Why is it possible for humans to live with only one kidney?

Humans can live with only one kidney because the remaining kidney is capable of adapting to filter blood and perform the necessary functions of waste removal and fluid balance on its own. The human body has a remarkable ability to compensate for the loss of one kidney by increasing the size and efficiency of the remaining kidney. Additionally, many people are born with only one kidney or may lose one due to injury or disease and still lead healthy lives without significant issues.