Cholesterol, like fat, cannot move around the bloodstream on its own because it does not mix with water. The bloodstream carries cholesterol in particles called lipoproteins that are like blood-borne cargo trucks delivering cholesterol to various body tissues to be used, stored or excreted. But too much of this circulating cholesterol can injure arteries, especially the coronary ones that supply the heart. This leads to accumulation of cholesterol-laden “plaque” in vessel linings, a condition.