Cystatin C

Cystatin C is a protein made by all cells and filtered by your kidneys—making it a highly sensitive marker for kidney function and early-stage decline. Unlike creatinine, it’s less affected by muscle mass, so it's often more accurate for biohackers, athletes, and lean individuals. Elevated levels may point to reduced filtration, chronic inflammation, or cardiovascular risk, even when other kidney markers look normal. Great for tracking cellular cleanup, filtration efficiency, and longevity risk.

Unit

mg/L

Health impacts

Metabolic Health