For the study, researchers compared cholesterol testing results of 300,000 people from Denmark, Canada, and the U.S. In both the U.S. and Canada, fasting for eight hours before a test is required. In Denmark, however, it is not.
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/Ato...
A lipid panel typically measures several substances associated with cholesterol, including LDL, HDL, triglycerides and total cholesterol. Food does not immediately affect LDL and HDL. Total cholesterol and triglycerides are sensitive to food intake. You will need to fast for 9 to 12 hours before having your blood drawn for a lipid profile. This means you cannot have anything, except water, to eat or drink before your blood test.