What do the kidneys do in the human body?

The kidneys are two bean-shaped organs located on either side of the spine, just below the ribcage. Although small in size—roughly 10 to 12 cm (4 to 5 inches) long—they perform some of the most important tasks in the human body. Without properly working kidneys, your body would not be able to maintain balance or remove harmful waste.

The kidneys act as natural filters. They clean your blood by removing waste products and excess water, which then leaves the body as urine. Each day, the kidneys filter around 180 liters (about 48 gallons) of blood. This process helps to keep your internal environment stable and healthy.

One of the key functions of the kidneys is to regulate the balance of fluids and electrolytes, such as sodium and potassium. If there is too much or too little fluid, the kidneys adjust the amount of urine produced. This is why you may urinate more when you drink extra water and less when you are dehydrated.

The kidneys also help control blood pressure by managing the volume of blood in the body and releasing a hormone called renin. This hormone plays a key role in narrowing or widening the blood vessels as needed.

In addition, the kidneys produce a hormone called erythropoietin, which tells the bone marrow to make red blood cells. They also help convert vitamin D into its active form, which is necessary for strong bones.

In short, the kidneys do far more than just produce urine. They maintain the balance of fluids, filter out toxins, control blood pressure, support bone health, and help the body make red blood cells. Looking after your kidneys is essential for overall health.

If you have ever searched for questions like What is the main job of kidneys? or How do kidneys keep the body clean?, you are not alone. The kidneys are silent workers, but their role is vital every single day.

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