This is the VOA Special English Health Report.

Sometimes people have the idea that all cholesterol in the bloodis bad. But the body needs this fatty substance to create cells andhormones. The liver produces all the cholesterol we need.

Low-density lipoprotein, or L.D.L., carries cholesterol into theblood. L.D.L. that is not used by cells is called "bad" cholesterol.High-density lipoprotein, H.D.L., is considered "good." H.D.L.gathers up the unused cholesterol and moves it back to the liver.The liver then destroys it.

If L.D.L. levels are too high, then the blood has morecholesterol than the H.D.L. can remove. The extra cholesterol sticksto the inside of the arteries. This can restrict blood flow or causeblockages that result in heart attacks and strokes. For this reason,doctors often place more importance on high levels of H.D.L., thegood cholesterol.

But new research questions this way of thinking. Daniel Rader isa professor who does cholesterol research at the University ofPennsylvania School of Medicine. Doctor Rader agrees that highH.D.L. is a good thing. In general, he says, people with higherlevels of good cholesterol have less chance of a heart attack.

Yet many doctors see patients with high levels of both good andbad cholesterol. These patients may not receive drugs to lower theirbad cholesterol because their H.D.L. level is high. Such drugs arecalled statins. But Doctor Rader says high H.D.L. alone does notprovide enough protection.

Currently doctors are told to treat patients with heart diseaseor diabetes until their L.D.L. is below a level of one-hundred. ButDoctor Radar notes new findings that even this may not be low enoughto protect against heart attack or stroke.

Doctors know that lowering bad cholesterol reduces the risk ofheart attacks. But the new study shows that lowering it moreaggressively lowers that risk even more.

The findings are from a study called PROVE-IT. The study wasreleased at a meeting of the American College of Cardiology. Areport will appear in the New England Journal of Medicine.

The risk of heart disease increases in people who smoke tobacco,weigh too much or do not exercise. Other influences are high bloodpressure, age and family history.

This Special English Health Report was written by Jerilyn Watson.