What is the purpose of the kidneys?

The kidneys are some of the most important organs in your body, and each one contains many parts. Learn more about the main structures of the kidneys and how they function. read more

Polycystic kidney disease , for example, is a genetic disorder in which many cysts grow in the kidneys. PKD cysts can slowly replace much of the mass of the kidneys, reducing kidney function and leading to kidney failure. Some kidney problems may show up when a child is still developing in the womb. read more

Healthy kidneys filter about a half cup of blood every minute, removing wastes and extra water to make urine. The urine flows from the kidneys to the bladder through two thin tubes of muscle called ureters, one on each side of your bladder. Your bladder stores urine. Your kidneys, ureters, and bladder are part of your urinary tract. read more

But the kidneys also are important for other reasons. The kidneys release three hormones: one that stimulates the bone marrow to produce red blood cells, another that helps regulate blood pressure, and the third is actually the active form of vitamin D, which helps maintain calcium levels. read more