What is the relationship between blood deficiency and hair loss?

Qi deficiency may cause hair loss.

According to TCM theory, hair growth and health are closely related to the filling degree of qi and blood inside the body. Qi and blood are regarded as important substances to nourish tissues and organs of the whole body in TCM theory. Hair is provided with nutritional support by hair follicles, and the growth and development of hair follicles require sufficient qi and blood supply. If qi deficiency occurs, the nutrient supply of hair will decrease, resulting in weakening of hair follicles and easy shedding. In addition, hair growth is regulated by kidney essence, and insufficient qi and blood may affect the kidneys, reducing the production of kidney essence, resulting in disorder of hair growth cycle, shortening the growth period and prolonging the rest period, thus accelerating the hair loss process.