How you prepare

By Mayo Clinic Staff

Generally you're required to fast, consuming no food or liquids other than water, for nine to 12 hours before the test. There is some evidence that fasting doesn't make much difference in cholesterol levels, but for now, most doctors will tell you to fast. You can drink water in the time leading up to the test, but avoid coffee, tea and other beverages.

Talk to your doctor about any other special requirements. Some medications, such as birth control pills, can increase your cholesterol levels. For this reason, if you take these or other medications, your doctor might want you to stop taking them for a few days before your test. However, in some cases, if you take a medication regularly, your doctor may want you to continue it to see the effect it has on your cholesterol levels.

Nov. 12, 2014