How long to fast for A1C test?

A1c test

Sharing Experience: This is something very important, because most people still think that they have to fast, before the A1C test.

However, this statement is not true and you don’t have to fast.

In purpose to understand why, you have to know that the A1C value represents your blood glucose concentration during the past 2-3 months.


That means that having high or low blood glucose at the day of the test, will not lead to severe changes in your A1C result.

Something which you have to know is that A1C test is executed along with blood glucose test and blood cholesterol test.

It is important for you to know this, because those tests mentioned above have to be executed, while you are hungry.

So, in purpose to be sure that you will not make something wrong by eating regularly the morning before the tests, speak with your physicians about the test, which he/she wants.

If your physician tells you that he wants blood glucose or blood cholesterol test along with the A1C test you have to fast at least for 10 hours.

Besides this, I want to inform you that if you want to have normal A1C test result, which is less than 7%, you have to keep your blood glucose level within the normal ranges.

I’m sure that you know them, but you just have to follow them as well.


Dr's Response

Yes, it's true that A1C testing does not require any fasting. You can eat normally and take the test at any time of the day.

A1C test measures your average blood sugar levels over the past two to three months, so there is no need to fast before the test.

However, if you are taking any medication for diabetes, your healthcare provider may recommend that you take the medication after the test to get an accurate reading.

It's always best to follow your healthcare provider's instructions regarding any test or procedure.

More information on a1c test and levels