Effect of medium versus long chain triglyceride consumption on energy expenditure, substrate oxidation and body composition in overweight men and women

Medium chain triglycerides (MCT) have long been advocated as potential weight-lowering agents or potential tools in the treatment and prevention of human obesity. These statements have been made after findings from human and animal trials that consumption of MCT increases energy expenditure and f...

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Bibliographic Details
Main Author: St-Onge, Marie-Pierre
Other Authors: Jones, Peter J. (advisor)
Format: Others
Language:en
Published: McGill University 2003
Subjects:
Online Access:http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84436
Description
Summary:Medium chain triglycerides (MCT) have long been advocated as potential weight-lowering agents or potential tools in the treatment and prevention of human obesity. These statements have been made after findings from human and animal trials that consumption of MCT increases energy expenditure and fat oxidation compared to long chain triglycerides (LCT). In addition, animal studies have resulted in lower body weight gain and smaller fat depots when animals were fed MCT compared to those fed LCT. However, long-term controlled trials studying the effects of consumption of MCT in humans have not been conducted and the longest trial to date, 14 d of duration, has shown that the effect of MCT on energy expenditure may be transient. Therefore, we aimed to determine whether, in controlled feeding conditions, consumption of MCT for 4 wk would lead to differences in energy expenditure and substrate oxidation versus consumption of an isocaloric diet rich in LCT. Furthermore, our aim was to establish whether consumption of MCT for 4 wk would lead to greater changes in body composition than would LCT consumption. We conducted two randomized, controlled, crossover feeding trials involving overweight women and men to test our objectives. A secondary objective was to examine the potential satiating effect of MCT, and this was tested in men. Finally, a third objective was to determine whether, when combined with phytosterols and flaxseed oil, MCT consumption would result in different blood lipid profile compared to LCT. Nineteen healthy overweight women and 24 healthy overweight men participated in two separate randomized controlled trials to test these objectives. Energy expenditure and body composition were assessed at the beginning and end of each experimental phases, which differed only in the type of fat included in the controlled diets. Blood samples were also taken at baseline and endpoint of each phase to determine plasma lipid concentrations. Result