You don't need to fast before all blood tests. Your doctor will tell you if you need to. These tests typically require fasting: Fasting blood glucose measures the amount of glucose (sugar) in your blood to test for diabetes or prediabetes.
Is a full blood count test fasting?
You can eat and drink as normal before some blood tests. But if you're having a "fasting blood test", you will be told not to eat or drink anything (other than water) beforehand. You may also be told not to smoke before your test.
What blood tests require fasting?
Blood tests that you will likely need to fast for include:
- blood glucose test.
- liver function test.
- cholesterol test.
- triglyceride level test.
- high-density lipoprotein (HDL) level test.
- low-density lipoprotein (LDL) level test.
- basic metabolic panel.
- renal function panel.
