Gary Taubes strikes back
The Letters section of today’s New York Times Book Review carried Gary Taubes’ rebuttal to Gina Kolata’s self-serving review of Good Calories, Bad Calories. I was glad to see Gary strike back the way he did because it saved me some work.
In her review published earlier this month Kolata took Taubes to task for his conclusion that all calories don’t act the same in terms of how easily they make one gain weight. She accused him of ignoring specific studies done 50 years ago that she felt showed decisively that a calorie really is just a calorie irrespective of what it’s made of.
It’s known, though, that the body is not so easily fooled. Taubes ignores what diabetes researchers say is a body of published papers documenting a complex system of metabolic controls that, in the end, assure that a calorie is a calorie is a calorie. He also ignores definitive studies done in the 1950s and ’60s by Jules Hirsch of Rockefeller University and Rudolph Leibel of Columbia, which tested whether calories from different sources have different effects. The investigators hospitalized their subjects and gave them controlled diets in which the carbohydrate content varied from zero to 85 percent, and the fat content varied inversely from 85 percent to zero. Protein was held steady at 15 percent. They asked how many calories of what kind were needed to maintain the subjects’ weight. As it turned out, the composition of the diet made no difference.
A number of readers of this blog wrote comments asking me about these Hirsch-Liebel studies, curious if they really did show what Kolata reported that they did. I planned to write a post on this paper (it is a single paper, not papers) because Kolata totally misinterpreted it. But Gary saved me the effort because he provided the exegesis in his letter to the editor.
Rudolph Leibel and Jules Hirsch did not, as Kolata says, do the studies in the “1950s and ’60s,” when Leibel would have still been making his way from grade school through medical school. Rather, the study — singular — published in 1992, was a reanalysis of data gathered (on only 16 subjects) originally by Edward Ahrens of Rockefeller University. Ahrens was not studying weight regulation, ironically, but the ability of carbohydrates to elevate triglyceride levels and so increase heart disease risk. The Leibel-Hirsch paper itself argues against the use of the term “definitive” to describe it — i.e., it is rife with caveats. Among them, that Ahrens’s subjects could have gained 15 pounds a year from a unique fattening effect of carbohydrates — 150 pounds of excess fat in a decade — and Leibel and Hirsch’s analysis would have been unable to detect it. Moreover, only one of Ahrens’s subjects was obese, which means, as Leibel and Hirsch explain, that “similar results might not have been obtained in a group of obese individuals or lean individuals susceptible to obesity.” Since the hypothesis I discuss in “Good Calories, Bad Calories” is intended to explain the cause of obesity in precisely these individuals, it is odd to undercut my credibility by accusing me of leaving out a study that did not actually address that issue.
Here is the full text of the Liebel-Hirsch paper so that you can read it and draw your own conclusions.
If you decide to read this 1992 study yourself, I’d like for you to notice a couple of things. As Gary points out, this is not a paper reporting an actual study, but is a retrospective look at studies done 30-40 years earlier. The authors were looking to see if diets higher in fat tended to cause obesity. They selected subjects from these decades old records who were given diets differing in the ratios of fat and carbohydrate while keeping the protein constant. Liebel and Hirsch observed from these records that the group of specially selected subjects (more about which in a moment) maintained their weight on a specific number of calories regardless of the ratios of fat to carbohydrate. In other words, the researchers from years before had fed these subjects enough food to allow them to maintain their body weight within a small range and discovered that it didn’t matter what the composition of the diet was, the subjects required the same number of calories whether mainly carbohydrate or fat were provided. From this Kolata and others have drawn the conclusion that it doesn’t matter what the calories are made of since these subjects maintained their weights no matter what the macronutrient composition of the diet was. But there are a couple of flies in the ointment.
