Is bad cholesterol really to blame for heart attacks?

Research has shown that there are different sizes of LDL and HDL particles. Some are much more dangerous than others.

by Dr. Sima Aidun — 

You might be surprised to know that up to 50 percent of those who have suffered heart attacks had “normal” LDL (bad cholesterol) numbers. Cholesterol is carried throughout the body in little balls called lipoproteins. It is the lipoprotein, not cholesterol, that leads to clogging and blockage of the arteries. According to the National Cholesterol Education Program (NCEP) guidelines, 50 percent of people who have heart attacks have normal cholesterol.

Cholesterol testing has been used historically as the standard indicator for cardiovascular disease, with HDL known as good cholesterol and LDL known as bad cholesterol. However, it is actually the size of these particles (especially LDL), not their numbers, that are responsible for key steps in plaque formation and the resulting development of cardiovascular events such as heart attacks.

Research has shown that there are different sizes of LDL and HDL particles, and some are much more dangerous than others. LDL particles can be large or small, and the amount of cholesterol contained within these particles varies widely — but ultimately, bigger is better.

Small, dense LDLs have three times more plaque-forming capacity than larger-sized LDLs, simply because they are small enough to pass through the blood vessels and deposit cholesterol within the walls of the artery, initiating plaque formation which can lead to a stroke or heart attack.

For example, Person A who has an LDL level of 125 mg/dl packed in one large particle is less at risk for cardiovascular disease than Person B with the same level of LDL (125 mg/dl), but that is spread out in four small particles.

Standard cholesterol testing only provides part of the picture, leaving many people with normal cholesterol numbers unaware they are still at risk for a heart attack. The NCEP introduced new emerging factors that cause many individuals to be at risk of cardiovascular disease, one of them being LDL particle size, which can be identified through advanced lipoprotein testing.

Dr. Sima Aidun is a naturopathic physician in Scottsdale, Ariz., who focuses on female health issues from puberty through menopause, as well as bio-identical hormone replacement therapy. www.naturalsolutionsforwomen.net or 480-451-1602.

Reprinted from AzNetNews, Volume 27, Number 2, April/May 2008.