What Is Time in Range and Why It Matters More Than A1C

If you only track A1C, you're missing half the picture. Time in Range (TIR) — the percentage of time your blood sugar stays between 70 and 180 mg/dL — has emerged as the most important metric in modern diabetes management. A person can have an A1C of 7.0% while spending hours in dangerous highs and lows that an A1C simply averages away.

What the Research Shows

The American Diabetes Association now recommends a TIR goal of over 70% for most adults with diabetes. Studies show that every 10% increase in TIR reduces the risk of diabetic kidney disease by 40% and reduces A1C by approximately 0.8 points. CGM sensors like the Dexcom G7 and FreeStyle Libre 3 make TIR tracking effortless.

For the complete guide to Time in Range targets, how to improve your TIR, and which CGM devices track it best, visit the MDS Diabetes Encyclopedia.