First, the six subjects who consumed the least amount of carbohydrate in the studies got 15 percent of their diet as carbs, 15 percent as protein and 70 percent as fat. And, on average, they got somewhere in the neighborhood of 10,000 mJ per day of energy. Since 4.1868 kcal equals 1 mJ, we know that they got an average of about 2400 kcal per day. 15 percent of 2400 kcal gives us about 360 kcal as carbohydrate. We know that a gram of carbohydrate is 4 kcal, so 360 kcal represents 90 grams of carbohydrate. Based on my clinical experience, I can tell you that 90 grams of carbohydrate is not a weight-loss amount. Most people need to get down around 50 grams or below to lose any appreciable amount of weight, especially if they’re consuming 2400 kcal daily, which is about the number of calories in the average non-weight-loss diet. So, it’s not really surprising that these people required the same number of calories to maintain as those did with higher carbs.
Second, if you look at last paragraph at the bottom of the left column on second page of the study, you’ll see the following sentence:
For inclusion in this analysis, each period of formula feeding had to be ≥ 2 wk and the subject had to have remained weight stable (to within 1 kg) within that period.
This means that in selecting the subjects for this study, the authors purposefully left out those who had not maintained their weight on whatever dietary regimen they were on. We don’t know if those not selected for the study gained or lost weight on isocaloric diets with lower or higher carbohydrate content. Since all the patients in this published paper were selected because they did not have a variation in their weights with diets of differing macronutrient compositions, it seems a little bizarre to me to use this paper to ‘prove’ that a calorie is a calorie.
But Gina Kolata would never let a little thing like this stand in her way. She tries to obfuscate Taubes’ refutation of her interpretation of the paper by replying:
Jules Hirsch, who in fact says he did do the study, said he and Rudolph Leibel published the data in 1992 precisely to counteract arguments like those made by Gary Taubes.
Say what?
Let’s look again at what she says in her review of Oct. 7:
He also ignores definitive studies done in the 1950s and ’60s by Jules Hirsch of Rockefeller University and Rudolph Leibel of Columbia, which tested whether calories from different sources have different effects.
She clearly says that Hirsch and Leibel did these studies in the 1950s and ’60s. As Gary pointed out, Liebel would have been in grade school at that time, so it is unlikely that he was involved. Leibel and Hirsch went back and looked retrospectively at data Edward Ahren’s had gathered 30-40 years earleir and published it in their 1992 study. If you look at this Liebel-Hirsch study you will find that they referenced two papers in stating where they got their data (#10 & #11). The first paper includes Hirsch as a coauthor along with Ahrens, but the second is Ahrens alone. If you look at the Ahrens-Hirsch paper, published in 1959 in The Lancet, you will find that it was a study of only two subjects, neither of whom had their weights listed. At most only two of the subjects could have come from studies that Hirsch was involved in. So Hirsch didn’t do the studies on the majority of the subjects discussed in the 1992 paper, Ahrens did.
It is likely that Kolata called Hirsch, who is now 80 and a real calorie-is-a-calorie advocate, and got him to back her up. Either Hirsch is stretching the truth or Kolata is misrepresenting what he told her about who really did the studies a half a century ago.
Kolata goes on to say in her refutation of Gary’s rebuttal:
Taubes says in his book that calories from carbohydrates are intrinsically more fattening, so this is a central question. The authors conclude: “Variations in fat intake from 0 percent to 70 percent of total energy under conditions of equal energy intake produced no significant changes in body weight over periods of observations averaging 33 days.” In other words, a calorie was a calorie was a calorie.
Um, yep, Gina, the weight doesn’t change no matter what you feed the subjects if you’ve selected for inclusion in your paper only subjects who showed no weight change. It doesn’t mean squat.
She goes on to smugly say the following:
As Taubes amply documents in his book, low-carbohydrate diets have been popularized periodically since the 19th century. Best-selling book after best-selling book promoted them. Yet if they work so well, why are so many people still searching for an effective way to lose weight?
Why not indeed, Gina?
