It is possible to live with one kidney. People may have one kidney because they either donated the second kidney, lost a kidney during surgery or they may have been born with only one kidney.
People born with only one kidney compensate for this by enlarging the second kidney. This is known as regenerative growth. The remaining kidney grows faster and larger to take on the work of two kidneys. Sometimes the remaining kidney doubles in size to meet this need.
Most people with one kidney lead normal healthy lives, according to Kidney.org. Still, these individuals are advised to check their kidney function at least once a year.