How is a cholesterol test performed?

In order to do a cholesterol test, a single sample of your blood will be drawn with a needle and analyzed. Some tests involve a less-invasive finger prick, but these samples are less reliable. You can have your cholesterol levels tested at your doctor's office, a hospital, a health fair, and even in some drugstores. Test results may take a couple of days, but sometimes longer, to return. Typically, you will be advised to fast for 12 hours before the blood draw. Avoid having a cholesterol screening when you're ill, losing weight, pregnant, or breastfeeding (unless your doctor requests it), since those circumstances can produce results that aren't representative of your usual cholesterol levels.

A cholesterol/lipids test is like any other blood test. Having blood drawn typically only takes a few minutes. You will be asked to roll up your shirt sleeve (if necessary) and the medical professional who will be drawing the blood will swab the area where the needle will be inserted with an alcohol wipe. A rubber tube may be tied around the upper part of your arm, or you may be asked to make a fist, to make the veins stand out more and easier to access.
 
A needle attached to a small test tube will be inserted into your vein and blood will begin to flow into the tube. When a sample that is appropriate for the test has been gathered, the needle will be removed, and you may be asked to press on a piece of gauze placed over the insertion site. This pressure will help stop any bleeding from the tiny puncture site. A bandage will then be placed over the site where the needle was inserted.
 
Your blood sample will then be sent to lab technicians for analysis. You will receive information when you have the blood test as to when you can expect results.

Some in-office machines are able to test blood obtained from a tiny fingerprick, similar to how people with diabetes check their blood sugar levels at home.