Could it maybe be because you and Jane Brody and Marian Burros and diverse other idiots are out there telling everyone that low-carb diets will kill them? It’s difficult enough to stay on any diet in the face of constant naysaying, but in the case of the low-carb diet the naysaying is particularly heinous. People are told that they are clogging their arteries, damaging their kidneys, leaching calcium from their bones, ruining their livers and God only knows what else. Committed low-carbers can see through all the smoke and mirrors, but these folks are a minority. Most people who diet want to lose weight while getting on with their lives. They don’t want to make a study of the biochemistry and physiology of metabolism, they simply want to drop a few pounds. And for the most part they’re not all that dedicated, so it doesn’t take too many people telling them low-carb horror stories derived from all the myths Kolata and her henchmen promulgate to make these folks throw up their hands and go back to carbs.
It annoys me that the Times gave Kolata the space to attack Gary yet again. She wrote the poorly-researched hatchet-job review of the book in the first place. Gary should have been allowed his rebuttal without her refutation of his rebuttal. That would have been equal time for all, with her getting four times the space that Gary did. But that’s not the way the media works when one of their own is attacked. Nor is it the way the media works in general when one of its shibboleths – in this case, the idea that carbs may be unhealthful – is under attack. When I read Gary’s letter and Kolata’s response I was in the middle of a post on how the media denigrates anything with which they disagree while appearing to be fair and balanced. I’ll go ahead and put up the post in due course, but this exchange is a perfect example.
I went to The Grain Blog and left this comment–it’s still awaiting moderation–wonder why.
I LCforevah says: Your comment is awaiting moderation.
November 1st, 2007 at 11:09 am
It seems to me that everyone who is criticising Taubes’ work hasn’t read it. It is not a diet book. It is a critique of nutrional science starting 150 years ago and coming to the current era, showing how almost all nutritional studies presently being done are so flawed as to be useless. Yes, there – I said it – useless.
Carol, Taubes is a science journalist. This is what he has always done, from undergrad to graduate work. He has won three awards for his efforts. I would always take the work of a third party like him, rather than the nutritionists whose egos have too much at stake in the outcomes of their work. Let me tell you, that after reading the book, the phrase “nutrition science” has become an oxymoron for me. Taubes, being someone involved in science, is much more circumspect as to how he presents the nonsense.
I’m a layperson and not involved with any kind of scientific endeavor. I can only offer what is a personal anecdote and tell you that the best thing I have ever done for my health is to give up wheat and dairy. I no longer have brain fog, sleepiness, sinus headaches, swelling of the extremities, joint pain, and the list goes on.
The human animal is always presented as an omnivore, but I think it would be more nuanced to say that there is a continuum where some humans are on the carnivore side, while others find themselves on the vegetarian side. I have certainly and happily found out that I am a carnivore and now act on it.
Hey LC–
Your comment there may languish longer than comments do here.
Nice work.
Cheers–
MRE
“a calorie is a calorie is a calorie” rather makes my mind echo like “an idiot is an idiot is an idiot”…
Have read Taubes book (already knew most of it after 3 years of LC-eating – strange that you have to become a semiscientist to be allowed to eat naturally?) and really enjoyed it!
Agree with LCforevah: I am a carnivore!
I hope you’ll write to the NY Times about this. Perhaps they’ll print your letter and add another voice to the reasoned side.
It is very doubtful.
Cheers–
MRE
I think what Taubes has provided for those who believe in LC, is the ability to stop thinking about, defending, explaining and subconsciously doubting it. In other words, it gives us the freedom to be comfortable in our own thin bodies and skin without being thin-skinned. After reading the book, I no longer really care to engage in a discussion with doubters or curiosity seekers who have swallowed the conventional advice over my nutritional intake. I don’t care if anyone believes in it, thinks I’m stupid, careless, misguided. whatever. Taubes’ treatise combined with people like Eades and Atkins and combined with our own experience and common sense gives us all we need to “drop it” and go on merrily with the rest of our lives.
