Available data suggest that elevated triglyceride levels in plasma, associated with increased VLDL or chylomicron remnants, are associated with premature coronary artery atherosclerosis. Whether this is a direct effect or as a result of the association of hypertriglyceridemia with decreased HDL as well as decreased LDL particle size remains to be determined. Many families with premature coronary disease have a genetic form of hypertriglyceridemia associated with decreased HDL, or with both decreased HDL and increased LDL cholesterol concentrations. In addition, subjects with severe hypertriglyceridemia in excess of 1000 mg/dl associated with elevation of plasma chylomicrons are at increased risk of developing recurrent pancreatitis. Therefore, triglycerides have been implicated in the pathogenesis of both atherosclerosis and pancreatitis.