Lowering cholesterol prevents heart disease - right? Actually no. Although drugs like lipitor, and activities such as exercise have been shown to decrease coronary artery disease, there are other drugs (Zetia and some experimental ones) that have been very effective in lowering cholesterol, even LDL, and increasing HDL, yet have no effect on heart disease.
We need to understand the difference between an association and a cause. Heart disease is ASSOCIATED with high cholesterol, but this does not seem to be the actual cause. Drugs like lipitor, and activities like exercise not only lower cholesterol, but also decrease inflammation in the coronary arteries. This seems to be much more important. On the other hand, smoking directly causes heart disease; perhaps by increasing inflammation.
Recently there was some publicity on a drug that might decrease amyloid in the brain. Since this is associated with Alzheimers, there is hope this could be preventative. However we really don't know if the amyloid is a result of the dementia or a cause. So we need to wait and see if this drug actually prevents Alzheimers, or just amyloid. Or if it has other side effects. Studies are ongoing.
In another study, researchers found that replacing saturated fats with linoleic acid–rich vegetable oils lowers cholesterol but not deaths. " Ramsden CE et al. BMJ 2016 Apr 12. Veerman JL. BMJ 2016 Apr 12."
Although there were some minor issues with this review, it is clear that we need to be extremely careful in evaluating associations versus causes. Unfortunately the common press does not generally distinguish these issues.
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