Primary and secondary prevention clinical trials have demonstrated that statins markedly reduced cardiovascular risks even in patients whose plasma level of low-density lipoprotein cholesterol is lower than that of drug-treatment goal in lipid management guidelines. The reasons are as follows: The "normal" level in guidelines is not the normal level biologically, it is merely an average value in a given human group; The composition of plasma lipids is very complex; Statins have effects other than lipid modifying. Statins should be prescribed in patients without hyperlipidemia but with risk factors or coronary heart disease.