Okay, so you tried to get your Aunt Martha to read Good Calories, Bad Calories before she joined Weight Watchers for the 13th time, but she handed it back after two weeks and said she couldn’t get through it. That’s no knock on Aunt Martha. GCBC is a ground-breaking book, but heavy on science and therefore not an easy read. I remember reading some sections three times before I felt I’d fully grasped them.
A lot of us who did enjoy the book were nonetheless hoping Gary Taubes would write a follow-up that would essentially be Good Calories, Bad Calories Lite: reads great, less taxing. Apparently Taubes had the same idea, because eventually he announced he was working on a consumer-level book that would focus mostly on weight gain and loss — which, like it or not, is probably the topic that most motivates people to read up on nutrition. (Cancer? Yeah, yeah. Diabetes? Whatever. Just tell me how to get rid of all this flab, already!)
The new book, Why We Get Fat And What to Do About It, was in the box of mail waiting for us when we returned from Christmas vacation, and I read the whole thing in a couple of weekend afternoons. That is, of course, exactly what I was hoping for: a book I can recommend to people who want to learn some of the science behind weight loss, but whose eyes glaze over if you hand them a 500-page heavyweight.
Why We Get Fat is just over 200 pages. But reading 200 pages of this book isn’t like reading 200 pages of Good Calories, Bad Calories. A lot of the same science is there, but Taubes went to great lengths to explain it as simply as possible. He uses more examples and analogies than in GCBC, and the writing style is less academic and more conversational. Here’s a sample paragraph:
The correct way to think about fat tissue is that it’s more like a wallet than a savings or retirement account. You’re always putting fat into it, and you’re always taking fat out. You get a tiny bit fatter (more fat goes into our fat cells than comes out) during and after every meal, and then you get a tiny bit leaner again (the opposite occurs) after the meal is digested. And you get leaner still while sleeping.
Even when it’s necessary to delve into a bit of biochemistry to explain a concept, the language is simple and direct:
The fact that fat is flowing into and out of our fat cells all day long, though, doesn’t explain how the cells decide what fat gets to come and go, and what fat has no choice and is locked away inside. This decision is made very simply, based on the form of the fat. The fat in our bodies exists in two different forms that serve entirely different purposes. Fat flows in and out of cells in the form of molecules called “fatty acids”; this is also the form we burn for fuel. We store fat in the form of molecules called “triglycerides,” which are composed of three fatty acids (“tri-”) bound together by a molecule of glycerol (“glyceride”).
The reason for this role distribution is again surprisingly simple: triglycerides are too big to flow through the membranes that surround every cell, whereas fatty acids are small enough to slip through cell membranes with relative ease, and so they do. Flowing back and forth, in and out of fat cells all day long, they can be burned for fuel whenever needed. Triglycerides are the form in which fat is fixed inside fat cells, stashed away for future use. For this reason, the triglycerides first have to be constructed inside a fat cell (the technical term is “esterification”) from their component fatty acids, which is what happens.
There’s even a drawing accompanying that paragraph to clarify the process further.
Since the book focuses on weight gain and loss, many of the topics covered in Good Calories, Bad Calories — cancer, dietary fiber, Ancel Keys, the McGovern committee, Alzheimer’s, diabetes — either don’t make an appearance or are discussed only briefly. Taubes does cover the Lipid Hypothesis, but mostly for the sake of assuring readers it isn’t supported by the scientific evidence, which means we can swap fat for carbohydrates in our diets without inducing heart disease.
After the introduction, Why We Get Fat explains what didn’t make us fat: prosperity leading to gluttony and sloth. Obesity has been common among populations who were poor beyond our imaginations, even among those who worked long hours at manual-labor jobs. The scientific research shows that exercise may be good for our overall health, but does little to help us shed excess body fat. And of course, low-calorie diets have an abysmal track record — even the obesity “experts” who promote them admit as much in private. In other words, after 200 years of our existence as a nation we didn’t — in one generation, mind you — become fatter because we decided that since we’re well-off now, we should start eating too much and moving too little.
For those who never bothered to read Good Calories, Bad Calories and believe Taubes failed to consider the laws of physics when writing it (which would be pretty strange, since he has a degree in physics and a master’s in aerospace engineering), there’s a section titled Thermodynamics For Dummies, broken into two chapters. Considering that he’s been lectured on the laws of thermodynamics by jocks with certificates as “personal trainers,” I’m guessing he smiled when he named those chapters. There’s nothing in the hypothesis he presented in Good Calories, Bad Calories (or in this book) that would require energy to magically disappear. I’ll write about that in an upcoming post.
From there, Taubes moves on to explain what he calls the alternative hypothesis: hormones tell our bodies to store more fat, and our bodies listen, whether we like it or not. Most of what he covers here was included in Good Calories, Bad Calories, but now it’s presented in an easy-to-understand section titled Adiposity 101, which makes up the majority of the book. You already know the basics — the wrong quantity or quality of carbohydrates drives up insulin, which drives fat storage — so I won’t go into detail here. For the details, buy the book.
I was pleased to discover a fair amount of new information in Why We Get Fat as well. Taubes includes some recent studies, and writes quite a bit more about the biological effects of consuming too much fructose. He also takes a bit of a paleo perspective in one chapter, discussing what we can learn from the diets of the 229 hunter-gatherer societies anthropologists were able to examine before civilization moved in. (Bottom line: heavy on meats and organ foods, and the fattier, the better.)
I was also pleased to see that throughout the book, Taubes pounds home a message that needs to find its way into the brains of public-health activists, doctors, and government busybodies: Obesity isn’t about character. It’s about biochemistry. We aren’t going turn fat people into thin people by shaming them, shoving calorie counts in their faces, or building more bike paths near their homes.
Most obese people hate being fat and have tried many times to lose weight. As Taubes points out, if shedding excess body fat were really as simple as cutting 100 calories per day, pretty much every fat person would do it. The trouble is, most of them have done it, only to find it didn’t work. Meanwhile, people who’ve never been fat and regularly eat until they’re full expect obese people to spend the rest of lives feeling half-starved so they can become lean.
But of course, the message of Why We Get Fat is that we don’t have to spend our lives feeling starved or horsewhip ourselves into jogging every day to fix the biochemical imbalances that make us fat:
We’ve been told for so long, and believed for so long, that a fundamental requirement for weight loss is to eat less than we’d like, and for weight maintenance that we eat in moderation, that it’s natural to assume the same is true when we restrict carbohydrates …
It’s true that people who restrict carbohydrates often eat less than they otherwise might. A common experience is to give up fattening carbohydrates and find that you’re not as hungry as you used to be, that mid-morning snacks are no longer necessary. But that’s because you’re now burning your fat stores for fuel, which you didn’t do before. Your fat cells are now working properly as short-term energy buffers, not long-term lockups for the calories they’ve sequestered.
Note to the celebrity personal-trainers who never got around to tackling the chapter in Good Calories, Bad Calories about energy balance and thermodynamics: read the paragraph above again. Nothing in it says calories magically disappear on a low-carb diet.
Although Why We Get Fat is mostly a consumer-level look at the science of weight gain and loss and not a diet book per se, the appendix does spell out a low-carb diet that was originally designed by the Lifestyle Medicine Clinic at Duke University. It so happens that clinic is run by Dr. Eric Westman, one of the three doctors who wrote the latest Atkins diet book.
So in fact, you could read this book to understand why you may need to change your diet, then refer to the appendix for ideas on how to implement those changes (although I still think you’ll want to pick up a good low-carb cookbook). But just as importantly, this is the book you can give to people who want to understand the science of why you’re finally losing weight … without being hungry and miserable doing it.