The average adult has about 10 pints of blood (about 8% of body weight). It takes about 1 pint to donate blood, after which your body has an amazing ability to replace all the lost cells and fluids.

erythrocyte

Take the red blood cells. Millions of products are made and die every second. When you donate blood, you lose red blood cells and your body needs to make more red blood cells to replace them. Specialized cells in the kidneys, called peritubular cells, sense the drop in oxygen levels in the blood (due to the loss of red blood cells) and begin secreting a protein called erythropoietin. It travels through the blood until it reaches the bone marrow (the soft fatty tissue within the bone cavity).

The bone marrow produces stem cells, which the body uses to make different blood cells – red blood cells, white blood cells and platelets. Erythropoietin sends messages to stem cells, telling more stem cells to develop into red blood cells instead of white blood cells or platelets.

How quickly does your body make blood?

Your body produces about 2 million new red blood cells every second, so it only takes a few weeks to store them again.

How are your white blood cells and platelets? Many other messenger proteins also stimulate the production of these cells in the bone marrow, which returns to normal over the next few days.

How long is the interval between donating blood?

Male donors need to wait at least 12 weeks between whole blood donations, and female donors need to wait at least 16 weeks. So why wait? Unlike white blood cells and platelets, it takes several weeks for all red blood cells to be replaced. You can schedule an appointment at an appropriate distance using our online appointment system.

There is an important connection between red blood cells and your health because it is these cells, or rather the red hemoglobin they contain, that absorb oxygen around your body. Heme contains iron, and some iron is lost every time you donate blood. To compensate, the body mobilizes iron from its own iron stores, and the body also increases the amount of iron it absorbs from food and drink. Men generally have greater iron stores than women.

your hemoglobin levels

Before each donation, we test your hemoglobin levels. We ensure that the hemoglobin level is above 125 g/L for women and 135 g/L for men. This is because any iron deficiency can lead to low heme levels, which can eventually lead to iron deficiency anemia if left untreated. This deficiency can make you feel tired.

your iron levels

The body stores iron in the form of two proteins - ferritin (about 70% of stored iron in men and 80% in women) and hemosiderin. These proteins are found in the liver, bone marrow, spleen and muscles. If too much iron is removed from stores rather than replaced through dietary sources, iron stores may become depleted and heme levels may drop.

After donation, most people's hemoglobin levels return to normal within 6 to 12 weeks. That's why we ask donors to wait at least 12 weeks between donations (12 weeks for men, 16 weeks for women) to ensure we don't risk lowering your hemoglobin levels long-term.

Drink water

Blood volume accounts for approximately 8% of body weight. About 55% of blood is made up of plasma, of which 90% is water. So even though you donate less than a pint of blood at a time, almost half of it is water. That's why it's important for you to drink plenty of water before and immediately after donating. It is important to change fluids after donating blood to help return your blood volume to normal. The kidneys also control blood volume by regulating the loss of sodium and water in the urine.