Kidneys perform a fundamental role in maintaining the body’s internal balance. They filter waste products, regulate fluids and electrolytes, and produce hormones. Many individuals can live full and healthy lives with only one kidney.
Kidney Function and Living with One
The kidneys filter about 120 to 150 quarts of blood daily, producing one to two quarts of urine of wastes and excess fluid. They also maintain a healthy balance of water, salts, and minerals, while producing hormones that control blood pressure, red blood cell production, and bone strength. When one kidney is absent or removed, the remaining kidney takes on the full workload.
This adaptation, known as compensatory hypertrophy, involves the single kidney increasing in size and filtering capacity. The remaining kidney can increase its filtration rate by 25% to 75% above its original capacity. This enables effective waste removal and regulation. Individuals may have only one kidney for several reasons, including donating a kidney, a common elective reason. Other reasons include surgical removal due to disease or injury (e.g., cancer or severe trauma), or being born with only one kidney (renal agenesis).
Potential Long-Term Considerations
Individuals living with one kidney generally experience good health, though some long-term considerations may arise. For most people, especially kidney donors, these risks are low. One consideration is a slightly increased risk of developing mild proteinuria, protein in the urine, over many years. This condition often indicates increased pressure within the kidney’s filtering units.
A modest chance of slightly elevated blood pressure may also develop later in life. Regular monitoring by a healthcare professional is important to detect these issues early for timely management. While rare, the remaining kidney could potentially fail due to injury, disease, or other unforeseen factors. Such an event would necessitate medical intervention.
Strategies for Optimal Kidney Health
Maintaining the health of a single kidney involves several proactive strategies. Adequate hydration is important by consuming enough water to support filtering processes. A balanced diet, limiting excessive sodium and processed foods, can also help reduce the workload on the kidney.
Managing blood pressure is important, as high blood pressure can strain the kidney. Regular checks and appropriate management through lifestyle changes or medication, if necessary. For individuals with diabetes, strict blood sugar control is important, as diabetes is a leading cause of kidney disease.
Caution with certain medications and substances is also advised. Avoiding nephrotoxic substances, like prolonged NSAID use (e.g., ibuprofen), certain herbal supplements, and recreational drugs, can protect kidney function. Regular medical check-ups, including blood and urine tests measuring creatinine, eGFR, and urinalysis, are important for monitoring kidney function over time. Preventing injury to the remaining kidney, such as avoiding contact sports, helps preserve its function.