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...
Fasting times ranged from 1 hour to more than 16 hours. Lipid results included the mean levels of HDL cholesterol, low-density lipoprotein (LDL) cholesterol, total cholesterol, and triglycerides. A total of 209,180 participants were included in the analysis. Authors used linear regression models to project average cholesterol levels at various fasting times.