The Obesity Code: Unlocking the Secrets of Weight Loss (Why Intermittent Fasting Is the Key to Controlling Your Weight)

by Jason Fung

There is no survival advantage to carrying a very high body-fat percentage. A male marathon runner may have 5 percent to 11 percent body fat. This amount provides enough energy to survive for more than a month without eating. Certain animals fatten regularly. For instance, bears routinely gain weight before hibernation—and they do so without illness. Humans, though, do not hibernate. There is an important difference between being fat and being obese. Obesity is the state of being fat to the point of having detrimental health consequences. Bears, along with whales, walruses and other fat animals are fat, but not obese, since they suffer no health consequences. They are, in fact, genetically programmed to become fat. We aren’t. In humans, evolution did not favor obesity, but rather, leanness.