I do think Taubes misses some important points that would be useful in furthering his premise.
First of all, one of the main flaws in nutritional advice (I will not call it science) is that it is all geared toward a one size fits all approach. Humans are genetically very diverse in so many dimensions yet nutritionists nearly universally offer advice as if we were all metabolically identical; we’re not, any more than we all have the same shoe size or eye color or whatever. Taubes misses this point in saying that restricting carbs is probably good for everyone. I suspect there are some people for whom restricting or not restricting carbs is relatively neutral and people for whom it is immensely beneficial with people all along the spectrum. There may even be certain people for who restricting carbs is detrimental.
I would like to assert some intuitive facts that may or may not be proven by the current research that has occurred but am willing to bet money with any taker on their correctness.
1) There are many millions if not billions of people whose metabolisms function in such a manner that a true persistence of restricting carbs (a la Atkins or Eades) will make them leaner and healthier in many important dimensions.
2) That this phenomenon is correctly identified as an insulin mediated response.
3) A calorie is a calorie is a calorie is a true statement – but irrelevant to human metabolism. This statement is true of a perfect thermodynamic processor – something that humans are not. There is no question that those people who fall into the category described in point 1 above can eat more calories while remaining leaner by restricting carbs. Likely, category 1 people will be fatter on a lower calorie diet that is 70% carbohydrate than a higher calorie diet that is 5% carb. This will not be true for people whose genetically different metabolisms are far from the category 1 type.
In the absence of insulin, the body clearly does not “process” as many of the calories that are available to it through what is consumed. In this case “process” can only mean use directly and immediately for energy or store as fat. Also, never mentioned is the fact that the body’s excretions have thermodynamic content. Animal exretions are good fertilizers precisely because they contains energy that can be used by plants and other organisms. The body exretes what it doesn’t convert to energy or store as fat. This is the reason that – for the human body – a calorie is not a calorie is not a calorie.
If someone wanted to make a true statement based on physics it could be this: Body weight is perfectly correlated to the mass of what’s consumed minus the mass of what is excreted (in the various forms – solids, liquids and gases). I don’t think this needs elaboration. It’s obvious and is so axiomatic that it doesn’t need proof. The concept that the body is a perfect thermodynamic processor cannot be proven.
It is funny and illuminating at this point to see how typical, nay rampant, for people to opine vigorously with severely limited knowledge or none at all. On the other hand, it is kind of scary.
Hi Marc–
Just a couple of comments on your comment. First, the idea that we are all different is true to a certain extent. But we are all a heck of lot more similar than we are different. Although I’m tall and white, my pancreas makes the exact same insulin as that of a pygmy who is short and black. The parietal cells in my stomach work the same as his as do the alveoli in both our lungs. If you give me enough arsenic, you’ll kill me. The same goes for him. The doses may be a little different, but the way the drug acts will be the same.
Second, the idea that weight in minus weight out (as solids, liquids and gases) equals weight loss or gain doesn’t really work either. Why? Because we convert a lot of incoming food energy into heat, which isn’t a solid, liquid or a gas. And we simply waste energy by running futile cycles, which calculates in as weight loss. The laws of thermodynamics apply perfectly; we just haven’t figured out all the pathways yet.
Cheers–
MRE
From Marc to Mary,
Thanks for the elaboration and I would suggest we still agree but that I failed to fully articulate some important distinctions.
First of all, you are correct that heat is another pathway through which consumed energy can leave the body. Consumed calories can leave the body as matter containing thermodynamic content or as heat and few other nits and nats. The point remains that the proponents of a calorie is a calorie make the assumption that the thermodynamic content of all food that enters the body does one of two things – support work done by the body with very little wasted efficiency or store it as fat. That is not the case. How the body handle sthe thermodynamic potential of the foods consumed by the body is much more complicated than that and is dramatically effected and mediated by insulin, particulary with respect to lipogenesis.
