Artículo
Análisis de sangre: la eGFR
La filtración glomerular estimada (eGFR) es un estimador de qué tan bien funcionan los riñones.
- Revisión médica de
- AKF's Medical Advisory Committee
- Última actualización
- October 23, 2026
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What is eGFR?
eGFR (estimated glomerular filtration rate) is a measure of how well your kidneys are working. Your eGFR is an estimated number based on a blood test and your age and sex.
eGFR is considered a mostly reliable test for doctors to know how well your kidneys are working. However, the eGFR may not be accurate if you are younger than 18, pregnant, very overweight or very muscular. In addition, other tests such as an ultrasound or a kidney biopsy may be ordered to find a cause of your kidney disease.
Previously, Black race was used in the eGFR calculation along with age and sex. However, in 2021, a task force led by the National Kidney Foundation (NKF) and the American Society of Nephrology (ASN) announced recommendations to remove Black race as a factor in the eGFR calculation. The new recommended equation estimates kidney function using creatinine, age and sex without adjusting the result based on whether a person is Black. Labs and health systems have been changing to race-free eGFR equations since this recommendation, but you should check with your doctor to make sure they are not using race-based equations. Learn more.
The eGFR equation also uses a binary definition of gender. If you are a transgender or gender-diverse person, talk to your doctor about how you can get the best estimate of how well your kidneys are working.
How accurate are eGFR results?
eGFR is an estimate of how well your kidneys filter waste from your blood. While it gives doctors useful information about how well your kidneys are working, it is not a direct measurement of kidney function.
Most eGFR tests use the amount of creatinine (a waste product made by your muscles) in your blood. Creatinine comes from normal muscle activity, so other factors can affect your eGFR result, including very high or very low muscle mass, pregnancy, eating certain foods, and taking certain supplements or medicines.
One eGFR result does not always tell the full story. Your doctor may look at how your eGFR changes over time and use other tests, such as a urine albumin test (uACR), to better understand your kidney health.
How do I find out my eGFR?
You will have a blood test to see how much creatinine is in your blood. Creatinine is a waste product in your blood that comes from your muscles. Healthy kidneys take creatinine out of your blood and send it out of your body through your urine. If your kidneys are not working the way they should, creatinine will build up in your blood.
The eGFR test report will give a number that will tell doctors the amount of creatinine in your blood. You will also get a lab report that will contain this number. Be sure to talk to your doctor about what your results mean for you.
Can my eGFR change?
Your eGFR can change over time and can change based on some other problems, like if you have not been drinking enough water. Kidney function also tends to decrease as you get older, even if you do not have kidney disease. Your doctor will look at your age, other kidney test results and how your eGFR changes over time to understand what your number means for you. As chronic kidney disease gets worse, your eGFR number will go down. If caught early, healthy lifestyle changes like following a kidney-friendly eating plan and getting enough exercise may help slow down the progression of chronic kidney disease (CKD) and how fast your eGFR changes.
Can I have kidney disease even if my eGFR is normal?
Yes, your eGFR may still be in the normal range even if you have some signs of kidney damage, such as proteinuria or protein in your urine (pee) or physical damage to your kidneys. If you have protein in your urine, your doctor will check you again to make sure it is not caused by something else, like being dehydrated. Your doctor may also order a uACR test. This test checks for albumin, a type of protein, in your urine. Albumin in your urine can be a sign of kidney damage even when your eGFR is 60 or higher, so it is important to get both tests done regularly.
Do I need to do anything to prepare for my eGFR test?
Your doctor may have you fast (not eat or drink) or avoid certain foods for several hours before the test. They will let you know how to prepare.
You may have a blood creatinine test as part of a regular check-up or if your doctor thinks you might have kidney disease. Your doctor will figure out your eGFR using your creatinine blood test result and your age, sex and weight. The recommended eGFR equation no longer includes race.
What does my eGFR mean?
Your eGFR result helps show how well your kidneys are filtering your blood, but one number alone usually cannot diagnose chronic kidney disease. Doctors also consider whether your eGFR stays low over time and whether you have other signs of kidney damage, such as albumin or protein in your urine.
Your eGFR is only one part of understanding your kidney health. An eGFR that remains below 60 for three months or longer may mean you have CKD, but an eGFR of 60 or more doesn't rule it out. Your doctor will look at your eGFR, urine test results and other health information to understand what your results mean for you.
Use this chart to find out what your eGFR test result may mean
| Your eGFR number | What does it mean? |
| 60 or above | Your kidneys may be working well. If you have other signs of kidney damage, such as protein in your urine, you may still have kidney disease. |
| Under 60 | If your eGFR stays below 60 for 3 months or more, you may have kidney disease. |
| Under 15 | Your kidneys may be close to failure or have failed. You may need dialysis or a kidney transplant. |
Stage 1 CKD
eGFR: 90 or higher
At stage 1 CKD, your kidneys are still filtering your blood well, but there are other signs of kidney damage. Even if your eGFR is in a normal range (60 or above), protein in your urine can be a sign of early kidney damage.
