Blood makes up about eight percent our body weight and contains 20-30 trillion red blood cells – about one quarter of the cells in our body. Each of our physical organs performs a service for the blood, and with five liters of it flowing throughout our systems, it in turn performs essential functions for the body. Such is blood, and it is the essence of life.

Blood serves as a remarkably efficient transport system. The oxygen we inhale, the nutrients and water we consume, and the hormones needed to regulate our body, all of these rely on the blood system in order to reach the 100 trillion cells in our bodies.

While delivering these life-giving elements, blood also removes the harmful metabolic waste products from the cells of the body. The waste is removed from our bodies through breath, sweat, urine and stool.

Blood also provides a protection system for our bodies. The immune system, the white blood cells, protects the body from foreign agents in the environment, such as the bacteria in food, water and the air. It also protects us from dangers from within; our blood defends us from the quadrillions of bacteria that reside in and on our bodies. It also forms antibodies in response to infection from bacteria, viruses, and parasites from the environment.

Lastly, blood protects itself. Blood can prevent its own flow by clotting damaged blood vessels using platelets. Blood must continuously flow through the body’s vast network that makes up the blood stream; if any red blood cells escape from blood vessels or if blood stops flowing, it will clot. This delicate balance between clotting to prevent hemorrhage and not clotting when the blood is flowing normally is essential to life.