With respect to genetic diversity, I agree with your comment that we have the same basic mechanisms for metabolism, but please allow me an example to illustrate my point. Some of the biggest skeptics of low carb regimes (other than the entrenched nutritional/medical establishment) are people who for some reason can consume rather copious calories with high carb content and not have any trouble remaining trim. I call these people metabolically gifted. My wife is one of those (and I know many others). She is 5′-7″ and 110 pounds. She consumes probably 2200-2800 calories per day consisting of about 60% carbs. She eats bagels and cereal for breakfast, sandwiches or buttered baguettes for lunch and meat and mashed or baked potatoes or white rice for dinner all the time, snacks on crackers all day long, eats lots of chocolate and frequently has desserts – ice cream, cake and the like. She never gains weight and has a reasonable lipid profile. I on the other hand must keep my carb consumption down around 25-60 grams per day consistently or I will gain weight and stabilize at around 25 pounds of additional body fat. If I maintain the carb restriction, I can consume 2500, 3000, 3500 calories a day, it doesn’t matter and stay trim and feel good. If the carb content goes up to 100 g/day I will gain weight consistently up to the 25 pounds even at 2000 cal or less per day. Therefore, there must be some genetic difference in the way our bodies respond to carbs – either I produce more insulin or I am more susceptible to developing insulin resistance or something. That is why I say there are genetic variations in the degree of impact carbs have on obesity from one person to the next. That doesn’t mean there aren’t other aspects outside of obesity where the carbs are negative for those less likely to become obese in response to carbs. But as to the obesity question, I think there is a genetic continuum as to the sensitivity to carb intake and lipogenesis because I obsserve in people the ability to eat in way I can’t without gaining weight. You have helped many people, including me. Protein Power was my introduction to LC and it has been a godsend. I know it’s right for me and metabolically and scientifcially sound and I no longer feel compelled to defend it or even discuss with skeptics or conventional nutritional wisdom nazis or the “metabolically gifted.”
Thank you
Thank you,
Marc
The way you wrote it this time I agree with completely.
Best–
MRE (for Michael R. Eades. That’s Mike, not Mary)
Gary Taubes does address the subject of genetic predisposition to fat by emphasizing that fat accumulation is under hormonal control (insulin) rather than a simple positive balance of calories. He also used the example of different fat distribution in women and men as evidence that genes are at work in both the book and his UC Berkeley lecture. Perhaps he didn’t state it explicitly, but that is my understanding when he discussed why certain people are more prone to obesity than others even when they ate less calories.
Hi Richard–
I think that is exactly what he means.
Best–
MRE
So you took down my post? As a neurologist, I was hoping you would have commented in case I was the wrong who was wrong since the wording in the article, I agree, was not clear. Apparently, I wasn’t.
As Taubes would say, a true scientist is one who can admit mistakes and look objectively at the data.
Best luck in your business venture.
Hey Joe–
I didn’t take down your post. I’m working my way down the 100 or so comments requiring comment from me and simply haven’t gotten to yours yet.
Cheers–
MRE
Based on my own experience, the weight loss on a low carb diet has little to do with calories. After a particularly stressful time with a sick child, I gained 10 lbs. Over a period of 2 years I tried to get rid of it. I gradually removed calories and added exercise classes. I got to the point where I was exercising 5 – 15 times a week and eating an average of 800 calories a day. I could not lose the weight I had gained. At first I thought I was losing my mind, since it was not possible to break the laws of physics. After 2 years of this a friend told me to try the Atkins diet. Eating 1000 calories/day, in 1 month I lost 20 pounds. I had to start adding calories because I was losing weight too fast. At 2500-3000 cal/day my weight stabilized. I mentioned it to my doctor and he showed me ‘scientific’ studies that ‘proved’ I was risking my life and scared me into going back to my low calorie diet. Within 2 months, on 1000 calories, the weight was back.
