Your Kidney Filtration Score
eGFR estimates how many milliliters of blood your kidneys filter per minute. Think of it as a performance rating for your kidneys. A score above 90 means excellent filtration. Below 60 means chronic kidney disease. Below 15 means kidney failure.
What is Estimated GFR?
eGFR is calculated from creatinine (or cystatin C), age, and sex. It's the primary metric for diagnosing and staging chronic kidney disease (CKD): Stage 1 (>90), Stage 2 (60-89), Stage 3 (30-59), Stage 4 (15-29), Stage 5 (<15).
↑ What High Estimated GFR Means
High eGFR (above 90) is normal and healthy. Very high values can sometimes be seen in early diabetes or pregnancy.
Common symptoms:
Not typically concerning
↓ What Low Estimated GFR Means
Your kidneys are filtering blood less efficiently than they should. The lower the number, the more advanced the kidney impairment.
Common symptoms:
Often asymptomatic until advanced · Fatigue · Swelling in legs and ankles · Foamy urine · Decreased urine output · Nausea · Itching · Muscle cramps
Why It Matters
When normal:
Gold standard for kidney function assessment
Stages chronic kidney disease
Guides medication dosing
Determines dialysis need
Risks if abnormal:
eGFR 60-89: mild reduction, monitor closely
eGFR 30-59: moderate CKD, active management needed
eGFR 15-29: severe CKD, prepare for dialysis/transplant
eGFR <15: kidney failure
What Can Cause Abnormal Levels?
Diabetes (Diabetic Nephropathy)
45% likelyThe #1 cause of kidney disease worldwide. High blood sugar damages tiny kidney blood vessels over years.
High Blood Pressure
40% likelyThe #2 cause. Chronic hypertension damages kidney blood vessels and reduces filtration.
Aging
GFR naturally declines ~1 mL/min/year after age 40. Mild reduction in elderly is often normal.
NSAIDs and Nephrotoxic Drugs
Regular ibuprofen, naproxen, or certain antibiotics can damage kidneys over time.
Dehydration
Can temporarily reduce GFR by reducing blood flow to kidneys.
What You Can Do
Control blood pressure: target <130/80
Impact: Single most important kidney protection \u00B7 Timeline: Ongoing
Control blood sugar if diabetic: HbA1c <7%
Impact: Slows diabetic kidney damage \u00B7 Timeline: Ongoing
Stay hydrated: 2-3L water daily
Impact: Supports kidney blood flow \u00B7 Timeline: Ongoing
Limit NSAID use (ibuprofen, naproxen)
Impact: Removes direct kidney toxin \u00B7 Timeline: Immediate
If lifestyle changes aren't enough:
Moderate protein intake: 0.8g per kg if CKD stage 3+
Impact: Reduces kidney workload \u00B7 Timeline: Ongoing
Reduce sodium to <2g/day
Impact: Lowers blood pressure and kidney stress \u00B7 Timeline: 2-4 weeks
Regular exercise
Impact: Improves blood pressure and metabolic health \u00B7 Timeline: 4-8 weeks
Recommended retest: 3-6 months; more frequently if declining
Got your blood test report?
Upload your PDF and understand ALL your markers in 2 minutes. Plain language. Traffic light status. No medical jargon.
Analyze My Report — FreeFirst report is free. No credit card needed.