Cholesterol-Lowering Drugs – The Myth of the Cholesterol Myth

Some experts tell us everyone needs a cholesterol-lowering drug. Other experts tell us no one needs a cholesterol-lowering drug. Could they both be right? Here is a quick review of the myth of the cholesterol myth.

Serious students of the science of cholesterol find a lot to criticize in the last 50 years of clinical research. Before 1950, dietary fat was generally considered to be a good thing. In the late 1930’s and 1940’s most of the world’s population, even in the United States, suffered shortages of fat in the diet due to the demands of wartime.

In 1950, for instance, a reputable medical journal even published a study that found that skin rashes could be cured (and they actually were) by giving patients supplemental corn oil and lard. And about that time, cholesterol began to appear as a culprit causing heart disease.

The research studies that identified cholesterol as the cause of heart disease were really shaky. The first observation was that during World War II, in which 80,000,000 people died as a result of military action, very few people died of heart attacks. Also, very few people had access to high-fat diets. Therefore, high-fat diets must cause heart attacks.

What the researchers overlooked was the simple fact that, if something else was in fact causing heart disease, people who had weak hearts were far less likely to be able to dodge bullets and survive long enough to have an event that could be diagnosed as a heart attack.

The next decade brought the Korean conflict, and more studies of heart disease. Autopsies of American GIs killed in Korea found a shockingly high percentage had clogged arteries. This could only mean that many young people-who had for the first time in their lives had access to a high-fat diet just a few years ago-were suffering atherosclerosis, the researchers believed. But again, unfortunate soldiers who had heart disease were less able to jump into foxholes.

The reason scientists ignored the obvious flaws in the early research was that they knew that the “clogs” in arteries were made in part by cholesterol, and cholesterol was easy to measure. So rather than find what the real cause of clogged arteries might be, scientists focused on measuring cholesterol levels, which was an easy thing to do.

Then a generation of researchers did things like feeding hamburgers to Easter bunnies and noting the devastating effects of rabbit health. That research provided a great deal of what science knows about how to control cholesterol.

Some commentators conclude that cholesterol-reducing drugs are a sham, a high-level conspiracy between drug companies and public health officials to sell billions of people drugs they don’t need. And if you look at the 85% of all studies that do not find a relationship between cholesterol and heart disease, you might give the conspiracy theorists a second thought.

But it turns out that what causes clogged arteries is not the cholesterol, it’s the protein that carries one particular kind cholesterol, a kind of LDL cholesterol known as apoB100. The protein is attacked by free radicals. It attracts white blood cells that also get stuck in the lining of arteries and that calcify along with the cholesterol.

If you have high LDL cholesterol that is not attached to apoB100, you are not at any elevated risk for cardiovascular disease. If you have low LDL cholesterol but most of it is attached to this protein, then you are at increased risk for cardiovascular disease even if your total cholesterol and LDL cholesterol numbers are low.

So why not just throw out the whole system? It turns out the kinds of measurements doctors do really aren’t all that inaccurate, most of the time. Some people get treatments they don’t need, but the number is smaller than one might think:

  • Measuring the ratio of two kinds of LDL cholesterol, apoB100 and apoA1, predicts who gets cardiovascular disease correctly about 99.9% of the time.
  • Measuring the ratio of LDL to HDL cholesterol predicts who gets cardiovascular disease about 99% of the time.
  • Measuring total (apoA and apoB) LDL cholesterol predicts who gets cardiovascular disease about 97% of the time.
  • Measuring total cholesterol isn’t of any value at all. Of course, that’s the measurement we are told about.

So while the test your doctor does-assuming you don’t have unusually low triglycerides, which messes up the test-is going to give useful information about 99% of the time despite the fact that “LDL cholesterol” doesn’t cause heart disease. The things you do that lower LDL cholesterol are probably going to help, about 99% of the time. But if you want to know if you are in that other 1% and you should be doing something else, get a test for apoB100 and apoA1.

Selected Reference:

Olsson A, Holme I, Pedersen T. Apolipoprotein B/A1 ratio is a better discriminator of risk of coronary heart disease than is LDL/HDL-cholesterol ratio in the IDEAL study. Atherosclerosis. 2006:7(suppl):161. Abstract Tu-W20:4.