Cholesterol ... is the Jekyll and Hyde of the body.

Like the literary split personality, it has a good side

because it is needed for certain important body functions.

But for many Americans, cholesterol also has an evil side.

When present in excessive amounts, it can injure blood

vessels and cause heart attacks and stroke.



The body needs cholesterol for digesting dietary fats,

making hormones, building cell walls, and other important

processes. 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 called

atherosclerosis.



When blood flow to the heart is impeded, the heart muscle

becomes starved for oxygen, causing chest pain (angina).

If a blood clot completely obstructs a coronary artery

affected by atherosclerosis, a heart attack (myocardial

infarction) or death can occur



Heart disease is the number one killer of both men and women

in this country. More than 90 million American adults, or

about 50 percent, have elevated blood cholesterol levels,

one of the key risk factors for heart disease, according to

the National Heart, Lung, and Blood Institute's National

Cholesterol Education Program.



While the institute estimates that heart disease killed

nearly half a million in 1996, the most recent year for

which figures are available, a study published in the New

England Journal of Medicine in September 1998 says heart

disease deaths have declined steadily over the last 30

years.



Indeed, between 1990 and 1994, heart disease deaths

decreased by 10.3 percent, the study says. From this and

other studies, it appears that this is due largely to

improvements in medical care after heart attack, a reduction

in the number of repeat heart attacks, and better prevention

of heart disease development.



A key factor in this drop is that the public, patients and

doctors today are better informed about the risks associated

with elevated cholesterol and the benefits of lifestyle

changes and medical measures aimed at lowering blood

cholesterol.



"Public health initiatives such as the National

Cholesterol Education Program have raised consumer

awareness, promoted effective interventions, and have likely

contributed to the reduction in heart disease deaths," says

David Orloff, M.D., of the Food and Drug Administration's

division of metabolic and endocrine drug products.



Another factor in the drop may be a relatively new class of

drugs called statins. These have provided doctors with an

arsenal of therapies to lower elevated blood cholesterol

levels, often dramatically. To date, FDA has approved six

statin or cholesterol lowering drugs. Which we'll cover in

more detail in upcoming articles.