A simple observation of the eating habits of my (skinny) husband and (not at all skinny) me will reveal two things: DH can eat whatever he wants and not gain weight, and DH can eat whatever he wants, and his blood sugar will be perfect an hour a later. Neither of these things is true for me. So I was very pleased to read Gary Taubes' convincing, eloquent explanation of how these two things are linked.
I was diagnosed with gestational diabetes with my first pregnancy; I wasn't with the last two, but I still tested my blood sugar pretty regularly to make sure things were staying under control. As a result, I'm a lot more intimately familiar with my blood sugar than most non-diabetics. When I was diagnosed with GD 10 years ago, pretty much the only advice the nutritionist I met with gave me was to count carbs. And in my adventures with my blood sugar monitor it wasn't hard to see a relationship between eating carbs and my blood sugar levels: too many carbs of any type or pretty much any amount of pure simple carbs (i.e. fruit juice or coke) shot my levels up dramatically. So when I first started listening to Gary Taubes, I thought maybe he was exaggerating the "other side's" position for dramatic effect. Surely everyone recognizes that too many carbs are bad at the very least for a certain (large and rapidly growing) segment of the population that's especially sensitive to them, right? Then I started looking around, and realized that, in fact, there are people out there who say that diabetics need to cut their fat and that, other than pure sugar, they don't need to really worry about carbs. Fruit is fine, one site said, but if it makes you feel better you can cut down on it. Again, this is so counter my own experience with drinking 1/4 cup of orange juice when I was pregnant, that it seemed absurd. This might explain, though, why my mother, who's been a diabetic for 10 years, eats a peanut butter and jelly sandwich almost every night for dinner. No one's ever told her she shouldn't.
I almost didn't read WWGF because I was already pretty well convinced that, at least for me, a low or moderate carb diet was what I ought to be doing. Then I actually started doing it, and that made me a little more interested in the science behind the whole thing. Taubes thesis is that obesity is the result of a hormonal disorder involving insulin regulation, and that overeating and sedentary behavior is not the cause of obesity but a side effect of it. It's very clear to me, again, from my own experiences, that eating a big dose of carbohydrates (particularly if unaccompanied by sufficient protein and fat) leads to a blood sugar crash a couple of hours later that makes me crave sugar like crazy (sugar being the fastest way to restore my blood sugar to a reasonable level). So it makes complete sense to me that the same thing might be happening, on a less dramatic level, with lower levels of carbohydrate eating. It's also very clear after just a few days on a lowish carb diet that eating fewer carbs is remarkably effective for getting rid of sugar cravings. I won't get into the science of it more than that, because I suck at explaining science-y things. WWGF is presented in the introduction as sort of Good Calories, Bad Calories (Taubes' earlier, much longer, book on the same topic) for Dummies. "People kept asking me for a version that they could share with their not very bright cousin Ed," says Taubes (okay; not in so many words). This was enough for me. I don't feel a need to read Good Calories, Bad Calories.
I am much more schooled in analyzing writing than in analyzing science, however, so I'll blather on for a bit about that. First off, let me say that I believe Taubes is entirely sincere. At one point he says he's willing to stake his reputation on his claims, and, in fact, he has. He's clearly a serious guy--an award winning science journalist--and I don't think he would be pushing so hard a view many still see as quackery if he weren't certain about it. But, as John Kerry once told George W. Bush, "you can be certain, and you can be wrong." And once you're certain, all the evidence can seem to support what you already believe to be true. Taubes himself admits as much; this, he says, is why the high carb/low fat thinking has prevailed for so long in the face of all contrary evidence, and this, he admits, is a phenomenon that he is subject to as well. Taubes is also nothing if not long-winded. And he's a bright guy and a good writer, which makes me read (listen) extra carefully, lest I fall prey to the smartest guy in the room syndrome. All of that said, I find Taubes pretty damn convincing. He throws study after study at you and tosses in a lot of historical information; there's prettty much nothing in the way of personal anecdotes, and he's not fond of sensationalism or hyperbole (his relentless use of the phrase "fattening carbohydrates" in a transparent attempt to change conventional wisdom by changing language gets a little annoying).
