I've been rereading Gary Taubes' new book, and there are some really good sections in it. I think his best thinking might come on the subject of energy intake and energy expenditure.
Normally, if a person is overweight, it is thought that they have become this way because their energy intake has surpassed their energy expenditure. This is true, but Taubes goes further to ask, why? And why does this happen in some people and not others, and why does it start happening to cultures at certain time periods.
Taubes' theory is that carbohydrate (or refined carbohydrate) alters the hormonal landscape which in fact leads to less energy expenditure and more energy intake; in other words, a person eats more calories and becomes less active.
Taking this line of thought further, Taubes thinks that the typical advice for a person trying to lose weight, eat less and exercise more, is fundamentally flawed. Instead, he thinks that if the dietary component causing all the problems (carbohydrate) is removed, then calories consumed goes down and activity goes up, which will eventually cause the weight to balance out.
To me, this theory makes perfect sense. I have seen countless studies where calories are restricted, and in the short term they lose weight. But then as the body compensates (metabolism and activity slow), the weight comes right back. These studies don't get at the essence of the problem: it is they type of food being consumed, not the calories per se, that is causing a person to become overweight.
Here's another way to think of it: body fat is thought of as energy storage, "extra" calories that are tucked away and can be used later. So following this logic, a person who is very overweight should have tons of energy available and be very energetic. But generally, that isn't the case. Taubes believes that an overweight person can't access their fat stores for the same reason the calories turned to fat in the first place: the presence of carbohydrates in the diet.
However, I don't believe Taubes accurately analyzes carbohydrates as I will discuss in the next post.
