Do you only need to focus on calorie consumption and intake to lose weight? Do you only need to focus on the ratio of muscle to fat when losing weight? Is the ketogenic diet all you need to lose weight? Light fasting? Vegetable juice? Low carb? ... Any weight loss method that doesn't talk about "fixed weight" is just a hooligan! If you: gain weight after drinking cold water, and gain weight when you look at the cake. If you: continue to overwork, the more tired you are, the hungrier you are. The more hungry you are, the more you eat, and the more you eat, the more tired you are. If you: diet for a long time to lose weight, it never works. If you: used to be a weight loss drug taster, a lover of processed food, and have repeatedly failed on the road of self-struggle... The fault is not yours. Please use the guidance of this book to get back on the right path. 1. The author is a bariatric surgeon with extensive medical practice. His experience with a large number of patients suffering from weight problems inspired him to write. This book puts forward the theory of "fixed weight" and combines it with the author's rich medical practice to provide an effective way for readers who really want to lose weight but can't stick to it. 2. This book is easy to understand and the language is interesting. Although it covers a multi-disciplinary background such as medicine, biology and geography, and has a lot of professional knowledge, the author uses less professional terms. Instead, he uses words and explanations that can be understood by the general public. He also uses pictures to help the public better understand the content. 3. This book focuses on the weight loss issue that is of concern and troubled all over the world. It explores the relationship between us and food from the perspective of metabolism, and points out the past mistakes that the public believed that failure to lose weight was due to poor self-control and the erroneous ways of dieting to lose weight. It helps readers to lose weight efficiently and healthily.