Three different references, three different answers. I guess the best answer is to ask the lab faculty before your test..... A fasting blood test is a blood sample taken from a person who has not eaten for at least 8 hours. Usually, the blood sample is taken early in the morning. Examples of blood tests that may be done after a period of fasting include fasting blood sugar (fasting plasma glucose) test and lipid profile (cholesterol and triglycerides). http://www.webmd.com/hw/health_guide_atoz/stf124124.asp Patients who are scheduled for a lipid profile test should fast (except for water) for 12-14 hours before the blood sample is drawn. If the patient s cholesterol is to be fractionated, he or she also should avoid alcohol for 24 hours before the test. http://www.healthatoz.com/healthatoz/Atoz/ency/cholesterol_test.jsp To get accurate results, you should fast for 9 to 12 hours before the test. The health care provider may advise you to stop taking drugs that can affect the test. (See Special considerations. ) You may drink water during the fast, but other beverages such as coffee, tea, or soda may affect results. http://www.pennhealth.com/ency/article/003492.htm