Effects of dietary cold-pressed turnip rapeseed oil and butter on serum lipids, oxidized LDL and arterial elasticity in men with metabolic syndrome

Abstract

Background. Rapeseed oil is the principal dietary source of monounsaturated and n-3 polyunsaturated fatty acids in the Northern Europe. However, the effect of rapeseed oil on the markers of subclinical atherosclerosis is not known. The purpose of this study was to compare the effects of dietary intake of cold-pressed turnip rapeseed oil (CPTRO) and butter on serum lipids, oxidized LDL and arterial elasticity in men with metabolic syndrome. Methods. Thirty-seven men with metabolic syndrome completed an open and balanced crossover study. Treatment periods lasted for 6 to 8 weeks and they were separated from each other with an eight-week washout period. Subjects maintained their normal dietary habits and physical activity without major variations. The daily fat adjunct consisted either of 37.5 grams of butter or 35 mL of VirginoR CPTRO. Participants were asked to spread butter on bread on the butter period and to drink CPTRO on the oil period. The fat adjunct was used as such without heating or frying. Results. Compared to butter, administration of CPTRO was followed by a reduction of total cholesterol by 8% (p < 0.001) and LDL cholesterol by 11% (p < 0.001). The level of oxidized LDL was 16% lower after oil period (p = 0.024). Minimal differences in arterial elasticity were not statistically significant. Conclusion. Cold-pressed turnip rapeseed oil had favourable effects on circulating LDL cholesterol and oxidized LDL, which may be important in the management of patients at high cardiovascular risk. Trial registration. ClinicalTrial.gov NCT01119690. © 2010 Palomäki et al; licensee BioMed Central Ltd.