Blood in Chinese medicine and blood in Western medicine have both similarities and differences. Blood in TCM refers to the entire blood system, including its constituent roles, while blood in Western medicine emphasizes its components. In TCM, blood is mainly composed of vital energy and fluid. Blood is rich in nutrients and can nourish the internal organs. People’s energy, clarity of mind, sensitivity and agility of thinking all depend on the oxygenation of blood. Regardless of the reasons for the formation of blood deficiency or malfunction, there may be mental fatigue, forgetfulness, insomnia, dreams, irritability, palpitations and so on. Blood in Western medicine refers to the opaque fluid in the human circulatory system, consisting of plasma and blood cells, which include red blood cells, white blood cells and platelets. It has the functions of transportation, regulation of body temperature, defense, regulation of body osmotic pressure and acid-base balance. Consultation with a doctor is recommended for specialized medical issues.