If you have type 2 diabetes and your red blood cells don’t live as long, your actual blood sugar might be higher than what your A1c test shows — meaning the A1c test could be misleading for some...

If you have type 2 diabetes and your red blood cells don’t live as long—less than 75 days—your A1c test might not give a true picture of your blood sugar control, because the test could show lower numbers than reality.

If someone with type 2 diabetes has red blood cells that don't live as long as usual, their A1c test might show better blood sugar control than they actually have — meaning doctors could miss signs of high blood sugar over time.

Even when blood sugar averages look good on a diabetes test, people with shorter-lived red blood cells might still have higher actual sugar levels throughout the day.

If someone with type 2 diabetes has good HbA1c numbers but their red blood cells don’t live as long, their blood sugar might actually be higher than the test shows — meaning the test could be giving them a too-rosy picture of their sugar control.

If you have type 2 diabetes, higher blood sugar might make your red blood cells die faster, which could mess up the accuracy of your A1c test — a common way doctors check long-term blood sugar control.