Which test is primarily used for confirming diabetes diagnosis?

The glucose tolerance test is conducted to assess how effectively the body processes glucose. It involves taking a fasting blood sample, followed by the ingestion of a glucose solution, and measuring blood glucose levels at intervals afterward. This test is particularly useful in diagnosing diabetes or prediabetes, as it evaluates the body's ability to regulate blood sugar levels over time after glucose intake.

While the glucose tolerance test is an important diagnostic tool, it is not the primary confirmation test for diabetes diagnosis. The A1C test is widely regarded as the standard for diagnosing diabetes because it reflects average blood glucose levels over the past two to three months. It provides a clear picture of long-term glucose control and is less influenced by immediate changes in diet or exercise. Therefore, the A1C test is often preferred as it is more convenient and requires no special preparation compared to other tests.