Effect of high-oleic canola and flaxseed oils on energy expenditure and body composition in hypercholesterolemic subjects.
OBJECTIVE
The fatty acid profile of dietary fats may contribute to its channelling toward oxidation versus storage, influencing energy and weight balance. Our objective was to compare the effects of diets enriched with high-oleic canola oil (HOCO), alone or blended with flaxseed oil (FXCO), on energy expenditure, substrate utilization, and body composition versus a typical Western diet (WD).


METHODS
Using a randomized crossover design, 34 hypercholesterolemic subjects (n=22 females) consumed 3 controlled diets for 28 days containing ~49% energy from carbohydrate, 14% energy from protein, and 37% energy from fat, of which 70% of fat was provided by HOCO rich in oleic acid, FXCO rich in alpha-linolenic acid, or WD rich in saturated fat. Indirect calorimetry measured energy expenditure and substrate oxidation. Body composition was analyzed by dual-energy x-ray absorptiometry.


RESULTS
After 28 days, resting and postprandial energy expenditure and substrate oxidation were not different after consumption of the HOCO or FXCO diets compared with a typical Western diet. No significant changes in body composition measures were observed between diets. However, the android-to-gynoid ratio tended to increase (P=.055) after the FXCO diet compared with the HOCO diet.


CONCLUSIONS
The data suggest that substituting a typical Western dietary fatty acid profile with HOCO or FXCO does not significantly modulate energy expenditure, substrate oxidation or body composition in hypercholesterolemic males and females.
Richardson Centre for Functional Foods and Nutraceuticals, Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
Leah G
LG
Gillingham
Kimberley S
KS
Robinson
Peter J H
PJ
Jones
D015502:Absorptiometry, Photon; D001823:Body Composition; D002153:Calorimetry, Indirect; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000008:administration & dosage* / Q000032:analysis; D004734:Energy Metabolism; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage* / Q000737:chemistry; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000378:metabolism* / Q000473:pathology; D008043:Linseed Oil / Q000008:administration & dosage* / Q000737:chemistry; D008297:Male; D019301:Oleic Acid / Q000008:administration & dosage* / Q000032:analysis; D010084:Oxidation-Reduction; D000074262:Rapeseed Oil; D016037:Single-Blind Method
D004041:Dietary Fats; D005229:Fatty Acids, Monounsaturated; D000074262:Rapeseed Oil; D019301:Oleic Acid; D008043:Linseed Oil