how long do you fast for a diabetes test

For a fasting blood glucose test, which is commonly used to diagnose diabetes or prediabetes, you typically need to fast for 8 to 12 hours before the test. This means no food or drink (except water) during this period. Fasting ensures accurate measurement of your blood sugar levels without the influence of recent meals.

However, for an A1C test, fasting is not required because it measures your average blood sugar levels over the past 2-3 months and is not affected by recent food intake.