eGFR (Combined)
eGFR (average) combines the creatinine-based and cystatin C-based estimates of how well the kidneys filter the blood.
eGFR (average) combines the creatinine-based and cystatin C-based estimates of how well the kidneys filter the blood. Each method has its own sources of variation, and taking both together evens these out. The result is a steadier read on kidney filtration. Retesting shows how it changes over time.
Hydration on the day of the test, hard training in the days before, a large meat-rich meal shortly before the sample and some medicines can all shift the value. Filtration also changes gradually with age. Muscle mass and diet matter less here than for the creatinine-based estimate alone.
Foods that help
Water through the day, plenty of vegetables, fruit, legumes and whole grains, and a balanced protein intake from both plant and animal sources.
Foods to limit
Very salty and ultra-processed food, and large amounts of meat shortly before the test.
Track it through the year
One value is a snapshot. Following it up shows whether what you changed is working.
Related markers
Educational information only — not a diagnosis. Every result is checked against safe limits, and anything critical is escalated for follow-up.
See all 84 markers →