How Do I Prepare for My 1-Hour Glucose Test?

The 1-hour glucose tolerance test assesses your body's response to sugar (glucose). Learn how to prepare for the two main types of glucose tolerance tests

The glucose challenge test, sometimes referred to as the 1-hour glucose tolerance test, assesses your body's response to sugar (glucose). How you prepare for the 1-hour glucose test depends on which type has been requested by your physician.

If you are unsure about which test you need to prepare for, ask your doctor. They will inform you of the screening procedure and whether there are specific instructions you must follow to ensure that the findings of the tests are accurate.

How to prepare for the 2-step glucose test

1. Glucose screening test:
   1. You are not required to change your diet before this step.
   2. You will be required to consume a glucose-containing beverage.
   3. Your blood will be taken 1 hour after you consume the glucose solution to determine your blood glucose level.
   4. This step will determine whether your blood glucose level is high or normal.
2. If your glucose level is too high, you will be required to return for a 3-hour glucose tolerance test:
   1. For 8-14 hours before this test, you must refrain from eating or drinking anything (except a few sips of water). 
   2. You will be required to consume 100 grams of a glucose-containing beverage. A blood sample will be taken before you drink the beverage and then once every hour after you have finished drinking it. Each time, your blood glucose level will be measured.
   3. This process will take at least 3 hours.

How to prepare for the 1-step glucose test

You will need to visit the lab just once for the 1-step glucose test and the process will last 2 hours. For this process, the following things are required:

• For 8-14 hours before your test, you must refrain from eating or drinking anything (except a few sips of water). 
• You will be required to consume 75 grams of a glucose-containing beverage. A blood sample will be taken before you drink the beverage and then once an hour after you have finished drinking it. Each time, your blood glucose level will be measured.
• This process will take at least 2 hours.

What is the 1-hour glucose test used for?

One of the most common uses of the 1-hour glucose test is the diagnosis of diabetes during pregnancy (gestational diabetes), which can be dangerous for both the mother and baby. 

If you have been diagnosed with gestational diabetes, a dietitian can help you create a personalized nutrition plan. You will need to reduce your consumption of sugar and refined carbs and increase your consumption of fruits, vegetables, lean protein, healthy fats, and a modest quantity of complex carbohydrates, such as whole grains, sweet potatoes, and starchy vegetables.