What can you do?
Talk to your doctor about ways you can slow down the damage to your kidneys.Follow your treatment plan and keep up with your kidney tests so your care team can watch for changes.
Stage 2 CKD
eGFR: 60–89
At stage 2 CKD, your kidneys have a mild decrease in how well they filter your blood. This means your kidneys' ability to filter waste from your blood is mildly decreased. Even if your eGFR is in a normal range (60 or above), protein in your urine can be a sign of early kidney damage.
What can you do?
Work with your doctor to manage conditions that can affect your kidneys and follow your treatment plan. Regular kidney tests can help your care team see whether your kidney function is changing over time. Talk to your doctor about ways you can slow down the damage to your kidneys.
Stage 3 CKD
eGFR: 30–59
At stage 3 of CKD, your kidneys are not working as well as they should. Your kidneys may have mild to moderate damage.
Stage 3 is separated into two stages:
- Stage 3a: eGFR between 45 and 59
- Stage 3b: eGFR between 30 and 44
What can you do?
Talk with your doctor about ways to slow kidney damage and lower your risk of other health problems. This may include taking medicines as prescribed, managing conditions such as diabetes or high blood pressure and making healthy lifestyle changes. Ask for a referral to a nephrologist (kidney doctor) if you do not already have one.
Sample eGFR test results
Stage 4 CKD
eGFR: 15–29
At stage 4 CKD, your kidneys have a severe decrease in how well they filter your blood. You have a higher risk of developing kidney failure and other health problems related to CKD. Your kidneys are still working, but not as well and may be close to failing.
What can you do?
Work closely with your nephrologist to protect the kidney function you have left. Your care team may also begin talking with you about treatment options if your kidneys stop working well enough to keep you healthy, including dialysis and kidney transplant.
Stage 5 CKD
eGFR: Less than 15
Stage 5 CKD is also called kidney failure or end-stage kidney disease (ESKD). At this stage, your kidneys have lost most of their ability to filter waste and extra fluid from your blood. At this stage, your kidneys may be close to failure or have stopped working. If your kidneys fail, waste builds up in your blood, which makes you very sick.
What can you do?
Once your kidneys have failed, you will need to start dialysis or have a kidney transplant to live. Talk to your nephrologist (kidney doctor) about your treatment options.
No matter what your eGFR is, take these steps to keep your kidneys as healthy as possible
- Keep a healthy blood pressure (less than 120/80 for most people).
- Control your blood sugar if you have diabetes.
- Follow a healthy low-salt, low-saturated-fat eating plan.
- Do something active for at least 30 minutes most days of the week, such as walking or biking.
- Keep a weight your doctor says is healthy for you.
- Do not smoke or use tobacco.
- Ask your doctor about medicines that may help protect your kidneys.
No matter what your eGFR is, ask your doctor when you should be tested again and what other tests you should have.
Your doctor may want to do other tests to look for signs of kidney problems, such as:
- Urine test for protein or blood
- Blood test for other wastes
- Blood pressure
- Blood sugar (glucose) test
Questions to ask your doctor about your eGFR test result
- What does my eGFR result mean for me?
- How has my eGFR changed over time?
- Should my eGFR be tested again? If so, when?
- Should I have a uACR or other kidney test?
- Could any of my medicines or supplements affect my kidney function and creatinine levels?
- Do I need to change any of my medicines based on my kidney function?
- Would a cystatin C test help give a more accurate estimate of my kidney function?
- Do I need to see a kidney doctor?
How can I improve my creatinine and eGFR levels?
There is no single food, drink or supplement that can raise your eGFR. Some things, like dehydration, muscle mass and medicine, can temporarily affect your eGFR result, but these changes do not always mean that your kidney disease has gotten better or worse.
To help protect your kidney health:
- Drink the amount of fluid your doctor recommends. Some people with kidney or heart problems may need to limit fluids.
- Follow an eating plan that is right for your kidney health.
- Keep your blood pressure and blood sugar within the goals you and your doctor have set.
- Tell your doctor about all prescription medicines, over-the-counter medicines, vitamins and supplements you take.
- Do not stop taking medicines or make major changes to your diet or fluid intake to change your eGFR number without talking to your doctor first.
If your eGFR has changed
Ask your doctor whether you should repeat the test and whether another test, such as a uACR or cystatin C blood test, could provide more information.
While no specific food or supplement can single-handedly improve kidney function or creatinine levels, Kidney Kitchen® contributor, Dr. Blake aka "The Cooking Doc®," explains what factors can affect those readings - and tips to potentially improve them!
Learn about improving your creatinine and eGFR levels.
Encuentre deliciosas recetas nefrosaludables
Infórmese sobre la importancia de la alimentación saludable para las personas en cualquier etapa de la enfermedad renal, incluidas las que reciben diálisis o son portadoras de un trasplante renal.
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