Most of us have dieted to lose weight, only to gain it back again within a few weeks or months. It isn’t that diets don’t work. It’s that they don’t last. Most diets are so unpleasant, inconvenient, boring, complex, or expensive that they are difficult to stick with for very long. When you quit the diet, the weight returns.

Think of excess fat as a collection of calorie-adding habits. Lose the habits and you will lose the fat. Each time you give up one of these habits (all other things being e...