Most people are born with two healthy kidneys. There are some people who are born with only one healthy kidney, and they may never know they only have one unless they have an x-ray or ultrasound and then find out.
You can live a long life with one healthy kidney!
Then why do we have two? Great question. I don’t know …
If one kidney is damaged (like in a car accident) and no longer works, it is great to have another one that can clean your blood and keep you alive. Some people get cancer in one kidney and it can be removed and your other one keeps working. But in those cases, having two of any organ would be helpful.
However, most people with kidney problems have kidney disease, not cancer or an accident. When you have kidney disease, it affects both kidneys. That means both kidneys are “sick” and can’t clean your blood like they are supposed to. The disease might keep getting worse until your kidneys can’t keep your blood clean and keep you alive. That is when you would need to be on the kidney machine (dialysis), or get a kidney transplant, or you will die. Having two kidneys does not help in this situation.
Dialysis does the job of cleaning your blood like your kidneys used to do. Typically, you will still have your two bad kidneys, but they get smaller and are not a problem. They just sit there not working. Dialysis does not clean your blood as well as a healthy kidney, so you would feel sick much of the time and have little energy. Many people on dialysis are so sick that they are not able to work anymore.
You could also get a kidney transplant before you start dialysis. This is even better for your body and you live longer than if you start dialysis first.
If you get a kidney transplant, you only receive one kidney. You could get this kidney from someone who died, or someone alive who wants to donate a kidney. A living person only needs one kidney and they can give one to you! You only need one working kidney to get you off dialysis because this one healthy kidney would clean your blood and you would feel more normal again with more energy. And many people are able to go back to work after a kidney transplant.
People who get kidney transplants often have three kidneys! One healthy kidney and two that are not working. If the transplanted kidney gets diseased and stops working, you might need another kidney transplant. Then you might have four kidneys; one healthy kidney and three that are not working.
Maybe the reason we have 2 kidneys is to give 1 away …
How Many Kidneys Do You Have?
Glenna Frey, APRN-CNS, is a nephrology nurse who donated her kidney in April 2017 to a stranger. She and daughter Amanda Frey co-founded Kidney Donor Conversations in 2018 to increase awareness of Living Kidney Donation.
Image Credit: https://www.flickr.com/photos/hey__paul/