A doctor reads a patient's blood pressure during a health check at the doctor's office.

Fuel for the Body and Vital All-Rounder

Even in ancient times, people knew that blood played an important part in the body, but without knowing the exact medical background. Today we know much more about the role of blood as a “liquid organ.” It also plays an important role in the body's healing process.

The Role of Blood

A doctor wearing white gloves takes a blood sample from a patient in an outpatient setting.

Medically speaking, blood is a tissue made up of solid and liquid components. Adults have around five to six liters of blood in their body. The heart acts as a pump driving blood circulation. Blood reaches almost all parts of the body via the vascular system – which incredibly is over 100,000 kilometers in length! Blood circulation is a closed system. The heart pumps up to 15,000 liters of blood each day through the vascular system and is thus connected to all other organs. Blood performs various vital transport and regulatory functions:

Medically speaking, blood is a tissue made up of solid and liquid components. Adults have around five to six liters of blood in their body. The heart acts as a pump driving blood circulation. Blood reaches almost all parts of the body via the vascular system – which incredibly is over 100,000 kilometers in length! Blood circulation is a closed system. The heart pumps up to 15,000 liters of blood each day through the vascular system and is thus connected to all other organs. Blood performs various vital transport and regulatory functions:

  • Supplying nutrients and oxygen to the body
  • Evenly distributing body heat
  • Transport of hormones and messenger substances for transmitting important information around the body – blood sugar level too low as a signal for food intake, for instance
  • Defense against pathogens using specialized cells (white blood cells and antibodies)
  • Using special cells and proteins to stop wounds bleeding

  • Supplying nutrients and oxygen to the body
  • Evenly distributing body heat
  • Transport of hormones and messenger substances for transmitting important information around the body – blood sugar level too low as a signal for food intake, for instance
  • Defense against pathogens using specialized cells (white blood cells and antibodies)
  • Using special cells and proteins to stop wounds bleeding

Composition of Blood

Blood cells are the solid components of blood. A distinction is made between red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). Blood cells are produced in bone marrow: "stem cells" divide and become platelets as well as red and white blood cells and their subtypes.

The liquid component of blood is blood plasma. This is 90% water and contains other substances including mineral salts, glucose (blood sugar) and proteins, metabolic products, enzymes and hormones.

A doctor wearing blue gloves extracts blood plasma from red blood cells in a centrifuge syringe.

Blood Counts

Only about 10% of white blood cells (leukocytes) are found in blood. Their name comes from the whitish color they have in unstained blood smears. Most white blood cells are found in bone marrow and tissues. They are an essential part of the immune system, neutralizing pathogens and therefore playing an important part in the defense against inflammation, infection or allergic reactions.

Platelets are produced in bone marrow. They are the most important element in blood clotting and hemostasis, as they form a plug that closes up the wound in the event of vascular injuries. When platelets fail to function properly, there is an increased tendency to bleed, causing wounds to bleed longer than usual.

By taking a blood sample and conducting various tests, doctors can draw a variety of conclusions about a person's health based on the composition of their blood. A blood count is used to check whether the distribution of blood cells corresponds to that of a healthy person. The blood count shows the results of counting the solid components in blood, ie, the red and white blood cells and the platelets. Blood counts for healthy people have many red blood cells, some white blood cells and some platelets.

Adults have around 30,000 billion red blood cells, which circulate in the blood for about 120 days before they die and are replaced by new ones. They are responsible for transporting oxygen from the lungs to the body. On the return journey, they carry some of the waste carbon dioxide to the lungs, where it is released and exhaled. An important component in erythrocytes is the red blood pigment hemoglobin. Its main task is to bind oxygen in the lungs and transport this to cells in the body.

ACP Therapy Uses Autologous Blood to Support the Body’s Own Healing Processes

Today, special therapeutic procedures are available that utilize the properties of blood in order to support the body's own regenerative abilities. These include ACP therapy. This is a type of autologous blood therapy and is mainly used by orthopedic surgeons and sports physicians in pain therapy, especially for the treatment of osteoarthritis, degenerative tendon injuries and acute sports injuries.

In ACP therapy, a special process is used to extract blood plasma from the patient's own blood. This plasma contains a very high concentration of platelets. These release growth factors directly at the injury site, which start to repair injured tissue by regenerating damaged cells. At the same time, tissue inflammation, responsible for swelling and pyrexia, is reduced. Inflammation reduces, so joints become less painful and more mobile.

A woman is smiling as she has her blood pressure taken by a doctor in an outpatient setting, using a cuff on her arm.

  • Supplying nutrients and oxygen to the body
  • Evenly distributing body heat
  • Transport of hormones and messenger substances for transmitting important information around the body – blood sugar level too low as a signal for food intake, for instance
  • Defense against pathogens using specialized cells (white blood cells and antibodies)
  • Using special cells and proteins to stop wounds bleeding

Frequently Asked Questions (FAQs)

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