Living With One Kidney: Health, Risks and Care

Can You Live With One Kidney?

Most people are born with two kidneys, but it is possible to live a healthy and full life with just one. Whether you have undergone kidney donation, lost a kidney to disease or injury, or were born with a single functional kidney, your remaining kidney is typically able to adapt and take on the work of both.

How Common Is Living With One Kidney?

Living with only one kidney is more common than many realize. Some people are born this way—about 1 in 1,000 babies are born with a single kidney, and another 1 in 1,000 may have two kidneys but only one that functions correctly. Many others lose a kidney later in life due to surgery, injury, or kidney donation. Thanks to the body’s remarkable ability to adapt, most individuals with just one healthy kidney experience minimal, if any, effects on their everyday health and lifespan.

How Your Body Adapts

Your single kidney usually increases in size and function to compensate for the loss of the other. This process, called hypertrophy, enables the remaining kidney to handle about 70-80% of the workload typically performed by two kidneys.

• Increased function: A single kidney can filter blood and maintain fluid balance nearly as efficiently as two kidneys.
• Adaptation over time: If you were born with one kidney, its growth and function usually develops normally. If you lost a kidney later, your remaining kidney adapts to the increased demand.

Reasons Why Someone Has One Kidney

• Kidney donation: Being a living donor for someone in need of a transplant is one of the most common reasons adults live with one kidney.
• Congenital absence: Some people are born with a single kidney (renal agenesis) or with only one functioning kidney (kidney dysplasia).
• Surgical removal: A kidney may be removed because of cancer, trauma, infection, or severe kidney disease.
• Injury: Trauma can result in the loss or removal of a kidney.

General Health With One Kidney

For most people, having one normal, healthy kidney causes few if any symptoms or problems, especially in the first years after losing or donating a kidney. Research and many years of clinical observation confirm:

• Normal daily life: People with one kidney typically lead lives that are as long and active as those with two kidneys.
• No noticeable symptoms: Most adjust well and cannot distinguish any difference in their wellbeing.
• Mild decrease in kidney function: There may be a small reduction in overall kidney function, but this usually does not impact health.

Possible Complications and Long-Term Risks

While most people experience minimal effects from having one kidney, some possible risks are slightly increased compared to the general population:

• High blood pressure (hypertension): The risk is modestly increased, particularly over the long term.
• Proteinuria: A higher chance of having protein (albumin) leak into the urine, which can be a marker of kidney stress or early kidney damage.
• Chronic kidney disease (CKD): Very few people go on to develop CKD, and if they do, it usually takes decades and is often mild.
• Increased sensitivity to kidney injury: There is greater vulnerability to blunt trauma or injury to the remaining kidney.
• Uncommon issues: A small number of people report persistent fatigue or pain following surgical removal of a kidney, but this is rare.

How Significant Are These Risks?

Precautions and Recommended Follow-Up Care

Anyone with one kidney—regardless of the reason—should take certain precautions to protect long-term kidney health.

• Regular check-ups: See your healthcare provider at least once a year for blood pressure monitoring, urine analysis, and kidney function tests.
• Blood pressure management: Monitor your blood pressure regularly, as hypertension can impact kidney health.
• Urine testing: Annual urine tests for protein or blood can help detect early signs of kidney stress or damage.
• Kidney function tests: Blood tests such as eGFR (estimated glomerular filtration rate) are vital to assess how well your kidney is working.
• Blood sugar monitoring: For people at risk of, or living with, diabetes, good blood sugar control helps protect the single kidney.

Specific Lifestyle Adjustments

• Healthy diet: Eat a balanced diet rich in fruits, vegetables, whole grains, and lean proteins. If you have signs of kidney stress or proteinuria, your doctor may advise limiting your protein intake.
• Stay hydrated: Drink enough fluids, especially water, unless directed by your doctor to limit fluid intake.
• Maintain a healthy weight: Managing your body weight reduces the risk of hypertension and diabetes, both of which can affect kidney health.
• Limit salt intake: Salt raises blood pressure, which may stress your single kidney over time.
• Use caution with medications: Some over-the-counter painkillers (NSAIDs) and certain prescription drugs can be hard on your kidney. Always consult your doctor before starting new medications.
• Avoid unnecessary supplements: Do not take excess herbal or high-dose vitamin supplements without medical advice.
• Exercise regularly: Physical activity helps maintain overall health, including kidney health.
• Stay up-to-date with vaccinations: Infections such as influenza or COVID-19 can stress the kidneys, so proper immunizations are recommended.
• Protect the kidney: If you participate in contact sports, consider wearing protective gear such as a padded kidney guard and discuss risks with your healthcare provider.

