Kidney health
Estimated glomerular filtration rate (eGFR)
Included in every MyHealthspan membership: Focus, Baseline, and Complete.
Compare membershipsAn estimate of how well your kidneys filter.
eGFR estimates how much blood your kidneys filter each minute. It's calculated from your creatinine result along with factors like your age and sex, and it's a key measure clinicians use to assess kidney function.
eGFR is an estimate, so context matters.
Because eGFR is calculated from creatinine, anything that shifts creatinine shifts eGFR too. Very high or low muscle mass, creatine supplements, hard exercise, and a large meat meal can all make the estimate less accurate.
eGFR also tends to decline gradually with age, even in healthy kidneys. A single low result doesn't confirm kidney disease. Guidelines look for changes that last at least three months, and a cystatin C test can help confirm the estimate when creatinine may be misleading.
One eGFR is a snapshot. The trend tells the story.
Questions
What does a lower eGFR mean?
A lower eGFR may suggest your kidneys are filtering less efficiently. Your clinician will consider your age, earlier results, blood pressure, blood sugar, medications, and urine tests before drawing conclusions, and may repeat the test.
Why is eGFR calculated instead of measured?
Measuring filtration directly takes a specialized test. Labs instead estimate it from a blood marker using a validated equation, which makes it easy to track over time.
Where can I see my eGFR and what it means?
Your results appear in the MyHealthspan app, where the AI health assistant can help explain eGFR alongside your creatinine and other results. From there, your clinician can decide whether repeat testing or follow-up makes sense.