Reading Your Blood Sugar Results

Doctors use three common tests to check for prediabetes. Each one measures blood sugar in a different way.

The fasting blood sugar test needs at least eight hours with no food. The A1C test is a simple blood draw, and no fasting is needed.

The OGTT, or oral glucose tolerance test, is the third test. It starts with a measured sugar drink.

Blood is then drawn at intervals over about two hours. The test shows how your blood sugar looks two hours after the drink.

One result is a useful clue, but it is not always the final answer. Stress, illness, some medicines, or a heavy meal the night before can raise fasting results. That effect can last for a time.

So doctors often repeat a high result or confirm it with a second test.

Key takeaways

• Three common tests check for prediabetes: fasting, A1C and OGTT.
• Each test measures blood sugar in its own way and at its own time.
• A single result is useful, and doctors often confirm it with a repeat test.

Try it

Look at your latest lab slip, find which of the three tests it was, and note the date.