Why We Get Fat, and What To do About It
I have been waiting for a book written from this angle for years. The "standard" theory of weight management is so simplistic it isn't of much help. Sure, people gain weight because they eat more than they burn, duh. Why does this imbalance exist? Why does it happen to some people and not others? Why is obesity on the rise? Why is it so hard to fix?
Saying that people are more slothful and gluttonous nowadays, while common, does not seem to be a reasonable answer, not when the weight gain is happening so fast, is so widespread, and occurring even to infants.
Gary Taubes has been pursuing the answers to these questions for a while. First, he presents evidence that the calories-in/calories-out model is fundamentally flawed. In animals, including humans, it appears that bodies set an internal standard for how much fat should be maintained and where it goes. Attempts to influence this value through changing caloric intake or activity might be temporarily successful, but they won't last. Gary presents ample evidence from history, scientific research, and population studies to prove his point.
So what's the cause of obesity, then? In some people it may just be genetic. Overall, though it looks like carbohydrates and sugar are the culprits. The author explains the effect that carbohydrate intake has on blood insulin levels, and the effect insulin has on fat stores. None of this biochemistry is debated at all, but there seems to be a glaring disconnect between the science of hormone signaling and theories of diet and weight loss.
To further prove his point, Gary next analyzes various diets and how successful they have been. In the end, it seems that a low carbohydrate diet is the best choice for weight loss, diabetes/insulin resistance, and overall health, *but* he warns, it hasn't been exhaustively tested long term yet. Initial tests are very promising though, showing improved blood lipids, and the most significant weight loss. A quick sample diet is provided in the appendix.
This is not a diet or weight loss book. This is an inquiry into why people get fat, starting without preconceived notions. As such, I think it's extremely valuable. This is a crucial subject, and the current set of theories and advice do not seem to be helping people much.
Which is not to say that I agreed 100% with the author. He has his theory and he pursues it fully, with the best evidence he can find. That's fine, but I noticed a few gaps. For one, just because the body has an idea how big its ideal fat stores should be, doesn't mean that people can't essentially force-feed themselves by eating beyond what hunger would dictate. Restaurant portions and addictive snacks are likely culprits in obesity too. See The End of Overeating: Taking Control of the Insatiable American Appetite for information on that.
Exercise, too, is dismissed as useless for weight loss. I agree that it's not effective for mere calorie burning. Appetite will counteract any deficit achieved. But exercise, especially long or high-intensity aerobic exercise uses up carbohydrates. And thus, by his theory regular aerobic exercise should have a similar effect to eating a low-carbohydrate diet. (I have read studies where this appears to be the case.)
Still, I think this is a fabulous book despite the occasional blind spot. If you are interested in the biology behind weight regulation, this is a must read.
[Originally posted to Amazon.com]