Kidney Function (eGFR, Cystatin C)
Estimated glomerular filtration rate (eGFR) in ml/min/1.73m2, the standard measure of kidney filtering capacity. Optimal range: eGFR 90 and above is normal/high (KDIGO G1); below 60 persisting 3 months defines chronic kidney disease.
What it measures
Estimated glomerular filtration rate (eGFR) in ml/min/1.73m2, the standard measure of kidney filtering capacity. Cystatin C is a muscle-independent marker that refines the estimate.
Why it matters
Kidney function declines with age and is a major determinant of healthspan: poor filtration raises cardiovascular risk, drug toxicity, and frailty. Creatinine-based eGFR overestimates function in muscular people and underestimates it in frail ones, so cystatin C adds precision.
Optimal ranges
Sourced targets, not just lab reference ranges. Lab ranges describe the population; these describe where the evidence says you want to be.
| Range | Context |
|---|---|
| eGFR 90 and above is normal/high (KDIGO G1); below 60 persisting 3 months defines chronic kidney disease | KDIGO GFR categories; use a combined creatinine plus cystatin C equation when muscle mass is unusually high or low. |
How to improve it
- 1
Control blood pressure and blood sugar, the top kidney threats
- 2
Stay hydrated, avoid chronic NSAID use
- 3
Limit excess sodium and protein extremes
- 4
Maintain healthy weight
Connected to
Goals
Longevity Lab Report
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Educational information, not medical advice. Talk to your doctor before acting on any biomarker result.