What Is Cholesterol and What Are the Types?

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Summary & Participants

Cholesterol is necessary to keep the body functioning but too much of the "bad" cholesterol called LDL can cause more damage than good. Tune in to learn about the different types.

Medically Reviewed On: July 21, 2012

Webcast Transcript

ANNOUNCER: When most people hear the word cholesterol they automatically think about "high cholesterol levels" and all the fatty foods associated with it.

Too much cholesterol in the bloodstream can cause damage to the blood vessels and heart and eating animal-derived foods such as meat, eggs and dairy products can increase your chances of developing high cholesterol. But not all cholesterol is bad for the body and not all cholesterol comes from your diet. As a matter of fact, the body naturally produces cholesterol and it needs "good" cholesterol to function so it's important to know the difference between the good and the bad types.

NANETTE K. WENGER, MD, FACC: Cholesterol is one of the blood fats, and we have heard so much about cholesterol lately, and likely one of the better divisions is the good cholesterol and the bad cholesterol.

SPENCER B. KING, MD, MACC: Cholesterol has many types. The two big components are called LDL (low-density lipoprotein) and HDL (high-density lipoprotein). And simplistically, we talk about the LDL being the bad cholesterol and the HDL being the good cholesterol.

That means that the bad cholesterol tends to accumulate in the arteries, tends to form plaques, tends to be the precursor to what eventually might end up being a heart attack.

The good cholesterol actually acts in part in reversing the cholesterol transport, takes cholesterol out of the plaque in the artery and may return it to the circulation, to the liver, to be excreted. So these are the two major categories, but within each one there are different particles, different cholesterols, different lipoproteins that carry the cholesterol, and they are differentially difficult players.

Some of the LDL cholesterol that is the bad cholesterol is worse than others. And it tends to be the small particle size that are very dense. You can think of the cholesterol particles as marbles, maybe, the small dense ones, and the larger, lighter ones might be ping-pong balls. And so the small marble ones are more dangerous.

On the other side, the HDL, the good cholesterol, there are some components of that that are better than others. So cholesterol is quite a complicated subject, and we're developing more and more therapies that aim not just at the total cholesterol, but in altering the good and the bad.