OK, you medical types (and I mean folks who are actually up to speed on controlled studies). I have a question.

We know that high cholesterol levels, and particularly the low-density lipoproteins, are correlated with increased risk of heart disease and stroke. The theory, as I understand it, is that these are the cause of plaque which results in coronary problems.

Many people are now being prescribed drugs (usually statins) that reduce cholesterol production and measured levels. Now, I know that these have been proven to be effective in cholesterol reduction, but have they been actually shown, in clinical studies, to actually reduce risk of heart attack and stroke? In other words, because of our faith in the cholesterol-coronary link, are we treating a symptom, rather than a cause?

I understand that a study completed by Harvard in 1997 found no significant coorelation between ingestion of fats and heart disease. I wonder what's the status on that?

You are wandering into a gray area of medicine, and you could spend an awful lot of time in there without a lot of definitive answers. I know because I was deeply enmeshed in a lot of the peer-reviewed stuff on this very issue three or four years ago.

The short answer is that some cholesterol medications have been shown by clinical study to reduce overall mortality and to add at least a year or two to lifespan. Some have not. But the jury is also out on a lot of it because most of the drugs haven't been around long enough to give very concrete answers.

There are even those who question the entire notion that total cholesterol or HDL/LDL ratio are honestly related to heart disease risk. The one I'm most familiar with being a former bench researcher who later became President of the Maryland Nutrtionist's Association, Dr. Mary Enig, who I corresponded with for some time. She and a few other radicals question the entire cholesterol hypothesis from stem to stern--although they are very much in the minority, the very fact that they are not laughingstocks should tell you just how poorly medical science has a grasp on this issue.

The relationship between diet, serum lipid/lipoprotein levels, and overall health is still poorly studied. It is generally accepted by most researchers and most medical authorities that increased cholesterol, particularly HDL/LDL ratio and elevated trigylcerides, represents a significant increase in heart disease risk. The correlation is fairly well-established--causation remains another question entirely.

And will, likely for some time.

We know some of the drugs reduce overall mortality. We're pretty sure it's the changes in serum lipid/lipoprotein levels. We don't know, and the long-term studies are still being conducted.

Currently, the most prudent advice is to improve your lipids if possible. If you can do it without the drugs, great. If not, take the drugs.

It's what I'd do, FWIW.

Speaking as a 34 year old who had a mild heart attack last year and a stent installed at Christmas, all of us with heart disease would really like to know the answer to this. I've lowered my total cholesterold to 174, HDL 47, LDL 119 and that's due to 40mg lipitor, 100 mg niacin, plavix and lopressor. If the doc doesn't know if the crap works I'd like to know that's the case.

I'm seriously considering one of those 1600 calorie starvation diets....

>>I understand that a study completed by Harvard in 1997 found no significant coorelation between ingestion of fats and heart disease. I wonder what's the status on that?

It may well be true to some degree. From the literature that I have read, it is difficult to significantly lower your cholesterol by diet alone.

On the more general topic, there seems to be an evolving case that a lot of coronary artery disease may well be an effect of infection. An infection causes some damage on the artery, plaque forms as a side effect (and forms more readily if you have lots of LDL in the blood), and you get blockages. The theory is slowly gaining momentum, much like the ulcers are an infection theory did. A genetic component is probably involved also.