Statin treatment prevents cardiovascular diseases probably beyond their lipid-lowering effect. Increasing evidence suggests that statins might increase the risk of new-onset diabetes; however, diabetes is known to increase the risk of cardiovascular diseases. The majority of the literature suggests an increased risk of new-onset diabetes in patients treated with statins in a number of different settings and that the risk appears greatest among the more potent statins. Furthermore, a dose-response curve has been shown between statin treatment and the development of diabetes. Possible mechanisms include muscle insulin resistance, lower expression of GLUT-4 in adipocytes impairing glucose tolerance and suppression of glucose-induced elevation of intracellular Ca(2+) level. However, other side effects have been reported such as increased risk of myotoxicity, increased liver enzymes, cataracts, mood disorders, dementias, hemorrhagic stroke and peripheral neuropathy, which should maybe be added to the increased risk of new-onset diabetes, when considering the risk- benefit ratio of statin treatment.