HBA1C vs Time in Range: Which is better?

When it comes to tracking diabetes, two key numbers often come up, HbA1c and Time in Range (TIR). Both provide useful insights and are somewhat related, but which one gives a better picture of your health? Let’s take a closer look.

HbA1c measures your average blood sugar over the past 2-3 months. It works by tracking how much glucose attaches to hemoglobin in red blood cells. Since these cells live for about three months, the percentage of glucose-attached hemoglobin gives an estimate of long-term glucose control.

Higher HbA1c levels are linked to an increased risk of complications. Every 1% rise in HbA1c raises the risk of diabetes-related problems by 14 to 20%.

TIR on the other hand measures the percentage of time your blood sugar stays within the normal range (70–180 mg/dL). This metric helps track how stable your glucose levels are throughout the day. Every 10% increase in TIR (about 2.4 extra hours in range per day) reduces the risk of microvascular complications by 30–40%.

Both metrics have their own strengths and weaknesses:

HbA1c is great for long-term trends and predicting diabetes complications, but it doesn’t show daily sugar swings. On the other hand, TIR shows real-time highs and lows, giving a clearer picture of glucose stability, but you need a CGM to track it properly.

Now even if your HbA1c is within the target range, frequent sugar spikes and drops can still cause problems. These fluctuations can lead to oxidative stress, inflammation, and faster organ damage. They can also affect your brain, causing irritability, anxiety, and trouble concentrating.

You can see that I am slightly leaning towards TIR here.

TIR provides a more comprehensive view of glycemic control. It helps you make real time adjustments taking corrective measures for high and low blood sugar levels. Studies have shown that increasing TIR can significantly reduce the risk of microvascular complications, such as retinopathy, neuropathy, and nephropathy.

But while TIR is helpful, HbA1c has been used widely for a long time and has stood the test of time. It is a well established metric and is used widely among diabetic professionals. Although different measures, both are very correlated.

The best approach? Use both HbA1c and TIR together. HbA1c will help track your long-term diabetes management, while TIR will give you a more detailed, day-to-day understanding of your glucose patterns. This way, you can get a full picture of your blood sugar control and take better steps to manage your health.

Gurucose platform provides both TIR and eHbA1c (calculated from your CGM data). It will help you manage your sugar levels on a daily basis. So if you haven’t already, download the Gurucose app from the App Store or Play Store and connect your CGM!