Understanding Cholesterol: Good vs. Bad Cholesterol Image by Cornell Blogs Cholesterol is a word you have probably heard many times, especially when discussing heart health. But what exactly is cholesterol, and why do people talk about good cholesterol and bad cholesterol ? The answer is more interesting than simply saying that one type is good and another is bad. Cholesterol is a waxy, fat-like substance that your body needs to function properly. It helps build cells and plays a role in producing certain hormones. Your body makes the cholesterol it needs, mainly in the liver, while some also comes from animal-based foods. The problem occurs when certain cholesterol-carrying particles become too high in your blood. In particular, high levels of LDL cholesterol can contribute to plaque buildup inside arteries and increase the risk of cardiovascular disease. Understanding your cholesterol numbers can help you make better decisions about diet, exercise, medical checkups, and heart h...