How long fasting blood test

Your diet contains a range of nutrients, including carbohydrates, proteins, fats, minerals and vitamins. When you eat and drink normally, those nutrients are broken down and absorbed into your bloodstream.

This can impact the levels of those substances in the blood and skew lab test results. The patient could be misdiagnosed with prediabetes or diabetes, unless their doctor recommends that they complete a second test. Not all lab tests require fasting beforehand, but many of the most common blood tests do. Tests that typically require fasting include:. Yes, you can drink water while fasting before a blood test—in fact, drinking plenty of water can help ensure that you receive accurate test results.

If you have one or more of these symptoms, your doctor may order a fasting lab test. If I need a fasting blood test, am I allowed to eat or drink anything? Why do I have to fast? When can I eat or drink after my lab test? When will I get the test results? The Importance of Lung Cancer Screenings. What to Look for in a Prenatal Breastfeeding Class. Tips for Coping with the Fall Time Change. A blood glucose test measures the amount of glucose in your blood. This simple test involves giving a small sample of blood.

Read on to find out what…. Diagnosing diabetes early means you can start treatment and take steps to a healthier lifestyle. There are a variety of tests that can diagnose….

Learn what the results mean. The triglyceride level test is a blood test that helps measure the amount of triglycerides in your blood. Triglycerides are a type of fat.

Nonfasting triglyceride levels provide an important snapshot of your health. Learn how they're used and how they differ from fasting triglyceride…. You can get an HDL test to find out the level of good cholesterol in your blood. Low-density lipoprotein LPD is a type of cholesterol. Health Conditions Discover Plan Connect. Medically reviewed by Deborah Weatherspoon, Ph. Home Common health questions Operations, tests and procedures Back to Operations, tests and procedures.

Can I eat and drink before having a blood test? Common fasting blood tests Examples of blood tests that may require you to fast include: a fasting blood glucose test used to test for diabetes — you may be asked to fast for 8 to 10 hours before the test an iron blood test used to diagnose conditions such as iron deficiency anaemia — you may be asked to fast for 12 hours before the test For more information about a wider range of blood tests, go to Lab Tests Online.