Abstract
Japan has entered an era of an aged society, and the number of patients afflicted with lifestyle-related diseases is continuously increasing. From the point of view of preventive medicine, taking into consideration the current status, the concept of metabolic syndrome has been proposed. Metabolic syndrome involves a combination of several metabolic risk factors such as abdominal obesity and insulin resistance. In this article the definition of this syndrome and its pathogenic mechanisms so far elucidated are explained.
