Over my holiday break, I read an excellent new book on weight loss titled The Smarter Science of Slim. Jonathan Bailor, the author, has (according to the preface) been researching the science of weight gain and weight loss for 10 years, and it shows: the index of references at the back of the book runs more than 70 pages. Despite immersing himself in heavy-duty nutrition science while writing this book, Bailor had the good sense to explain what he’s learned clearly and simply. In other words, the book passes my “Aunt Martha” test.
In a nutshell, the book’s message comes down to this: Most of us will never lose weight and keep it off by simply restricting calories. Permanent weight loss requires changing your body’s set-point, and your body’s set-point is largely determined by hormones. To shed body fat, we need to clear what Bailor terms a hormonal clog in the fat-metabolism system. Clearing the clog is, of course, a matter of choosing the right foods and the right kind of exercise, not just eating less and moving around more.
I believe we can’t emphasize that point often enough. Yes, you can starve yourself and lose weight. But losing weight without changing your set-point – the amount of fat your body wants to maintain – is a bit like pulling a big ol’ rubber band into a stretched position and trying to hold it there forever. Sooner or later, you’re going to tire of the effort and let go … and then that rubber band will snap back to its original size. That’s why most low-calorie diets fail over time. It’s why so many contestants from The Biggest Loser have regained the weight they lost. (Many have also ended up with depressed metabolisms for their efforts.)
Early in the book, Bailor takes on the calories-in/calories-out view of fat loss and shreds it with data from several studies. In one study, for example, researchers had thin people and fat people stop eating completely -– call it a zero-calorie diet. Then the researchers determined what the subjects’ bodies burned for energy. The results were, as Bailor notes, depressing: The thin subjects obtained 61% of their calories from stored body fat, while the fat people only obtained 39% of their calories from stored body fat. Worse, they burned up more of their own muscle mass than the thin people. Lose muscle, and all you’re doing is slowing your metabolism. As Bailor writes:
Think about that for a second. Despite having more body fat, the heavy people burned less body fat. In the words of the researchers, “… obese patients could not take advantage of their more abundant fat fuel sources.” The heavy people burned what relatively little muscle tissue they had rather than burning the excess body fat they were drowning in. They needed to burn body fat, but did not burn body fat effectively. This is where the idea of a clog comes into play.
In a subsequent chapter, Bailor reviews the scientific literature on exercising more to lose weight. You can probably guess what he found: In study after study, exercise has failed to produce more than a few pounds of weight loss … not exactly the result an obese person hopes to achieve.
The key to lasting weight loss, Bailor writes, is to focus on consuming SANE foods. SANE is his acronym for the qualities of a food that affect weight gain:
- Satiety – how quickly calories fill us up and how long they keep us full
- Aggression – how likely calories are to be stored as body fat
- Nutrition – how many nutrients (protein, vitamins, minerals, essentially fatty acids, etc.) the calories provide
- Efficiency – how many calories can be stored as body fat
As he explains:
The more Satisfying, unAggressive, Nutritious and inEfficient a calorie is, the higher its quality. The more SANE it is. The more body-fat burning hormones it triggers. The more it clears our clog and prevents overeating. The more it restores our ability to burn body fat and maximizes our need to burn body fat.
The more unSatisfying, Aggressive, not Nutritious and Efficient a calorie is, the lower its quality. The more inSANE it is. The more body-fat-storing hormones it triggers. The more it creates a clog and encourages overeating. The more it destroys our ability to burn body fat and removes our need to burn body fat.
The next four chapters explain each of these four factors in detail. You won’t be surprised to learn that the most inSANE foods are sugars and refined starches, while the most SANE foods are non-starchy vegetables, meats, eggs, seafood and some dairy products.
High-protein foods are a perfect example of SANE foods. Research has shown that protein is satiating –- we eat partly to satisfy our daily protein requirements, so if we’re eating low-protein foods, our bodies tell us to keep eating. Protein is also the macronutrient least likely to be converted to stored body fat. Bailor takes the reader through a brief bit of biochemistry in one chapter to demonstrate that if we consume 300 calories of protein, at most 105 of those calories can be converted to fat. The rest is lost in the conversion process. In other words, protein is low on the Efficiency scale.
By contrast, 211 calories from 300 calories of refined starch can potentially end up as body fat. Starch is twice as high on the Efficiency scale as protein, and also high on the Aggression scale because it triggers high blood sugar and high insulin levels that encourage our bodies to store fat. I was pleased to see that there’s an entire chapter in The Smarter Science of Slim on how insulin and other hormones affect weight gain, all explained pretty simply.
In other chapters, Bailor reviews how our hunter-gatherer ancestors ate, where today’s lousy standard dietary advice came from, why the “cholesterol kills!” theory is full of bologna, and how starchy/sweet foods ended up becoming our dietary staples. Then he moves on to how we can eat smarter and lose weight without starving ourselves.
Given his SANE scale, it’s no surprise that the diet he recommends is pretty close to a paleo diet: lots of vegetables, plenty of protein, a bit of low-sugar fruit, some nuts now and then, and perhaps a few dairy products.
Where he separates himself from the low-carb crowd is in the proportions of protein, fats and carbohydrates he recommends. While he does a nice job of debunking the theory that saturated fat and cholesterol are bad for us, his SANE diet still limits dietary fat in favor of extra protein and carbohydrates (compared to most low-carb diet plans, that is) as a means of promoting weight loss. Consequently, he suggests consuming egg whites and low-fat dairy products instead of the full-fat varieties. He also recommends getting about a third of our calories from carbohydrates, with the caveat that we get those carbohydrates from SANE fruits and vegetables instead of sugars and refined starches.
While I believe the diet he recommends is a good one — far better than what most people consume — I’m not convinced that a ratio of one-third fat, one-third protein and one-third SANE carbohydrates is necessary to lose weight. It certainly hasn’t been the case for me. Bailor has agreed to do a written interview for a post next week, so I’ll ask him to explain why he recommends those specific proportions.
The last section of the book is dedicated to exercise. Even though Bailor describes early in the book why most exercise does little for weight loss, he’s certainly not opposed to exercise … he just wants us to engage in exercise that actually helps. The key is to work our muscles briefly but intensely, then give them adequate time to recover. In that regard, what he recommends is a lot like Fred Hahn’s Slow Burn program. The main difference is that Bailor favors working the muscles with negative resistance … that is, exercising the muscles to the point of failure while lowering heavy weights instead of while lifting them. (Tim Ferriss makes the same recommendation in The 4-Hour Body, at least as an alternate workout.)
Once again, Bailor describes the crucial role hormones play in our body composition. In one surprising (to me, anway) study he recounts, researchers divided subjects into two groups: the first group exercised only one arm, while the second group exercised the same arm, but also both legs. At the end of the trial, researchers measured how much the subjects had increased their arm strength. The result: the subjects who exercised just one arm were 9% stronger on average in that arm. But the group that also exercised both legs were 37% stronger on average – in the arm! The reason? Hormones. As Bailor writes:
Leg-training worked more muscle and therefore triggered more whole-body-transforming hormones than arm training. All those whole-body-transforming hormones benefit seemingly unrelated muscles more than exercising those muscles directly.
Body composition is largely determined by hormones. What we choose to eat –- not how much — and how we choose to exercise – now how often or for how long — has a huge impact on the hormones our bodies produce. That’s the message of The Smarter Science of Slim. It’s a message people struggling to lose weight and get fit need to hear.
I have a list of questions for my upcoming interview with Jonathan Bailor, but feel free to post your own in the comments. I’ll pick a few to add to my list.