The kidneys, two organs located on either side of your spine just above the waist, perform several life-sustaining roles. They cleanse your blood by removing waste and excess fluid, maintain the balance of salt and minerals in your blood, and help regulate blood pressure.
When the kidneys become damaged, waste products and fluid can build up in the body, causing swelling in your ankles, vomiting, weakness, poor sleep, and shortness of breath. If left untreated, diseased kidneys may eventually stop functioning completely. Loss of kidney function is a serious — potentially fatal — condition.
Each bean-shaped kidney is 4 to 5 inches long and contains about a million nephrons, which are like tiny pouches. Each nephron has a filter at one end, called a glomerulus, to filter your blood. Your overall kidney function can be measured by how quickly blood is filtered through these glomeruli. This measurement is called the glomerular filtration rate.
Healthy kidneys handle several specific roles:
- Maintain your body’s balance of water and concentration of minerals such as sodium, potassium, and phosphorus in your blood.
- Remove waste by-products from the blood after digestion, muscle activity, and exposure to chemicals or medications.
- Produce renin, an enzyme that helps regulate blood pressure.
- Produce erythropoietin, which stimulates red blood cell production.
- Produce an active form of vitamin D, needed for bone health.