Cordyceps sinensis, ginseng and pilose antler are listed as the three "tonics" in China. As early as 1757, in Materia Medica, it was recorded that "Cordyceps sinensis is sweet and flat to protect lung, benefit kidney, replenish essence, stop bleeding and resolve phlegm, and it is good to treat diaphragmatic disease". Cordyceps sinensis is flat in nature, and there is no big side effect after taking it. Those who are weak can make up for it. Cordyceps sinensis, also known as Cordyceps sinensis, is essentially a fungus-Cordyceps sinensis of Ergonomidae. It is called "Cordyceps sinensis" because of its production process. In order to reproduce, bat moths will lay eggs in the soil, and the eggs will then become larvae. Cordyceps sinensis will invade the larvae, absorb their nutrients, and continue to multiply, so that the larvae are full of hyphae and die. This is called "Cordyceps sinensis". In the summer of the following year, Cordyceps sinensis grew a purple grass with a height of 4-10 cm on the head of the larva, which was called "summer grass". "Summer grass" emerges from the ground, is dug and dried, and becomes what you usually see. Cordyceps sinensis is suitable for lung and kidney deficiency, essence deficiency, cough with shortness of breath, spontaneous sweating and night sweats, soreness of waist and knees, impotence and nocturnal emission, cough with phlegm and blood. Because of its mild medicinal properties, compared with other tonics, it has a wider range of medicinal and edible properties, and is a good tonic for the elderly, the weak after illness and the weak after childbirth. For example, patients with renal failure, tumor receiving radiotherapy and chemotherapy, or patients who have just finished surgery can eat one or two Cordyceps sinensis every day. It is recommended to make tea with Cordyceps sinensis and drink several cups a day. When the Cordyceps sinensis is soft, you can chew it and swallow it. But after all, Cordyceps sinensis is a tonic, which is not suitable for all people. It is best not to eat it for those with a hot constitution. Modern people's diet is greasy, often with big fish and big meat, and many people have phlegm heat in their bodies, so the accumulated metabolites can't be discharged. Because of heavy work pressure and fatigue, they often eat cordyceps sinensis for tonic. But fatigue is not necessarily a sign of physical weakness. Except for those who are physically weak after illness and postpartum, others should eat Cordyceps sinensis, and it is best to consult a doctor in the hospital first. If you blindly take supplements, you may get angry, and excessive use will also lead to palpitation, shortness of breath, irritability, erythema on your face and edema of your limbs. At present, there are many counterfeit Cordyceps sinensis in the market, and people often use Cordyceps sinensis as counterfeit. Cordyceps sinensis is found in most parts of China, but it is especially precious only in Qinghai, Tibet, Sichuan, Yunnan, Guizhou and Gansu. It is best to go to a regular pharmacy to buy Cordyceps sinensis. Generally, you can refer to the following five standards: First, the body is complete and plump. Cordyceps sinensis looks like a silkworm. It is about 3-5 cm long and 0.3-0.8 cm thick. The second is to observe the ring pattern. The ring pattern of Cordyceps sinensis is rough and obvious, and the ring pattern near the head is fine, with 20-30 ring patterns. The third is the outer Huang Liang, and the inner color is white. The appearance of Cordyceps sinensis is dark yellow or yellowish brown. The fourth is to identify from insect feet. Cordyceps sinensis has 8 pairs of feet, 3 pairs near the head, 4 pairs in the middle, 1 pair in the tail, and 4 pairs in the middle are the most obvious. The fifth is to identify from the fruiting body of the head. The fruiting body of the head of Cordyceps sinensis is dark brown, cylindrical, 4-8 cm long and 0.3 cm thick, with fine longitudinal wrinkles on the surface.