Dissociation between postprandial lipemia and high density lipoprotein cholesterol concentrations in...

Previous studies have indicated an inverse relation between circulating high density lipoprotein (HDL) concentrations and the rate of chylomicron clearance. Because chronic exercise has been shown to augment chylomicron clearance, we measured HDL cholesterol concentrations and plasma triglyceride and retinyl palmitate responses to high- (140 g) and low- (50 g) fat meals in endurance-trained men. Plasma HDL cholesterol concentrations in these men ranged from 36 to 105 mg/dl. Intraindividual variation in the cholesterol concentration of the HDLs occurred primarily in HDL2. The magnitude of postprandial lipemia induced by both the high- and the low-fat meals was uniformly low compared with values reported previously for sedentary men and was not correlated with HDL cholesterol concentrations. Postprandial retinyl palmitate concentrations, which reflect chylomicron remnant metabolism, also showed no correlation with HDL cholesterol concentrations. These data indicate that the degree of postprandial lipemia is not the primary determinant of HDL cholesterol concentrations in endurance-trained men. Accordingly, the wide range of HDL cholesterol concentrations measured in these men must be attributable to other factors.