It's hard to lose 20 in half a month. It really depends on your weight. Unless you are fat and your body is mostly fat, it is possible. I have tried many ways to lose weight. The shortest time and the most effective are two. One is acupuncture (I only did one course of treatment and lost 22 pounds in a month or so), which lasted for two years. Usually pay attention to diet, there is no rebound. Not bad. It's expensive. The second is to take medicine, which I am taking now. I gained a lot of weight because I was sick before. Almost 140 kg, which belongs to muscular obesity. So I'm taking medicine now, (I've lost weight about a month 16 kg), but I'll feel dizzy and insomnia in the first two or three days. Not since. The dosage of that medicine is two bottles a month, but I was afraid I would feel uncomfortable at first, so I reduced it by half, and the effect was still very satisfactory. Besides, I am a person who doesn't like sports. I can see all the methods I use to lose weight, so I don't exercise either. It is not easy to reduce this. A friend of mine is also eating. She weighs about 120 kg. After eating for a month, she lost more than 7 kilograms. When I take this medicine, I'm just not hungry and don't want to eat. Just drink more water. But my friend, she can't. She can still eat and eat according to her usual amount. But there are also thin ones. I think it depends on a person's physique. Exercise has no effect on me. Before taking this medicine, I just wanted to diet and exercise to lose weight, so I went running. It will also be healthier. But I ran for a week and went on a diet. But instead of losing weight, I gained more than 5 Jin. So I gave up sports. I hope you can also find a way to lose weight that suits you. Can succeed.