subject: Does Cholesterol Cause Atherosclerosis? [print this page] A few years ago it would be considered criminal ignorance to even think that cholesterol and arteriosclerosis are not related. Fortunately for all of us, things have changed a lot. Although it still feels a bit uncomfortable to accept it, indeed research is proving that these two little fellows do not go hand by hand. In fact it has been shown that people with low and high cholesterol had equally developed atheromatic plaques in their heart arteries. The funny thing is that experiments on this started as early as in 1936 and continued by many important researchers. It is very strange that they have been ignored for so long. Such projects were also done in many countries: Poland, Guatemala, USA, Canada. So there are plenty of experimental data
A few studies found a correlation though. One of the most influential of those studies used data from the Framingham study. The correlation factor is a statistical measure scientists use when they try to measure how well or bad two factors are correlated. This factor ranges from 0 to 1, with 1 being 100% correlation and 0 no correlation at all. From a statistical point of view, a bare minimum of 0.5 is a bare minimum to prove possible correlation. The experimentalists of this study calculated a correlation coefficient of 0.36 between the level of blood cholesterol and arteriosclerosis. Statistically speaking, this is totally unacceptable or at least would be so if this study was dealing with any other subject. How can such a poorly designed and biased study like this ever managed to create even the slightest controversy. Besides the statistics, many points in the analysis showing biased and unreliable ways of collecting and handling data became obvious during peer reviews. This goes not only for the above study but for the Framingham study as well. The scientists responsible for them were absolutely determined to prove a positive correlation between cholesterol and arteriosclerosis no matter what.
After 40 years, the director of the famous Framingham study had to admit: "In Framingham, Mass, the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower the persons serum cholesterol. . . we found that the people who ate the most cholesterol, ate the most saturated fat, ate the most calories, weighed the least and were the most physically active." The study showed that those who weighed more and had abnormally high blood cholesterol levels were slightly more at risk for future heart disease; but weight gain and cholesterol levels had an inverse correlation with fat and cholesterol intake in the diet.
Finally scientists have studied the differences between Japan and the States. Japan is a country with very low rates of heart attacks and low blood cholesterol levels in the general population. The arteries of the Americans and the Japanese people were found to be in similar condition.
One could use at this point the fact that people on statins (cholesterol lowering drugs) have lower risks for heart disease. The only problem with these experiments is that the protective role of statins was equal to people with high and low blood cholesterol. Specifically in the studies testing the statins the cardioprotective effect of these drugs was present equally to patients with low or high cholesterol levels. This leads us the suspicion that this effect might be due to a different reason and not cholesterol levels as it has been falsely promoted so much. Indeed if we examine the mechanism statins use, we find out that they inhibit the synthesis of a very important molecule called mevalonate, which is used by the liver to synthesize cholesterol. The details of the biochemical pathways are of no importance at this point but the only extra piece of information we need is that mevalonate is a precursor molecule for many more things, not just cholesterol. Further experiments reveal that statins affect the ability of platelets to stick to each other by preventing them to produce a substance that triggers just that. This means that the mechanism of blood clogging is blocked thus leading to substantially lower number of infractions i.e. heart attacks and strokes. Also statins were found to lower the activity of smooth muscle cells. One of the first steps in the advancement of atherosclerosis is the migration of smooth muscle cells at the points of arterial damage. By inhibiting these two actions, statins are able to provide some protection from heart attacks. Please note that both mechanisms are cholesterol independent confirming the experimental data that statins have such an effect equally to people with low or high blood cholesterol.
Statins are not to be taken lightly though. They have severe side effects that do not compensate even for the small cardioprotective role they have. It is a pretty long list but a list of the most common ones would have to include severe muscle damage, kidney and liver failure, memory loss and impaired cognitive functions. Increased risk for cancer has been strongly associated with statins. Also women taking statins during the first trimester of their pregnancy, gave birth to babies with severe malformations. in some cases even worse than the thalidomide victims.
It is of massive importance to educate ourselves on what the facts are on the cholesterol topic. We have been so misled that it is essential to go back to the source of information to find out the truth. The cholesterol topic has been abused in so many ways, therefore we need to take a holistic look at this matter and not just take into account the studies that are most convenient. This is the only way to establish an efficient ans safe medical practice in the near future.
