Chylomicron fatty acid composition and serum lipid concentrations in subjects fed carpenin or palm oil/palm kernel oil as the major dietary fat

Abstract

This study, part of a larger study of dietary fats with different saturated fatty acid content, was performed to investigate the effect of caprenin on chylomicron fatty acid composition and postprandial serum lipid concentrations. Caprenin is a triglyceride made of caprylic acid (8:0), capric acid (10:0) and behenic acid (22:0). Thirty subjects were standardized for 3 weeks on a diet providing palm oil/palm kernel oil ( PO PKO ) as the major fat in a 38 energy % fat diet. Then, 15 subjects continued eating PO PKO while 15 switched to caprenin. After 5 weeks subjects consumed a meal with 40 g of test fat; blood was sampled at 0, 2, 4 and 6 hours. Amounts of 22:0 but not 8:0 and 10:0 varied (P<0.05 for time effect) over the 6 hour period in caprenin subjects; proportions of these fatty acids were much lower in chylomicrons than in the caprenin meal while proportions of palmitic acid (16:0) and oleic acid (18:1) were at least 4-fold higher in chylomicron lipids than in the meal. Postprandial concentrations of triglycerides in chylomicrons and serum and of cholesterol in plasma did not differ between dietary groups. These findings indicate 1) very low uptake of 8:0, 10:0 and 22:0 into chylomicrons, 2) a postprandial lipemia after caprenin comparable to that produced by other dietary fats as opposed to a fat-free meal, 3) considerable contribution of endogenously-derived fatty acids to chylomicron lipids and 4) equal effects of saturated fatty acids on pre- and postprandial concentrations of plasma cholesterol.