The common causative factors of hair loss are: first, reduced nutritional intake, protein is an important substance necessary to generate and nourish hair, but due to the hot and muggy weather, people like light food, meat food needs to be relatively reduced, if the body protein supply is not enough, hair will be easy to fall off. Second, eat too much cold drinks, research has found that if you eat too much cold food in summer, such as ice cream and other cold drinks, hair is easy to fall off. Third, thyroid disease, the first symptom of thyroid dysfunction is hair loss, too much or too little thyroid hormone will affect the metabolism and the normal growth of hair. Fourth, excessive heat radiation, summer ultraviolet radiation directly on the head, heat radiation on the human head skin produces strong stimulation, causing hair loss. The main factors in Chinese medicine are kidney deficiency and kidney essence deficiency for these reasons.