Normal postprandial lipemia in men with low plasma HDL concentrations.

To examine the relation between postprandial lipemia and high density lipoprotein (HDL) concentrations, we measured the plasma triglyceride and retinyl palmitate responses to 50-g fat meals of 1) 25 men with low HDL cholesterol concentrations (less than 36 mg.dl-1) and normal fasting triglyceride concentrations, 2) 25 men with normal HDL cholesterol (greater than 40 mg.dl-1) and normal fasting triglyceride concentrations, and 3) 20 men with mild to moderate fasting hypertriglyceridemia (250-347 mg.dl-1). The average magnitude of postprandial lipemia induced by the fat meals was markedly higher in the hypertriglyceridemic men (593 +/- 311 mg.dl-1.8 hr) than in either of the normolipidemic groups. In normotriglyceridemic men with low HDL cholesterol, mean postprandial lipemia (303 +/- 158 mg.dl-1.8 hr) was similar to the corresponding value of men with normal HDL (283 +/- 130 mg.dl-1.8 hr). Postprandial plasma retinyl palmitate concentrations, which reflect chylomicron remnant metabolism, also were similar in normal-HDL and low-HDL groups. These data suggest that defects in chylomicron-triglyceride clearance that give rise to excess postprandial lipemia are not a common occurrence in normolipidemic men with low HDL cholesterol concentrations. Accordingly, the low HDL cholesterol concentrations measured in the normotriglyceridemic men in this study must be attributable to factors other than an exaggerated postprandial lipemia.