Clinical Systolic/diastolic blood pressure, Heart rate, Body weight (BW), B.M.I., Total body water (TBW)*, Fat-free mass (FFM) **, Fat mass (FM) *** Metabolic Fasting morning blood glucose; oral glucose tolerance test Insulin, leptin, adiponectin level Lipid profile Total, VLDL and HDL cholesterol, total triglycerides, Apolipoprotein A and B Inflammatory markers Erythrocyte Sedimentation Rate, C-reactive protein and plasma TNF alfa Patients satisfying the inclusion/exclusion criteria will have their insulin sensitivity evaluated by an euglycemic hyperinsulinemic clamp and will enter a six month treatment period with Acetylcarnitine 2 g/day. At the end of the treatment period and 2 months after treatment withdrawal, all baseline parameters, including insulin sensitivity, will then be evaluated. No changes in diet and in concomitant treatments (in particular with diuretics, ACE inhibitors, angiotensin II receptor antagonists, dihydro and non-dihydro calcium channel blockers, statins) will be introduced throughout the whole study period.