Can a Living Donor Kidney Fully Restore Kidney Function?

Donating a kidney is a life-changing gift—but what happens to the donor's health afterward? Many people wonder if one kidney can do the work of two.

This story looks at how the body adapts after donation and what long-term recovery really looks like.

Ann was diagnosed in 2016 with a rare genetic kidney disease that would eventually cause her kidneys to fail. Despite living a healthy lifestyle, her kidneys failed in March 2021, just as she was finishing her second year of nursing school. She started nursing to set an example for her five children, who each had a 50% chance of inheriting the disease. Dialysis was exhausting, especially as a single parent, and she struggled with fatigue while trying to manage daily tasks and work long hospital shifts.

Reluctant to ask for a kidney donor, Ann changed her mind after learning more about living donors’ health benefits. Inspired by someone from America who found a donor via social media, Ann posted her own plea online in late 2021.

The post went viral, being shared thousands of times, and soon people began coming forward to be tested. After some ups and downs, a perfect match was found in June 2022—a stranger who followed Ann’s story online.

The transplant was delayed due to COVID-19, but the donor stayed committed. They finally met before surgery and instantly connected. The transplant was successful, and Ann’s new kidney started working immediately. Though the donor faced some health issues afterward, she never regretted donating.

For Ann, small everyday milestones like cooking and playing with her children marked her recovery. Six months after the transplant, Ann finished her nursing degree and became a registered nurse.

Throughout her journey, she raised awareness about living organ donation and encouraged families to discuss their wishes. Ann also helped others facing similar struggles, including a dialysis patient who accepted a kidney from his wife after hearing her story. Ann credits her donor Nicola with saving her life and giving her children their mom back.

Kidney Function After Donation

Living donor kidney donation does not fully restore kidney function to the level it was before donation, but the body does an impressive job of adapting. After donating a kidney, there is an immediate drop in kidney function, typically around 25% to 40%. This is because the body no longer has two kidneys working together. However, the remaining kidney starts working harder, a process called compensatory hyperfiltration. This means the one kidney takes over much of the work that two kidneys used to do.

In fact, one study has shown that from six weeks after donation, the donor’s kidney function, measured by estimated glomerular filtration rate (eGFR), tends to increase slightly over time. On average, donors saw an increase of about 0.35 mL/min/1.73 m² per year, while healthy non-donors experienced a gradual decline of 0.85 mL/min/1.73 m² per year. The greatest recovery happened within the first two years after donation, with an average increase of 1.06 mL/min/1.73 m² per year. After five years, the eGFR mostly leveled off, showing almost no significant change.

Despite this impressive recovery, the kidney function in donors does not usually return to what it was before donation. At the end of follow-up, most donors had an eGFR between 60 and 89 mL/min/1.73 m². Only about 9.6% of donors had an eGFR over 90, compared to 56.8% of the healthy non-donor group.

This tells us that while the remaining kidney adjusts well, it doesn’t bring kidney function fully back to previous levels.

It’s also important to know that the risk of kidney failure after donation remains very low—less than 1% of donors develop end-stage kidney disease. Additionally, if a donor ever does need a transplant, they receive priority on the waiting list.

Takeaway

Living donation may not bring kidney function back to where it started, but the body works hard to adjust. The remaining kidney steps up, takes on more, and holds steady over time. Most donors stay healthy, with only a small number ever facing serious problems. If anything happens down the road, they’re not forgotten—they get priority care. This shows that living donation, while not perfect, can still offer strength, hope, and a second chance.