a1 Department of Human Nutritional Sciences, Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation Drive, University of Manitoba, Winnipeg, MB, Canada R3T 6C5
a2 Section of Cardiology, Department of Internal Medicine, University of Manitoba, St Boniface General Hospital, Winnipeg, MB, Canada
Recently, novel dietary oils with modified fatty acid profiles have been manufactured to improve fatty acid intakes and reduce CVD risk. Our objective was to evaluate the efficacy of novel high-oleic rapeseed (canola) oil (HOCO), alone or blended with flaxseed oil (FXCO), on circulating lipids and inflammatory biomarkers v. a typical Western diet (WD). Using a randomised, controlled, crossover trial, thirty-six hypercholesterolaemic subjects consumed three isoenergetic diets for 28 d each containing approximately 36 % energy from fat, of which 70 % was provided by HOCO, FXCO or WD. Dietary fat content of SFA, MUFA, PUFA n-6 and n-3 was 6, 23, 5, 1 % energy for HOCO; 6, 16, 5, 7·5 % energy for FXCO; 11·5, 16, 6, 0·5 % energy for WD. After 28 d, compared with WD, LDL-cholesterol was reduced 15·1 % (P < 0·001) with FXCO and 7·4 % (P < 0·001) with HOCO. Total cholesterol (TC) was reduced 11 % (P < 0·001) with FXCO and 3·5 % (P = 0·002) with HOCO compared with WD. Endpoint TC differed between FXCO and HOCO (P < 0·05). FXCO consumption reduced HDL-cholesterol by 8·5 % (P < 0·001) and LDL:HDL ratio by 7·5 % (P = 0·008) v. WD. FXCO significantly decreased E-selectin concentration compared with WD (P = 0·02). No differences were observed in inflammatory markers after the consumption of HOCO compared with WD. In conclusion, consumption of novel HOCO alone or when blended with flaxseed oil is cardioprotective through lipid-lowering effects. The incorporation of flaxseed oil may also target inflammation by reducing plasma E-selectin.
(Received April 27 2010)
(Revised August 23 2010)
(Accepted August 24 2010)
(Online publication September 29 2010)
Abbreviations: ALA, α-linolenic acid; CRP, C-reactive protein; FXCO, flaxseed/high-oleic rapeseed (canola) oil; HOCO, high-oleic rapeseed (canola) oil; ICAM-1, intercellular adhesion molecule-1; IMT, intima-media thickness; sICAM-1, Soluble ICAM-1; sVCAM-1, soluble vascular cell adhesion molecule-1; TC, total cholesterol; WD, Western diet; VCAM-1, vascular cell adhesion molecule-1