During the last five decades the metabolic syndrome has turned into an epidemic in countries with overnutrition and low levels of physical activity. About 15% of the population aged 40-75 in these countries exhibit exhibit the 'metabolic syndrome' cluster diseases. We define the metabolic syndrome as a cluster of diseases with at least three of the following components diagnosed in any one subject: ITG/type 2 diabetes, android obesity, dyslipidemia, hypertension, hyperuricemia, albuminuria and atherosclerosis. Insulin resistance was found in more than 80% of both the clinical type 2 diabetics and the subjects with IGT in the RIAD study. Intra-abdominal obesity and lipotoxicity are other important causes. Today the metabolic syndrome is--and for the near future will continue to be--the most important source of new diabetics, as well as a major cause of coronary heart disease.