We cannot live without blood. Our entire body is supplied with it through our heart, arteries, veins and vessels. We explain to you what blood is and what functions it has.
What is blood?
Human blood is a water-based fluid that circulates throughout the body. For example, blood transports oxygen, nutrients, hormones and antibodies throughout the body. It also removes waste products, ensures that our body temperature is maintained and protects against diseases. The amount of blood in the body depends on several factors, such as age, gender and weight. But where you live can also have an influence. People who live at high altitudes have to deal with less oxygen in the air. The body therefore produces extra blood. Adults have about 4 to 6 liters of blood in the body. This is between eight and ten percent of an average body weight. Newborn babies have only 300 to 400 milliliters of blood in the body.
Our blood consists of approximately 45% blood cells and 55% fluid. The liquid part is called blood plasma. This plasma consists mainly of water, but also contains proteins, salts, antibodies, hormones, enzymes, fats and... glucose. Plasma transports substances, controls body temperature and regulates blood circulation and blood pressure. The substances in the blood plasma also protect against viruses and bacteria, for example.
How much blood does someone have?
On average, an adult woman has 4,5 liters of blood and an adult man has 5,6 liters of blood. This blood is pumped by the heart in a system of arteries, veins and capillaries.
Blood cells
In addition to plasma, blood consists of platelets and both red and white blood cells. The red blood cells make up about 40% of the blood volume. They are much more common than platelets and white blood cells. They contain hemoglobin, which ensures the transport of oxygen in our body. Oxygen is transported from the lungs to the tissues and organs. Hemoglobin determines how much oxygen your body can absorb. In case of a shortage of red blood cells or when the red blood cells do not work properly, this is possible anemia to arise. In that case the hemoglobin level is too low. The white blood cells ensure a properly functioning immune system. Antibodies are produced that recognize the pathogens and then eliminate them. The platelets ensure that the blood clots at the right time. This is necessary in case of a cut or wound, for example.
Bone marrow
The red spongy part in the bones, also called bone marrow, produces new red blood cells, white blood cells and platelets. The blood cells have a limited lifespan and the old blood cells are removed by the bone marrow and spleen. Red blood cells last about 4 months. Platelets about 6 days. White blood cells can die within a day, but can also survive longer.
What is Blood Sugar?
Carbohydrates are absorbed into the blood in the form of glucose. The body cells need glucose as fuel. Absorption takes place in the intestinal wall during the digestion of food. Body tissues, such as muscles, absorb the glucose and burn it, giving you energy. Glucose in the blood is also called blood sugar. An excess or deficiency of glucose in the blood is prevented by the hormones glucagon and insulin. They ensure a balance of blood sugar levels.
Insulin
When you eat a lot of carbohydrates, your blood sugar level rises. The insulin then ensures that the glucose can be quickly absorbed by the tissue. Too high a blood sugar level is also called hyper. When the blood sugar level is too low (hypo), the hormone glucagon is produced. This in turn ensures the balance. Diabetes patients often have to deal with high blood glucose levels because the body produces too little or no insulin. Insulin is therefore treated with a pen needle manually injected into the subcutaneous fatty tissue, between the skin and the muscles. It does not enter the blood directly, but is then gradually absorbed by the blood. This prevents major fluctuations in blood sugar levels.