Why do we have kidneys?

Your kidneys are vital for your survival. They have several extremely important functions. Their main tasks are to filter waste substances out of your blood and balance the levels of salts and water in your body.

The location of your kidneys
Most people have two kidneys, although it is possible to live a normal life with one. They are shaped like beans. Their size is roughly the same as your fist. To find out where your kidneys are located, do like this: put your hands around your hips. Then slide them upwards until you can feel your ribs with your fingers. Your kidneys are then at the back, under your thumbs. You cannot feel them, but they are right there, well embedded in your body.

How your kidneys work
Depending on your weight, you have 4.5-6.5 liters of blood circulating in your body. This blood is transported into and through your kidneys by the renal arteries. Every day approximately 1500 liters of blood passes through your kidneys and is treated, thanks to roughly one million micro filters. These filters are called nephrons and are so small that you need a microscope to see them. Most kidney diseases are caused by attacks on the nephrons. When they lose their filtering abilities, dangerous levels of fluid and waste products can build up

Your blood needs to be cleaned
You have to eat food to build up your body and to get energy. When your body has taken what it needs, some of the waste products are sent back to your blood. One of the key functions of your kidneys is to continuously filter these waste substances out of the blood. You could say that your kidneys are the ‘cleaning station’ for your blood. They are sophisticated processing machines. If the kidneys do not remove the waste products, they will build up in the blood and severely damage your body.

Your kidneys have other functions
Your kidneys have other functions than cleaning your blood. They are important to balance the volume of fluids and minerals in your body. When you do not have enough fluids in your body, your brain tells your kidneys to hold on to it and tells you that you are thirsty. When you have too much fluid in your body your brain tells your kidneys to get rid of the excess.

Getting rid of wastes and water
The substances that are filtered in the kidneys are mixed with water and transformed into urine. The urine leaves the kidneys through the ureters and is collected in the bladder. When the bladder is about halfway full, you usually feel it is time to go to the toilet. When you urinate, the urine containing the waste products and water leaves your body through the urethra.

Kidneys are always busy
The kidneys also produce active vitamin D which is needed for absorbing calcium from the food. Calcium is among other things important for building your bones. In addition, your kidneys help regulate your blood pressure and stimulate the production of red blood cells. So, no doubt, the functioning of your kidneys is vital for your well-being.