Objective: To study the effect of partially hydrogenated fish oil (PHFO-diet), partially hydrogenated soybean oil (PHSO-diet) and butterfat (butter-diet) on the susceptibility of low density lipoprotein (LDL) to in vitro oxidative modification.
Design: A strictly controlled, randomized, single-blind dietary study with cross-over design.
Subjects: Thirty-three healthy men aged from 21 to 46 years entered the study; 29 men completed the study.
Interventions: Fat provided approximately 35% of the energy intake in all three test diets, and the content of trans-fatty acids was 8.0, 8.5 and 0.9% of energy in the PHFO-, PHSO- and butter-diets, respectively. The subjects consumed all three test diets each during three weeks, in a single-blind, random order. LDL isolated from the participants given the three different diets was subjected to Cu(2+)-induced oxidation.
Results: No significant differences were seen on either conjugated dienes, lipid peroxides, uptake by macrophages or relative electrophoretic mobility of LDL. Vitamin E level in serum from subjects on the PHFO-diet was significantly higher compared to the two other diets. Furthermore, no significant differences were found in the composition of the LDL particle between the three diet groups.
Conclusions: Our results indicate that consumption of trans-fatty acids does not alter the susceptibility of LDL to oxidative modification.