What kidneys do

If organs had careers, your kidneys would be chemists. These bean shaped organs, located in the middle of your back, may be small (each one is about the size of a fist), but they perform extremely important tasks. Kidneys process, clean and balance the entire body’s blood supply every 5 minutes. Approximately 200 quarts of fluid are processed through your kidneys every 24 hours. 

Most people know that the kidneys’ primary function is cleaning the blood by removing waste and excess fluid from the body through urine production. But that’s only the half of it. Your kidneys perform all of these functions: 

  • Remove waste products from the body
  • Balance the body’s fluids
  • Control blood pressure
  • Regulate the body’s mineral and acidity levels
  • Activate vitamin D to regulate bone health
  • Help stimulate the production of red blood cells

Kidneys clean wastes from your blood

The kidneys perform a life-sustaining job by cleaning wastes and excess water from the blood. Each kidney has a million filtering units called nephrons that consist of tiny blood vessels. As your blood travels through the kidneys, they filter out toxins and excess liquid from your body. The excess water and wastes are stored in the bladder and leave the body when you urinate. Around 2 quarts of urine are produced every 24 hours.       

Kidneys maintain the fluid in your body

Your body’s principal chemical component is water. The Mayo Clinic states, “60% of body weight is water.” The importance of maintaining a healthy fluid intake is crucial. Water flushes toxins from vital organs, carries nutrients to every cell of your body, and maintains hydration throughout the body. Your kidneys regulate this important balancing act. When there is an excess of water, the kidneys filter it from the blood and produce urine.

Kidneys help control your blood pressure

In addition to removing excess sodium and fluid, your kidneys help control blood pressure by releasing an enzyme called renin. Renin’s primary job is to maintain healthy blood pressure. If your blood pressure drops and the kidneys aren’t receiving enough blood, renin is produced, causing blood vessels to tighten and blood pressure to rise.  

Kidneys regulate your blood’s acidity and mineral balance

The precise chemical balance of your body is regulated by the kidneys. They maintain your blood’s perfect ratio of acidity and minerals, which include sodium, calcium, potassium, chloride, sulfate, phosphate, hydrogen and magnesium.  By controlling the body’s chemistry, the kidneys help every organ, including the heart. Kidneys also help strengthen your bones by producing an active form of vitamin D. 

Your kidneys help build red blood cells

Red blood cells represent approximately 36 – 44% of your blood content. Your kidneys produce a hormone called erythropoietin that signals your body’s bone marrow to make red blood cells. The red blood cells carry oxygen throughout your body to all your organs. Oxygen is crucial for your body function well.  

How to help your kidneys function

Sometimes your kidneys need a helping hand. Regular visits to your doctor and taking prescribed medicine correctly can make a positive difference. You should also consult your doctor if you are taking over-the-counter medicines or any herbal or nutrient supplements, because these may interfere with your prescribed medication. In addition, some over-the-counter medications such as pain relievers can be harmful to your kidneys if they are taken in large amounts and/or over a long period of time. 

Maintaining a healthy weight and diet can also help a great deal. Moderate exercise can lower high blood pressure, which can keep your heart and kidneys healthy. By adopting a kidney-friendly lifestyle, you can improve your quality of life. It’s important to consult your doctor before you begin an exercise program. 


Your kidneys are your body’s master chemists. Kidneys maintain the chemical balance of your body by cleaning your blood supply, producing hormones and enzymes and managing proper fluid levels. And those are just some of the important things kidneys do.

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