eGFR Thresholds: What They Mean for Your Kidneys

If you’ve ever seen a lab report with a number like 75 mL/min/1.73m², you’re looking at your estimated glomerular filtration rate (eGFR). It’s the doctor’s shortcut for how well your kidneys are filtering waste. Knowing the thresholds helps you spot early problems before they turn serious.

eGFR is calculated from your blood creatinine, age, sex and race. The result is an estimate of how many milliliters of blood your kidneys clean each minute per 1.73 m² body surface area. Higher numbers mean better filtration; lower numbers signal reduced function.

Common eGFR Ranges and Their Names

90 + mL/min/1.73m² – Normal: Your kidneys are working at full strength. Most healthy adults fall here, though athletes may see slightly higher values because of increased muscle mass.

60–89 mL/min/1.73m² – Mildly Decreased: Usually no symptoms yet. Doctors call this Stage 2 chronic kidney disease (CKD). Keep an eye on blood pressure and sugar, as they can push the number down.

30–59 mL/min/1.73m² – Moderate: This is Stage 3 CKD. You might start feeling fatigue or mild swelling. It’s a good time to review medications that strain the kidneys and discuss dietary changes.

15–29 mL/min/1.73m² – Severe: Stage 4 CKD. Waste builds up faster, and you may notice more pronounced symptoms like itching or loss of appetite. Specialist referral becomes essential.

Below 15 mL/min/1.73m² – Kidney Failure: Stage 5 CKD (end‑stage renal disease). Dialysis or transplant is usually required to keep you alive.

How to Use Your Lab Result

When you get your eGFR, first compare it to the ranges above. If you’re in the 60–89 bracket, ask your doctor why and whether lifestyle tweaks could improve it. For numbers under 60, schedule a follow‑up sooner rather than later – early intervention can slow progression.

Remember that eGFR isn’t static. It can swing with dehydration, new medications or changes in muscle mass. Re‑checking after a few weeks of stable health gives a clearer picture.

Factors like age (eGFR naturally drops about 1 mL/min/1.73m² per year after 40) and body composition affect the estimate. If you’re very muscular or frail, your eGFR might be misleading; ask for a cystatin‑C test if needed.

Practical steps to protect your kidneys: stay hydrated, keep blood pressure under 130/80 mmHg, control blood sugar, limit high‑protein and salty foods, avoid unnecessary NSAIDs, and quit smoking. Small changes add up and can keep your eGFR in the healthy zone longer.

Bottom line – eGFR thresholds are a quick health snapshot. Knowing where you fall helps you act early, talk confidently with your doctor, and take steps to preserve kidney function.