Cholesterol is a type of fat (lipid) in your blood. Your cells need cholesterol, and your body makes all it needs. But you also get cholesterol from the food you eat.
If you have too much cholesterol, it starts to build up in your arteries. This is called hardening of the arteries. It is the starting point for some heart and blood flow problems. The buildup can narrow the arteries and make it harder for blood to flow through them. The buildup can also lead to dangerous blood clots and inflammation that can cause heart attacks and strokes. There are two types of cholesterol.