Most of the cholesterols in your blood are actually produced by your liver. Ultimately, they are used to make certain sorts of hormones and also the myelin sheath of your nerve cells which seems to act as a natural insulation.
When we look at your total cholesterol, we are mainly interested in two kinds: the LDL (low-density lipoproteins) or "bad cholesterol", and the HDL (high-density lipoprotein) or "good cholesterol". Also, we are measuring another kind of cholesterol-like class of chemicals called triglycerides (TG for short). The optimal levels of these depend strongly on each individual, and can be affected by diet and exercise and medications.
We have known for decades that people who have high LDL levels have more heart attacks and strokes, and that (if necessary) using 'statin cholesterol-lowering drugs reduces the number of heart attacks and strokes that actually occur. As long as the 'statin is not harming you, we feel pretty good about you not having a heart attack or a stroke!
We have also known that people with high TG levels and/or low HDL levels also have more heart attacks and stokes. Therefore, we reasoned that (if necessary) using medications to lower TG levels and/or raise HDL levels would also reduce the occurrence of heart attacks and strokes. Prescription medicines of this sort include NiaSpan, Lopid, TriCor and WelChol. Over-the-counter ones include niacin and Omega-3 fish oils.
Well, not so much.
It turns out that using medicines to lower TG levels or raise HDL levels improves your lab test results, but not your actual likelihood of having a heart attack or a stroke. This is one of those examples of science in action. Seems like a good idea based on scientific understanding;
try it out, but if further study fails to show that it doesn't actually help, then stop doing it. Thus, many medical journals are encouraging doctors to stop using these medicines in their patients.
Mind you, 'statin drugs are still clearly shown to reduce heart attack and stroke risks as well as lowering LDL levels. The 'statins seem not only to reduce the LDL levels, but also reduce inflammation in the microscopic inner lining of blood vessels (the endothelium). This latter property helps to keep cholesterol plaques from suddenly rupturing and forming a blood clot in blood vessels going to your heart or brain. This would explain why the 'statins are beneficial and other types of medication are not.
Prescription and over-the-counter medicines for your cholesterol are not a substitute for making good choices about your diet, and exercising regularly.
The 'statin drugs have been found to lower your risk of heart attack or stroke.
Other drugs have been found to improve your lab test results, but not your health.
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