Kidney

The kidneys are a pair of bean-shaped organs that filter waste and excess water from the blood to produce urine.

Function

Blood passes through the kidneys, which remove waste products and balance the body's water, salts and minerals. The cleaned blood returns to the body, while waste leaves as urine.

Health

Healthy kidneys are vital; when they fail, treatments such as dialysis or a transplant may be needed.

Frequently asked questions

What do the kidneys do?

They filter waste from the blood and make urine.

How many kidneys do humans have?

Two.