The answer is: it is best not to! Dieting without exercise can reduce weight. However, it is easy for you to enter the painful state of repeated weight fluctuations, which is technically called "periodic weight" or "yo-yo effect". An associate professor of psychology at UCLA conducted a one-year follow-up survey of people who went on a diet to lose weight. Finally, it is found that people who only diet and do not exercise have a weight rebound rate as high as 4 1%. Cyclic weight refers to the repeated decrease and increase of weight. Usually, periodic weight is the result of dieting to lose weight. The weight of a cycle may fluctuate only within a small range (5 to 10 kg), but it may also fluctuate greatly (above 50 kg). The typical process of periodic weighting is as follows: 1. You start dieting, but don't exercise. Therefore, your body's metabolic rate will slow down. After losing weight, you will soon stop dieting. Now, you eat as much as before, even more. As a result, you gained weight again. 4. The desire to lose weight failed, so you started dieting again. This cycle ... when we go on a diet, the body still needs a certain amount of "fuel" to run. If we don't get calories from food, then our body will break down its stored fat and muscle tissue to get energy. Moreover, it breaks down muscle tissue much faster than fat. At this time, you lost weight, but not necessarily. After stopping dieting, the body recovered a lot of calories, but it could not effectively decompose the excess calories, and then the weight rebounded. Therefore, a diet plan that does not include exercise can easily lead to periodic weight loss and it is difficult to maintain weight.