Many individuals lead full and healthy lives with only one functioning kidney. While the thought of relying on just one of these vital organs can understandably cause concern, the human body often demonstrates a remarkable capacity for adaptation. Understanding why someone might have one kidney, how the body adjusts, and what measures to take for proper care can provide reassurance and empower individuals to maintain their well-being.
Why Someone Might Have One Kidney
Individuals can have a single kidney for several reasons, ranging from conditions present at birth to medical interventions later in life. One common reason is congenital absence, known as renal agenesis, where a person is born with only one kidney, or kidney dysplasia, where two kidneys are present but only one is functional. Beyond congenital factors, surgical removal of a kidney, termed nephrectomy, is a frequent cause, often necessary to treat serious conditions such as kidney cancer, severe injuries, or large kidney stones. Additionally, a growing number of people become living kidney donors, voluntarily giving one of their healthy kidneys to a family member, friend, or even a stranger in need of a transplant.
How Your Remaining Kidney Adapts
The human body possesses an impressive ability to adapt, and this is particularly evident when an individual has only one kidney. The remaining kidney often undergoes a process called compensatory hypertrophy, meaning it physically grows larger and its individual filtering units, called nephrons, increase in size and function. This enlargement allows the remaining kidney to significantly increase its filtering capacity, often reaching about 70% to 85% of the function normally performed by two kidneys. While the single kidney is working harder, this adaptation typically enables it to adequately filter blood and maintain the body’s balance of fluids and minerals. However, this increased workload necessitates careful long-term monitoring.
Essential Lifestyle Adjustments
Maintaining the health of a single kidney involves adopting specific lifestyle habits.
Hydration and Diet
Adequate hydration is important; drinking plenty of water helps the kidney efficiently clear waste products like sodium and urea from the body. While there is typically no need for a special “renal diet,” a balanced eating plan generally includes more fruits and vegetables, and less processed foods. Moderate protein intake is often advised to avoid overworking the kidney, and limiting sodium to less than 2,300 mg per day can help manage blood pressure, which is beneficial for kidney health.
Physical Activity
Regular, moderate physical activity, such as walking or swimming, promotes overall well-being and helps control blood pressure. However, individuals with one kidney should discuss participation in contact sports with their doctor to minimize the risk of injury to the remaining kidney.
Medications and Substances
Awareness of medications is also important. Certain over-the-counter pain relievers, particularly non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, can affect kidney function and should generally be avoided unless specifically advised by a medical professional. Finally, avoiding or significantly limiting smoking and alcohol consumption is beneficial, as both can negatively impact kidney health and overall circulation.
Ongoing Medical Care
Regular medical follow-ups are a cornerstone of living with one kidney to ensure its long-term health. These routine visits, ideally with a nephrologist or primary care physician, allow for continuous monitoring of kidney function.
Common tests include blood tests to measure creatinine and estimated glomerular filtration rate (eGFR), which indicate how well the kidney is filtering waste. Urine tests, such as the urinary albumin-to-creatinine ratio (uACR), are also performed to check for protein in the urine, which can be an early sign of kidney damage.
Controlling blood pressure is also a significant aspect of care, as hypertension can damage kidney blood vessels over time. Early detection of any changes allows for timely intervention and adjustments to the care plan.