Understanding Your A1c
The Hemoglobin A1c is a simple blood test that shows your average blood sugar over the past two to three months. It is the main test used to screen for and monitor diabetes.
What A1c Measures
Sugar in your blood attaches to hemoglobin, the protein inside your red blood cells. The A1c measures the percentage of your hemoglobin that is coated with sugar.
Because red blood cells live about three months, the A1c reflects your average blood sugar over that time, not just the day of your test. You do not need to fast for it.
What Your Results Mean
| A1c Level | What It Means |
|---|---|
| Below 5.7%Normal | Your average blood sugar is in the healthy range. |
| 5.7% to 6.4%Prediabetes | Your blood sugar is higher than normal. This is a warning stage where lifestyle changes can often prevent diabetes. |
| 6.5% or higherDiabetes | This level, usually confirmed on a repeat test, indicates diabetes. |
Why It Matters
Catching high blood sugar early, especially at the prediabetes stage, gives you the best chance to turn things around with diet, activity, and, if needed, medication. If you already have diabetes, the A1c helps us see how well your management plan is working over time.
What’s Most Important to Know
A single A1c is a snapshot of a trend. We look at how it changes over time and alongside your other health factors.
Certain conditions, like anemia or recent blood loss, can affect A1c accuracy. If your result is surprising, Dr. Mui may recommend a repeat or an additional blood sugar test.
This page is for general education and does not replace a conversation with your doctor about your specific results. Want to review your results? Book a visit and we’ll go through them together.