tend not to Have Simple Singular Causes
My advice is to not sit on the sidelines as observers to this spat. Read The Case Against Sugar yourself and come to your own conclusions based on how strong you believe the evidence to be.
Before I wrote the email above that kicked this post off, Cato Unbound, a debate or discussion forum that is part of the Cato Institute, asked Gary to write an essay based on his findings on sugar. The editors of Cato Unbound then found three people to write responses. The three people were Yoni Freedhof, a Canadian physician (best known to readers of this blog as the physician who took the video of Kevin Hall and asked the fawning questions), Stephan Guyenet, whom we met in the email above, and Terence Kealy, whom I don’t know, but is a physician and biochemistry researcher.