Cholesterol Cholesterol is a type of fat known as lipid which, in moderate amounts, is useful to the body. One important function of cholesterol, which is obtained from our liver and the food we eat, is to help the body make new cells. However, we must constantly keep our cholesterol levels in check. This is because excess cholesterol will build up in our arteries, making it difficult for blood to flow to our tissues and to our heart. this can lead to serious problems, including heart attacks and strokes.