Last Fall I tuned into a CNN program with Gary Taubes and he blew the other guests out of the water. So, I decided to get his book. I am not a scientist, but after reading the book the evidence is so clear, to repudiate it seems criminal. Now, I am back on low-carb to stay because now I understand why it worked. But who is looking out for all of those children who are being led down the low calorie/ low fat road?
Is the study of diet for diabetics that the NIH just discontinued because it was deemed possibly harmful when they found that people were dying, the same study that Taubes cites in the last few pages of the book? And what do you think are the implications of this action by NIH?
I’m fascinated by this book. It’s taken me literally MONTHS to read because I don’t have a scientific mind and I didn’t want to just breeze past the studies…but I am finally finished with it and FINALLY feel vindicated. I’m now retraining myself NOT to think of myself as lacking character because I was nearly 300 lbs at one time.
I know that the only thing that saved me was changing my eating habits to low-carb (Thanks to the Eades…it was their Protein Power book that got me started in 1999 and even with ups and downs over the years I’m nearly where I want to be!) It hasn’t helped to have a sister who has rarely topped 100 lbs in her life…especially with her comments like “Why can’t you just eat everything in moderation???” “Just have a little of everything” all while she served me rice centered meals (her husband is Iranian and well, rice is definitely one of their mainstays). It didn’t matter that I tried to explain over and over and over again that if I have a little, I’ll be eating, or ather gorging, myself on sugary, carb-laden food for weeks afterwards, as I struggle to once again work them out of my diet. It was good to know that it is a physiological problem not psychological, or at least not MORAL!
I want to thank Gary for the work he put into this book and the Eades, who set me on this path to a thinner, healthier me! (The healthier is documented in low cholesterol, low blood pressure, low-normal blood sugar levels.)
Thank you!
Hi Keren–
Congratulations on your success. I know it’s been a long, hard struggle because weight loss is not easy under any circumstances. You’ve really accomplished something quite amazing.
The study the NIH just stopped isn’t the one Gary was talking about. I’m going to post on the NIH study next.
And I’m going to pass your comment along to Gary so that he can see that his book is having an impact on individual lives.
Thanks for writing.
Best–
MRE
I will add just because I can…I leave March 1st for Costa Rica to have surgery to remove all the excess skin remaining from my weight loss. I want to finally look outside like I feel inside. Seriously, you doctors may never have heard my name before now but you’ve been a major part of my life for the past 8 years (or is it 10?) and I am so thankful for the light you’ve been. Mr. Taubes book is just the icing on the cake, I guess…or rather, the butter sauce on my pork chop!
Good luck with the surgery. And thanks for the kind words. You’re the one who really did all the hard work.
Cheers–
MRE
I started the low carb lifestyle back in 1999, just like some others on this post. I lost 60 pounds in one year, and I’ve kept it off by maintaining the lifestyle. Thank you, Dr. Eades – I read Protein Power after getting the book from my mother, who I barely recognized after she lost 40 pounds in only a few months.
I frequently get into heated debates, often with physicians, and very few of them understand the biochemistry of fat metabolism. After reading Gary’s book, I feel more empowered than ever. He did a tremendous job of criticizing the conventional wisdom (or lack thereof) about diet and nutrition.
I teach high school biology, and I’ve been incorporating the concepts of low carb dieting to my students. I am frequently criticized by my colleagues, particulary the physical education department and nursing staff, for teaching something so “controversial.” When I explain the concepts to them, the faces looking back at me say “I think I understand what you’re trying to say, but I don’t believe you.” Fortunately, my students are better learners than the adult community. My next attempt to “spread the word” will be to establish a “wellness link” on my school’s website, where I will give free advice for anyone who wants it. I am not trying to promote anything except good health.
Thanks again, Dr. Eades!
Hey Mike–
Good for you! Keep fighting the good fight. It constantly amazes me how much nutritional ignorance abounds – even in places where it shouldn’t. We’ve got to keep getting the message out.
Best–
MRE