Statins might just prove to be real miracle drugs. They do a great job at lowering cholesterol, and they also appear to have a multitude of other medical benefits. They work by altering the metabolism of cholesterol, a complex fat that the body needs for many purposes. For example, cholesterol forms a vital component of cell membranes and nerve sheaths; it forms the basis of sex hormones; and it enables bile acids to process the food we eat. Most of the body’s cholesterol is produced by liver cells, and most of the rest comes from the food we eat.
Cholesterol is insoluble in water, so it can’t circulate in blood plasma without a protective shroud of lipoproteins, which are part fat and part protein. Cholesterol’s ultimate destination depends on whether the shroud consists of low-density lipoprotein (LDL) or high-density lipoprotein (HDL). LDL particles deliver cholesterol to cells throughout the body; HDL particles mop up excess cholesterol and carry it back to the liver for disposal. If the body produces more LDL cholesterol than the cells can absorb, it settles in artery walls and contributes to atherosclerotic plaque. That’s why LDL is often called “bad” cholesterol and HDL “good” cholesterol — even though the body needs both kinds.