It is true that gaining weight results from taking in more calories than you expend. But excess
calories certainly cause you to pile on the pounds-and this is a gigantic "but"-only when you are
eating a lot of carbohydrate along with fat.
So it's time to abandon the assumption that the only way to lose weight is to strictly control
your intake of calories. Many people think that only one thing matters: how many calories you
take in and use up. It's not that simple.
When you follow a controlled carbohydrate approach, you get what I call a "metabolic
advantage. When you control carbohydrate consumption sufficiently, your body will switch from
burning glucose derived from carbohydrate to burning primarily fat for energy. This means you
could eat, say, 2,000 calories and still begin losing pounds and inches.
In contrast, if you were consuming 2,000 calories on a low-fat diet, you might not lose weight,
and you might actually gain weight. The metabolic advantage is that burning fat takes more
energy so you expend more calories. And if you eat fewer calories-as many Atkins people do
because their appetite is usually diminished-you'll likely lose weight even faster. So it's not that
calories don't count, it's just that you will burn more of them, with less hunger, when your body
is operating on a fat-based metabolism.
When I published the first edition of this book ten years ago, that claim was quite
controversial. Today it is galloping into acceptance among scientists who study the human
metabolism. Glance through the references listed at the back of this book and you will see the
numerous studies and articles published in the past six years. And, we will deal with the
metabolic advantage in greater detail in Chapter 7