"Everybody “knows” that people who are overweight overeat. Doctors know it. Diet writers know it. The lecturers at Weight Watchers know it. Everybody knows it. And so, if you are overweight, you probably know it, too. But when I approached the problem mathematically, the numbers didn’t know it. And the numbers were clear. Boy, have we been wrong….I computed that each pound of body fat is maintained by less than one extra calorie per hour."