People have heard that "medicine and food have the same origin". Strictly speaking, this statement is related to health preservation. This is illustrated in the earliest classic of traditional Chinese medicine Shennong materia medica classic. Origin of traditional Chinese Medicine The reason why Shennong's herbal classic is named after "Shennong" comes from a well-known story of "Shennong tasting hundreds of herbs". "Huai Nan Zi · Xiuyue Wu Xun" said that Shennong "tasted the taste of grass and the joys and sorrows of water springs, so that the people could avoid it. At this time, he encountered 70 poisons in a day". Here is the reason why Shennong "tasted all kinds of grass". "Let the people know what to avoid", "avoid" is to avoid, and those poisonous should be avoided; "Just" is close, non-toxic and beneficial can be close to pick. It can be seen that he tried Baicao in order to find safe food for people. After tasting, record the sour, pungent, bitter, sweet and salty tastes of wild vegetables, wild fruits, seeds or plant roots, as well as various physical feelings and reactions after eating. For example, after eating some plants, the human body reacts strongly, causing vomiting, diarrhea, even coma and death. However, after eating some plants, the original pain on the body can be alleviated or even cured. In this way, the knowledge of "medicine" can be accumulated. This is the "homology of medicine and food" in traditional Chinese medicine. Of course, "taste a hundred herbs" is a general term. Food and medicine are not only "grass", but also many animals and minerals. The process of their discovery is similar. With the development of hunting and fishery, primitive people obtained more meat, fish and clam food. Gradually, people realized that the fat, blood, internal organs, bones and shells of some animals had edible value or therapeutic effect, so as to accumulate animal medicine knowledge. At the end of primitive society, people began to engage in mining, smelting and other production activities. With the deepening understanding of minerals, human beings have also mastered the properties of some minerals, such as mirabilite, sulfur and skin diseases. It is only because the plant medicine accounts for the majority in traditional Chinese medicine, so we call it "Shennong tastes all kinds of herbs" for short, and call traditional Chinese medicine "Materia Medica". The boundary between medicine and food Shennong herbal classic contains 252 kinds of plant drugs and 67 kinds of animal drugs, basically including the commonly used drugs of modern traditional Chinese medicine. The book not only describes the name, taste, efficacy and indications of drugs, but also records their synonyms and origin. One of the most prominent features of this book is the three product classification. The three grades are the upper, middle and lower grades. The classification principles are as follows: "One hundred and twenty kinds of herbs are used as the king. They are mainly used to support people's life. They are non-toxic. Taking them for a long time will not hurt people. Those who want to lighten their body and replenish their Qi and prolong their life should follow the Sutra. One hundred and twenty kinds of traditional Chinese medicines are used as officials. They are mainly used to support people. They are non-toxic and should be considered as appropriate. Those who want to curb diseases and tonify deficiency should follow the Sutra. 125 kinds of herbs are used as assistant envoys. They are mainly used to treat diseases in the place. They are multi poisonous and should not be taken for a long time. In order to eliminate the evil Qi of cold, It can be seen from this that the classification of the three products is mainly distinguished by the strength of their effects on the human body. Among them, the top product "supports life and responds to the sky". The so-called "lighten the body and replenish qi" and "prolong life" Obviously, it belongs to the content of health care and disease prevention. It means that most of the top quality medicines can be used as health care and longevity, most of them have the function of strengthening the body and resisting aging. The ginseng, astragalus, Poria, rehmannia, Eucommia ulmoides, and wolfberry can be used for a long time, but it has great effect on health. However, because this book is obviously influenced by Taoist alchemy's thought, the top quality medicine is also very important. There are many mineral drugs in Chinese medicine. From the practice of later generations, they are not conducive to health preservation, and may even hurt students. We should pay attention to screening. The middle grade "mainly nourishes people in response to people" can "curb diseases and supplement deficiency and gain" It shows that the drugs can also be selectively used as tonic and dietotherapy, which are also commonly used in health preservation, such as lily, Angelica sinensis, longan, pilose antler, Coptis chinensis, ephedra, Angelica dahurica, etc. the inferior products "mainly treat the disease to the place", and many toxic ones can dispel evil and break the accumulation, such as rhubarb, Aconitum, kansui, Croton, etc. they are usually not used for dietotherapy when there is no disease. It can be seen that there is a boundary between food and medicine. Theoretically, the "top-grade" medicine can be used as food, and has better physical fitness value than ordinary grains. The "middle-grade" medicine is suitable for people, and it needs to distinguish different physique. For some people, it is equivalent to taking nourishing nutrients, but for others, it is not applicable. "Bottom-grade" In principle, the medicine is only used for curing diseases and should not be used as food. This classification principle of Shennong materia medica classic is very meaningful. It points out that health preservation comes from life, but its goal is higher than ordinary life. It is a more purposeful activity to maintain healthy life. In Shennong materia Medica classic, the efficacy terms related to health preservation include light body and prolong life (or endure aging, increase age, grow old, etc.), fat and healthy (or grow muscle), endure hunger (or do not hunger, etc.), not old, intelligent ears, clear eyes, calm the mind (or calm the soul, strengthen the soul, calm the mind), benefit intelligence (or be intelligent, increase wisdom, be smart, strengthen ambition, do not forget), good color (or face brilliance), etc. in addition, there are "immortals" Today, the state has issued the list of items that can be used for health food, the list of items that are both food and medicine, and the list of prohibited items for health food , in a sense, it is the top-grade, middle-grade and bottom-grade medicine for health care. It can be seen that the concept of homology between medicine and food has been implemented in practice since ancient times. Food should not be used. What we said earlier is that different varieties of drugs should pay attention to their interests to the human body. Similarly, ordinary food should also distinguish their interests when eating and avoid "eating diseases" This is specially discussed in another famous ancient Chinese medicine book synopsis of the golden chamber. The two articles "taboos and treatment of animals, fish and insects" and "taboos and treatment of fruits, vegetables and grains" in this book talk about a very rich knowledge of dietotherapy. It says: "where the taste of diet is based on health, eating is harmful, but it can be harmful." It means that food is supposed to nurture life, but improper eating will also be harmful to life, and sometimes the problem is very serious. Therefore, it says: "the taste of food is appropriate to disease and harmful to the body. If it is appropriate, it will benefit the body, and harm will become disease. It is difficult to cure any case of danger." The synopsis of the Golden Chamber talks about many principles, such as: "liver disease forbids bitterness, heart disease forbids saltiness, spleen disease forbids acid, lung disease forbids bitterness, and kidney disease forbids sweetness. Do not eat liver in spring, heart in summer, lung in autumn, kidney in winter, and spleen in four seasons." These statements are not absolute taboos, but they suggest the principle of avoiding eating certain types of food in different seasons. There are also some specific experiences on dietary hygiene, such as "meat and fish, if dogs do not eat, birds do not peck, they cannot eat", "those with red dots in the meat cannot eat", "plum can eat more, bad people's teeth" and "pears can't eat more, which makes people cold" It is not difficult to see that these food taboos not only come from life experience, but also reflect the guidance of the theory of traditional Chinese medicine, which is another embodiment of the "homology of medicine and food". (Xinhua)