The news of "fat and thin" all come from the simplest formula: 0.5 kg of body weight = 3500 calories. The great joys and sorrows of weight loss are all the result of the body's precise calculations. If we consume 3500 calories less, our body will extract the same amount of heat from fat, and our weight will decrease by 0.5 kg. Eating more but becoming thinner is no longer a privilege of a few people.