First Time User? Sign Up Now
First Time User? Enroll now.
Home > Fitness & Health > Health Library > How the Kidneys Work
The kidneys are two bean-shaped organs located on either side of the spine, just below the ribs.
The kidneys filter wastes from the blood and help balance water, salt, and mineral levels in the blood. To do this, blood from the body enters the kidney. Inside the kidney, blood is filtered and waste is removed. Salt, water, and minerals are added if needed. The filtered blood is returned to the body and the waste from the blood is sent to the bladder as urine.
The kidneys also produce three important hormones: renin, erythropoietin, and the active form of vitamin D. Renin helps regulate blood pressure. Erythropoietin is needed to make red blood cells. Your body needs the active form of vitamin D to absorb calcium from food. Together, vitamin D and calcium help build healthy bones and maintain normal muscle function.
Blood flow to the kidneys is very important for the kidneys to work well. If blood flow to a kidney gets blocked, part or all of that kidney may die. This can lead to kidney failure.
Current as of:
December 17, 2020
Author: Healthwise StaffMedical Review: Anne C. Poinier MD - Internal MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family MedicineTushar J. Vachharajani MD, FASN, FACP - Nephrology
Current as of: December 17, 2020
Author: Healthwise Staff
Medical Review:Anne C. Poinier MD - Internal Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & Tushar J. Vachharajani MD, FASN, FACP - Nephrology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.