What should i not eat the night before my glucose test

• What Is It?
  • What is an oral glucose tolerance test?
• Procedure
  • How is an oral glucose tolerance test performed?
• Side Effects
  • Are there side effects of the oral glucose tolerance test?
• Related Resources
  • Related Resources - What Should I Eat the Day Before My 3-Hour Glucose Test?

For three days before your glucose test, you can consume about 150 grams or 10 servings of carbohydrates.

For about three days before the test, you can eat about 150 grams or 10 servings of carbohydrates. These should be taken over the whole day.

One serving of carbohydrate

• One slice of bread = Half a large bread roll or muffin
• One-fourth Lebanese bread
• One apple = One orange = One small banana
• Medium mandarin = Two peach = Three apricots = Three prunes
• Two Weetabix
• One-fourth cup muesli = One-third cup Just Right = Half cup bran flakes (most people would have two to three servings of cereal for a meal)
• Three-fourth cup cornflakes (most people would have two servings of cornflakes for a meal, that is, a bowlful is about one and a half cups)
• Two biscuits (milk coffee, shredded wheat, and full-o-fruit)
• One cup milk
• One 200-gram carton of yogurt
• Half cup cooked pasta (most people would have 1 to 1.5 cups of pasta for a meal, which would be two to three servings)
• One-third cup cooked rice (most people would have two-thirds to one cup of rice for a meal which would be two to three servings)
• One medium potato
• One small corn cob

You can consume some extra fruit juice or biscuits instead of bread and cereals. Include meat, fish, eggs, cheese, butter, and margarine during these three days.

Do not eat or drink anything after 10 on the night before the test. Refrain from smoking after 9 the night before the test.

How is an oral glucose tolerance test performed?

You will fast for 8 to 10 hours before the test starts.

The test procedure is performed in the following manner:

• The nurse collects an initial baseline blood sample.
• You will be given a glucose drink with 75 grams of glucose, which should be consumed within five minutes.
• Further blood samples are collected every 60 minutes.
• Your blood glucose level will be tested one, two, and three hours after drinking the solution.
• Once the test ends, you should have something to eat and drink (it is best to take it with you).

Are there side effects of the oral glucose tolerance test?

The oral glucose tolerance test does not cause any serious side effects. Some people may have side effects from sugary drinks or blood tests.

Side effects due to sugary drinks may include:

• Nausea
• Vomiting
• Bloating
• Headache

Side effects of blood tests may include:

• Excess bleeding
• Bruising
• Fainting
• Infection due to improper handling of vein
• Issues with finding a vein

QUESTION

Medically Reviewed on 4/14/2022

References

Image Source: iStock Image

https://www.webmd.com/diabetes/guide/oral-glucose-tolerance-test

https://www.mayoclinic.org/tests-procedures/glucose-tolerance-test/about/pac-20394296

The purpose of the oral glucose tolerance test is to measure the body’s ability to use a type of sugar, called glucose. Glucose is the body’s main source of energy. An OGTT can be used to diagnose prediabetes and diabetes. An OGTT is most commonly done to check for diabetes that occurs with pregnancy, called gestational diabetes.

How To Prepare – 1 hour test

1. Eat a meal low in carbohydrates before this test. Example of foods to eat for breakfast would be eggs, cheese, bacon and or sausage. Avoid breads, cereals and fruit juices. Example of foods for lunch would be lettuce/salad with any kind of meat. Green beans, broccoli and any leafy vegetable. Avoid fried foods, no bread, soft drinks with sugar or sweet tea.
2. 1 1/2 – 2 hours after eating, drink the entire 59 gram glucola drink.
3. Be at the office 30 minutes after finishing the cola. This is to insure that you are at the clinic on time for your blood work which will be drawn 1 hour after drinking the cola.
4. When you check in at the fron desk, be sure and tell the receptionist what time you finished drinking the cola.

How to Prepare – 3 hour test

If your doctor would like to see additional testing, based on your results from the 1 hour test, you may be asked to have a 3 hour OGTT. It is important to follow all of the instructions very carefully, as it will affect the results of the test.

When you arrive at the office a sample or baseline glucose test will be run and used for comparing other glucose values. You will be asked to drink a sweet liquid containing a measured amount of glucose, it is best to drink it quickly. Then blood samples will be collected at timed intervals of 1,2, and 3 hours after you drink the glucose.

Here is the best method of preparation:

1. Eat a balanced diet that contains at least 150 grams of carbohydrates per day for 3 days before the test. Fruits, breads, cereal, rice, crackers, and starchy vegetables such as potatoes, beans and corn are good sources of carbohydrates.
2. Do not eat, drink, smoke, or exercise strenuously for at least 8 hours before your first blood sample is taken.
3. Tell your doctor about all prescription and nonprescription medicines you are taking. You may be instructed to stop taking certain medicines before the test.
4. The OGTT may take up to 4 hours. Since activity can interfere with test results, you will be asked to sit quietly during the entire test. Do not eat during the test. You may drink only water during this time.

What should I eat the day before my glucose tolerance test?

What should I not do before my glucose test?