Signs and Symptoms to Watch For

Most people with one healthy kidney do not experience symptoms of kidney problems. However, certain signs should prompt you to seek medical advice:

• Swelling of the face, hands, feet, or ankles
• Changes in urination (frequency, color, or appearance, such as foamy urine)
• Blood in urine
• Nausea or vomiting
• Unexplained fatigue or weakness
• Loss of appetite or metallic taste in the mouth
• Difficulty concentrating
• Shortness of breath with minimal exertion

If you experience any of these symptoms, consult your healthcare provider promptly for further evaluation.

Monitoring Kidney Health: Recommended Tests

• Urine test (urinalysis): Checks for blood, protein, and other markers of kidney health.
• Blood tests: Such as eGFR to measure kidney filtering ability, and blood urea nitrogen (BUN) or creatinine.
• Blood pressure: High blood pressure is both a cause and a consequence of kidney issues; monitor at least annually.
• Imaging tests: Ultrasound or CT scans may be used if structural evaluation is necessary.

Physical Activities, Sports, and One Kidney

Physical exercise is generally recommended and safe for those with one healthy kidney. However, certain contact sports place the single kidney at risk due to the potential for trauma. It is important to:

• Discuss all athletic activities with your doctor.
• Use protective sports equipment (such as padded vests) when participating in high-contact sports like football or hockey.
• Consider low-impact or non-contact sports, such as swimming, cycling, or running, when feasible.

Special Considerations for Children and Adolescents

• Children born with a single kidney or who lose a kidney often grow and develop normally.
• Follow the same healthy lifestyle and monitoring recommendations as adults.
• Consult a pediatric nephrologist for specialized care, as appropriate.

Pregnancy With One Kidney

Most women who have one kidney—and whose remaining kidney is healthy—can become pregnant and have successful pregnancies. However, pregnancy does place additional demands on the kidneys, so:

• Consult your doctor before conception to make sure your kidney is healthy enough for pregnancy.
• Regular monitoring during pregnancy is essential to ensure both mother and baby remain healthy.
• Doctors may recommend more frequent urine and blood pressure checks during gestation.

Kidney Donation: What To Expect

Many people who live with one kidney are former donors. Modern surgical and monitoring techniques have made kidney donation very safe. Most people return to their normal activities, with no long-term adverse effects on health.

• Long-term studies show that living kidney donors have lifespans similar to the general population.
• There is a very low risk (less than 0.5%) of developing significant kidney disease in the remaining kidney after donation.
• Routine health checks are especially important for kidney donors, as early detection of potential issues ensures prompt intervention.
• Uncommon complications after donation may include fatigue or discomfort, but these are rare and are often temporary.

FAQs About Living With One Kidney

Can I live a normal life with one kidney?

Yes, most people with one healthy kidney live normal, fulfilling lives and often do not experience any symptoms or reduction in life expectancy.

Will my remaining kidney grow or adapt?

The remaining kidney often grows larger and increases its function to compensate for the missing kidney, typically performing up to 70-80% of the work of two kidneys.

Are there foods I should avoid if I have one kidney?

For most people with normal kidney function, there are no strict dietary restrictions. However, if protein in the urine or reduced kidney function is detected, your doctor may recommend limiting dietary protein and salt.

Can I exercise and play sports?

Most physical activities are safe, but you should use protective gear during contact sports and discuss your exercise plans with your healthcare provider.

Should I take special precautions with medication?

Yes. Avoid non-steroidal anti-inflammatory drugs (NSAIDs) and consult your doctor before starting any new prescriptions or supplements, as some substances can put extra strain on your kidney.

Do I need to see a kidney specialist?

Most people with one healthy kidney can be monitored by their primary care provider with annual tests. If there are any abnormalities in kidney function or urine testing, referral to a specialist (nephrologist) may be appropriate.

Summary: Long-Term Outlook

Living with one kidney is not only possible but common and generally safe. With regular monitoring, healthy lifestyle choices, and attention to risk factors, most people continue to live long, active, and healthy lives. If you have one kidney, consistent follow-up with your healthcare provider is the best way to ensure your long-term health.