Triglycerides are a type of fat. Your body produces some of it, and you get some from the foods you eat. After you eat, any extra calories that your body doesn’t need immediately get turned into triglycerides. They’re kept in fat cells for storage. When your body needs energy, it releases the triglycerides into the blood. When your provider draws blood to check your overall cholesterol, he or she will also get a triglyceride count. You may need to fast for eight to 12 hours first. Your health care provider may also ask you to avoid drinking alcohol. Be sure to double check with your provider how to prepare for the test. According to the American Heart Association, there are four categories of triglyceride levels: