Impact of natural and industrial trans fatty acids consumption on HDL metabolism

Abstract

Unlike dietary industrial trans fatty acids (iTFA), which are known to increase the risk of cardiovascular disease (CVD) through adverse modifications of blood lipids, the impact of dietary trans fatty acids from ruminants (rTFA) remains unknown. The purpose of the present study was to compare the effects of iTFA and rTFA on in vivo HDL metabolism. According to a double‐blind, randomized crossover controlled study design, 9 healthy men were fed each of 3 experimental 5‐week isoenergetic diets: 1‐ high in iTFA (10.2 g/2500 kcal), 2‐ high in rTFA (10.2 g/2500 kcal) and 3‐ a control diet low in TFA (2.2 g/2500 kcal). Apolipoprotein (apo) A‐I kinetic was investigated after each diet after administration of D3‐Leucine in the fasted state. The fractional catabolic rate (FCR) and production rate (PR) of apo A‐I were significantly higher after the diet rich in iTFA than after the control diet (+12.9% and +12.6% respectively, p=0.03). No significant change in apo A‐I FCR and PR were observed after the diet rich in rTFA. When analysing all 3 diets, the apo A‐I FCR was a strong correlate of on‐diet plasma HDL‐C concentrations (r=−0.50, p=0.008). This kinetic study of apo A‐I suggested that a high consumption of rTFA may not significantly modify HDL in vivo kinetics.Supported by grants from the Dairy farmers of Canada, Novalait and the Canada Research Chair in nutrition and Cardiovascular Health.