What does cold 7 mean?

Cold 7 is cold, which is the saying of Chinese medicine. Chinese medicine says that cold is the source of all diseases, and any exogenous evil with cold, coagulation and inhalation characteristics is called cold evil. Cold pathogens are more common in winter. When water and ice freeze, many people are frostbitten, so it is often very cold in winter. But cold evil can also be seen in other seasons, such as the sudden drop of temperature and the wading of air conditioners in the rain. This is often an important reason for feeling cold evil. Severe cold in the body is caused by yang deficiency and cold invasion. People who catch too many colds will have yang deficiency, and are prone to symptoms such as chills, cold limbs, pale face and diarrhea, which are more complicated and diverse.