The metabolic syndrome is a topic of hot debate among experts due to different opinions about its definition and its clinical relevance. The metabolic syndrome is identified by the presence of abnormalities of the glucose metabolism, blood pressure, fat deposition, and some plasma lipids. Several authors have attempted to find a physiopathological explanation for the association of the abnormalities in this syndrome. Recently, some aspects of the inflammation seem relevant to understand the association of visceral fat deposition, insulin-resistance and diabetes and vascular complications. From a clinical point of view this syndrome must be considered an important vascular risk factor.