In order to understand more clearly, I need to clarify the definition of "weight loss" first, so as to avoid confusion. The performance of weight loss is usually weight loss, but weight loss is not necessarily (and often is not) weight loss, but it is probably caused by reduced body water (such as diuresis, catharsis). The weight loss we discuss here refers specifically to the reduction of body fat and does not include the reduction of water, because reducing water is meaningless.

　　There are many ways to lose weight, and there are many ways to lose weight, but it is really difficult to lose weight. Why? There are five basic reasons:

　　First, people are fundamental to the occurrence of obesity The reasons are not well understood, and it is easy to be fooled by those weight loss methods that seem to be shortcuts but are astray.

　　 Fundamentally speaking, obesity and weight loss are actually a very simple Newtonian mechanics problem. Newton''s laws of mechanics say that energy cannot be created out of thin air, nor can it disappear from thin air. It can only be transformed from one form to another. In the process of energy conversion, follow the law of conservation of energy. From the point of view of physics, the human body is actually a machine that metabolizes energy, ingesting energy (food) and then consuming it (basic metabolism, activities, etc.). When you consume more energy and consume less energy, the excess energy cannot disappear in a vacuum, and it will become fat stored in the body (obesity occurs); when you consume less energy and consume more energy, insufficient energy If it cannot be created out of thin air, it is necessary to use the fat in the body to convert it into energy (weight loss). Therefore, the fundamental way to lose weight effectively is to make the energy intake less than the energy consumed, that is to reduce energy intake (usually means eating less) and increase energy consumption (usually means hyperactivity), leaving these two premises, No weight loss method can be effective (except for direct cutting or fat extraction during surgery), otherwise Newton’s law of energy conservation will be wrong!

　　Second, the body does not have a direct way to excrete fat, the body can Drain, defecate, sweat, and waste, but not fat (no oil).

　　Urination, bowel movements, sweating, sauna, baking, squeezing, massage, electric shock, flicking, vibration, applying chili water, using soap reduction... It is impossible to lose fat from the body, Excrete or run away unless you have surgery to directly cut off or suck up fat. The only way to reduce fat (except for surgery to directly cut off or suck fat) is to let it be metabolized in the form of energy consumption (a popular saying is burning), if you want to consume fat to provide energy, you must (other than absolutely Nothing else) Make energy intake less than energy consumption, that is, reduce energy intake (usually means eating less) and increase energy consumption (usually means hyperactivity).

　　 Third, the innate “protection mechanism” of the human body is conducive to obesity and not conducive to weight loss.

　　 For example, when the food we eat (energy intake) decreases, the body will automatically lower the basal metabolism (energy consumption) to reduce energy consumption to avoid body fat loss. However, when we eat more food, the body does not automatically increase basal metabolism to avoid increased body fat. On the contrary, the human body can easily and unrestrictedly convert the excess energy into fat storage (the textbook says that there is no limit to the fat stored by human fat cells). It can also be found in life that when dieting reduces energy intake, hunger can make people consciously or unconsciously reduce the amount of activity to reduce energy consumption, but when we eat a big meal, a sense of fullness or overfulness does not make The human body automatically increases the amount of activity to increase energy consumption. So, in a sense, losing weight is the right thing to do with the "protection mechanism" evolved by the human body, which is of course difficult.

　　Fourth, weight loss usually requires changing people’s lifestyles, and changing one’s lifestyle is very difficult.

　　Although there is only one root cause of obesity (Newton’s Law of Mechanics), obese people do have their own reasons for gaining weight. For example, some people like to clean the leftovers of lettuce and eat one more bite every time. Eat a bite and become a fat man; some people eat too fast, and have eaten too much food before the gastrointestinal response is "full"; some people are too immobile and too lazy to go to the second floor They all have to take the elevator; some people like to drink drinks or snacks and inadvertently ingest too much energy. Therefore, if you want to lose weight, you must correct these habits. And common sense tells us that a person''s eating habits or lifestyles are formed for a long time and are very stable. Changes usually mean "uncomfortable", "painful", "unacceptable", in short it is very difficult.

　　 Fifth, the method of rapid fat reduction is not without, there are, but it is usually harmful to health and cannot be applied.

　　In fact, in terms of increasing the energy consumption of the human body, exercise is not the most "effective" method to increase the basic metabolism of the human body (that is, the energy consumed by maintaining basic temperature, heartbeat, breathing and other basic life activities ) Is the most effective method, because for most people, basal metabolism is the largest energy expenditure (accounting for 2/3 of the total consumption). The method of increasing basal metabolism is also very simple, (statement, I just for example and explain the problem, does not mean that I support or approve) taking thyroid hormone or drug use can greatly increase the basal metabolism, thus receiving good "Weight loss" effect. However, such weight loss is very harmful to health and can even be life-threatening. As far as I know, there is no way to lose weight that can significantly increase basal metabolism and is not harmful to health. Although adherence to exercise can increase basal metabolism, the range is relatively limited, and the effect is not obvious.

　　In short, the principle of weight loss follows Newton’s laws of mechanics, the body does not have a channel to excrete fat, the existence of the body’s evolved protection mechanism, makes it difficult for people to change their fat lifestyle, and “effective” weight loss methods endanger health. The reason makes it very difficult to lose weight.