The majority of literature available that addresses the link between elevated cholesterol and heart disease focuses on making a distinction between “good” and “bad” cholesterol. This has led to the general belief that there are two main types of cholesterol: high-density (HDL) and low-density (LDL). These categories are sometimes broken down further to include very low-density cholesterol (VDL) and other fats collectively called triglycerides. However, the idea that there are different types of cholesterol is actually incorrect. In fact, there is only one kind of cholesterol and it is neither good nor bad.
Cholesterol is a fat made in the body by the liver to serve a variety of biological functions. Since this wax-like material can be found in virtually every part of the body, it can be thought of as the “glue” that binds cells together. It is also used to manufacture certain hormones and vitamin D, as well as bile acid to digest food. Since cholesterol is a fat, however, it naturally tends to separate from blood, making it necessary to hitch a ride on a stable substance to navigate through the bloodstream. To accomplish this mission, the body sends specialized proteins called lipoproteins to taxi cholesterol to where it’s needed.
However, cholesterol doesn’t simply latch onto passing proteins. In fact, quite the opposite occurs. As proteins enter the scene, they surround the cholesterol molecules to form a shield with which to keep the fat safely intact. Once bundled in this manner, the proteins then circulate in the bloodstream, carrying cholesterol along with them. The “shuttles” created to facilitate this process are known as cholesterol complexes.
This means that when referring to different types of cholesterol, what is really meant is the mode in which cholesterol is transported in the blood and its destination. For that matter, classifying cholesterol as either HDL or LDL simply identifies the type of lipoprotein transporting the substance and not the cholesterol itself since all cholesterol is the same. In fact, to be most accurate, these terms relate to the type of cholesterol complex formed when protein meets cholesterol. In this regard, there are three different types of cholesterol complexes: HDL, LDL, and VDL.
For example, high-density cholesterol has come to be known as such because it forms a complex involving high-density lipoproteins. However, low-density lipoproteins carry cholesterol in greater concentration, while very low-density lipoprotein complexes contain even more. This is how cholesterol appears as good or bad. Since LDL complexes contain more cholesterol than protein, they contribute to excess cholesterol deposits and the development of plaque in the arteries. In contrast, the formation of more HDL is considered favorable since it tends to pick up stranded LDL and carry it back to the liver for recycling or elimination.