low density lipoprotein. Lipoproteins (particles composed of lipids and protein) are the form in which fats are transported throughout the body, in the bloodstream. LDL transport cholesterol from the liver to the tissues of the body. A high proportion of cholesterol carried in LDL (LDL-cholesterol) is associated with an increased likelihood of developing cardiovascular diseases (heart disease and stroke). Oxidized LDL appear to play an important role in the development of atherosclerosis.