I read a lot of anti-Taubes stuff as well while I was listening to the book. Most Taubes criticism seems to fall into two categories: 1. people who parrot back the opinions of "experts" who disagree with Taubes and then announce triumphantly: "see! he's wrong!" Since Taubes' entire point is that the experts have gotten things wrong for the past 50 years, this line of criticism is a bit...misguided. 2. people who clearly haven't read the book and throw out gotcha, "but what about.....!" statements. Like, "what about in Asia?! With all the rice!" Turns out if you read the book, even the for Dummies version, there's not much that Taubes hasn't considered and addressed...including what about Asia with all the rice (I got a little distracted during that part, but it has something to do with how traditional Asian diets don't include many simple carbohydrates, so they haven't destroyed their bodies, and they can still eat rice...except for in the places where they have McDonald's and sugar now; those people are all getting diabetes. Also, Taubes never claims that no one can eat carbohydrates without getting fat. His analogy is this: not everyone who smokes cigarettes will get lung cancer, but most of the people who get lung cancer get it because they smoked).
But some of the criticism is thoughtful and deserves attention. I read one critique (not of this book, but of Taubes' 2002?(ish) piece in the NYT magazine that started to lay out some of these ideas) in Reason magazine, that seemed to raise some good points (except that that guy poo pooed the idea that eating carbs can set up a blood sugar crash that makes you crave carbs...and, as I've mentioned, that's something I experience regularly (and I don't think it's particularly uncommon)). Then I read Taubes' rebuttal, which addressed absolutely every critique the guy made and ran something like twice as long as the original critique. Again....does this mean he's right or just that he'll talk longer than anyone else? The most reasonable sounding critiques of Taubes are generally from people who have no particular agenda and who say things like, "Taubes makes some good points about x and y, but I disagree with him here." Michael Pollan seems to be one of these people (and the respect mingled with healthy skepticism seems mutual; both authors quote the other frequently, but sometimes have quibbles). A lot of people raise good questions about his POV on exercise (namely, that it's largely unhelpful for sustained weight loss). It's worth noting that there's plenty of overlap between Taubes' view and conventional wisdom these days, too. Taubes regularly stresses that refined carbohydrates, especially in liquid form, are the worst offenders, and that for a lot of people cutting these out may be all that's needed. Although Taubes pulls up some pretty outrageous quotes from nutrition experts in the 80's, at the height of the low fat craze, there's not really anyone TODAY who suggests that you're better off drinking Coke than eating eggs (I don't think there is, anyway).
I wondered if perhaps Taubes was cherry-picking studies (as he's been accused of) when he extols the amazing results of low carb diets, so I checked out the Wikipedia article on the studies that have been done. I expected them to be somewhat inconclusive; the impression I've gotten from the media over the years is that some studies show low fat diets as better than low carb, and some show the opposite. I was surprised to learn that, assuming Wikipedia hasn't fallen prey to a low carb conspiracy, the results of recent research is pretty uniformly positive for low carb diets. Weight loss is generally better than on low fat or straight up calorie restricted diets--at worst it's roughly the same (and with, remember, no calorie restrictions), and heart health indicators almost always get better on low carb diets.
For me personally, if I had to name my own quibbles/questions about the book (which, to be clear, I am, by and large, a huge fan of)....I'd echo the questions about exercise. It's true that I don't find exercise particularly helpful with weight loss now, in my mid-thirties, but it definitely made a difference 10 or 15 years ago, when I could eat complete crap all the time (including copious amounts of liquid sugar) and stay pretty thin as long as I jogged 20 or 30 minutes a day. Taubes tends to talk mostly about "exercise" as if all of it is the same, without making any distinctions about type, duration, who's doing it, etc. And, perhaps this falls under the category of criticizing the book the author didn't write, but Taubes himself brings up, briefly, in the introduction, the ethical considerations in adopting a diet composed largely of animal products. But then he never really addresses it. Unlike Pollan, he makes no argument, ethical or nutritional, for eating pastured meat and dairy. I do eat mostly pastured meat and eggs (dairy is a work in progress), but I recognize that this is a luxury, and I'm not sure there's any question that the world's carrying capacity is a lot higher when we mostly eat plants. But, again, that's a different book.
Ultimately, while Taubes himself is entirely convinced of his "alternate hypothesis" (as he calls it) he recognizes and emphasizes that that's what it is. His purpose here is partially to convince people that he's right, but also to convince the scientific community that more good research is needed...because if he is right then time's a-wasting.
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