Complete cholesterol tests, also called lipid panels, measure the levels of cholesterol and triglycerides in your blood. According to the American Heart Association, people who are 20 or older should get a lipid panel done at least every five years. More frequent testing may be required if you present a risk of heart disease or other health issues. To get an accurate reading, you must fast before your cholesterol test.
Function
Cholesterol tests, which are performed on a small blood sample, determine whether or not you are at risk of a heart attack, stroke or other health issues. According to experts at the Mayo Clinic, lipid panels usually produce four numbers: your total cholesterol, your HDL level, your LDL level and your triglycerides. Each of these readings measures a different type of fat in your blood. Doctors use the results of your comprehensive cholesterol tests to determine whether you need to alter your diet, activity level or medication regimen to achieve healthier levels.
Fasting
Fasting is essential when you're getting your cholesterol tested. Eating and drinking can affect the levels of fats in your blood, driving up your triglycerides and LDL level higher than they would be naturally. The American Heart Association recommends abstaining from food, beverages and medications for nine to 12 hours before your cholesterol test so that the doctor can get an accurate reading.
Exceptions
There are some general exceptions to the fasting rule. Drinking small amounts of water is fine during your fasting period. Additionally, most medical professionals say that it's OK to drink calorie-free, water-based beverages such as black coffee. You should not drink coffee that contains milk, cream, sugar or nondairy creamer.
Benefits
Sticking to water and black coffee before your cholesterol test gives your doctor the most accurate look at how your body functions. If your levels are normal, your doctor will likely tell you to keep up the good work. However, if any of your readings are high, even marginally so, a fasting lipid panel helps your doctor determine the best course of treatment. Though medication is an option, most doctors recommend changes to your diet and exercise routine, as well as lifestyle adjustments such as quitting smoking.
Considerations
You should check with your doctor about his specific fasting recommendations before you get your lipid panel. For example, though black coffee is generally considered to be OK, some physicians would prefer that you abstain from that as well during your fasting period. Additionally, you should not stop taking any prescription medications without getting the go-ahead from your doctor first. Though some medications, such as birth control pills, can affect your blood cholesterol, skipping them is not beneficial.
