If you eat sugar you become fat. If you eat fat, you lose weight.
Of course, in practice things aren’t quite as simple as this. You have to eat the right kind of fat, in the right quantity and at the right times. It also makes all the difference what else you are putting into your body. The quickest way to become enormous, for example, is to consume high quantities of both fat and carbohydrate, as found in the worst and hardest to resist doughnut. But the basic message remains true. It isn’t fat that’s responsible for the epidemic of obesity sweeping the planet. It’s sugar!
Intuitively, it sounds crazy to suggest that the way to lose body fat is to eat more fat than you are already doing. But remember, biology is not simple mathematics or physics. Our bodies break down what we eat and turn it into other things, including energy.