Different postprandial metabolism of olive oil and soybean oil: a possible mechanism of the high-density lipoprotein conserving effect of olive oil.

The postprandial lipoprotein metabolism of two orally administered vitamin A-fat loads consisting of either 20% (wt:vol) soybean oil or 17% olive oil plus 3% soybean oil was studied in six normolipidemic young men according to a randomized crossover design. Mean (+/- SEM) retinyl palmitate concentrations (area under the 24-h curve) were higher in olive oil chylomicrons (97.3 +/- 5.5 mmol.L-1 x h-1), than in soybean-oil chylomicrons (84.0 +/- 10.5 mmol.L-1 x h-1; P < 0.02). Apolipoprotein B-48 concentrations were higher in the olive oil chylomicron remnants with densities (d) of 1.006-1.019 compared with soybean-oil remnants. The slower removal of olive oil chylomicron remnants was correlated to hepatic lipase activity (r = 0.84, P < 0.02). The initial HDL-cholesterol concentration (0.87 +/- 0.17 mmol/L--relatively low but within the normal range for young Dutch men) decreased significantly after ingestion of soybean oil to 0.66 +/- 0.10 mmol/L after 5 and 7 h, but no significant decrease was observed after olive oil ingestion. Soybean oil induced decreases in HDLs correlated inversely with hepatic lipase (r = -0.88, P < 0.02). The results suggested that competition between olive oil chylomicron remnants and HDL for hepatic lipase may have been the underlying mechanism that prevented the postprandial decrease in HDL cholesterol.

RCT Entities:   Population Interventions Outcomes