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Your provider has asked that you have a blood test(s) that requires you to be fasting before the blood draw.
Common tests that require fasting are:
Fasting Glucose (8+ hours)
Tolerance Test* (8+ hours)
Lipid Panel, Fasting (10+ hours)
*Fasting is not required for 1-hour glucose challenge for gestational diabetes.
If your test is not listed above, we recommend that you fast for 10 hours.
Fasting means you don’t eat or drink anything but water for a period of time before the blood draw.
You also shouldn’t smoke, chew gum (even sugarless) or exercise. These things can affect your digestion, which can affect your test results.
Take your prescription medicines unless your doctor tells you to skip them. Ask your provider before you take over-the-counter drugs.
Why is Fasting Done?
Nutrients in food and drinks go into your bloodstream and can change things measured by tests, which will affect your test results. Fasting makes sure the results from the test are correct.
What if I Forget?
If you make a mistake and eat or drink something besides water, please tell the person drawing your blood. Your provider may change your test orders so your blood can be drawn and they can read those tests correctly. For best test results, they may ask you to return when you are fasting.
After the Blood Draw
Once the blood has been drawn, the fast is over! Please feel free to bring a snack and drink with you to your lab visit so you can eat as soon as you can after the blood draw.