IMPORTANCE OF WATER IN THE KIDNEY Water is clearly the most important nutrient and the most abundant substance in the human body. Water comprises about three quarters of the human mass and is a major component in every cell. One of the main jobs of the kidneys is to filter the waste out of the blood. The kidneys filter that blood as many as 400 times a day! The waste that is collected combines with water (which is also filtered out of the kidneys) to make urine.

Your body gets water when you drink it or other liquids. You also get water from some foods, like fruits and vegetables. Water leaves your body in several ways. It comes out of your skin when you sweat, out of your mouth when you breathe, and out of your urethra in urine when you go to the bathroom. There is also water in your bowel movements (poop).

When you feel thirsty, your brain is telling you to get more fluids to keep your body as balanced as possible. If you don't have enough fluids in your body, the brain communicates with the kidneys by sending out a hormone that tells the kidneys to hold on to some fluids. When you drink more, this hormone level goes down, and the kidneys will let go of more fluids.

While the blood is in the kidneys, water and some of the other blood components (such as acids, glucose, and other nutrients) are reabsorbed back into the bloodstream. Left behind is urine.

Kidneys perform several important functions: They regulate water. To function properly, your body must have the right amount of water. Kidneys remove excess amounts of water from the body or retain water when the body needs more. Not drinking enough fluids, especially water can Causes Kidney Stones.