New oral fat tolerance tests feature tailoring of the polyunsaturated/saturated fatty acid ratio to elicit a specific postprandial response.
The impact of dietary fat on postprandial metabolic biomarkers for obesity-related chronic diseases, such as type-2 diabetes and cardiovascular disease, has received significant recent attention. However, there is no standard method to evaluate the postprandial response to dietary fat alone. Our goals were to develop a novel oral fat tolerance test (OFTT) consisting solely of emulsified lipids tailored for specific fatty acid compositions and to evaluate the functionality of specific ratios of polyunsaturated/saturated fatty acid (P/S) loading on postprandial triacylglyceride (TAG) concentrations. Two OFTTs of emulsified lipids were prepared with specific P/S ratios of 0.2 and 2.0. Physical characteristics of the fat blends, including TAG composition, melting point, and emulsion droplet size were quantified. Healthy, older (age>45 y) men (n=8) underwent an 8 h postprandial study wherein they received the OFTT treatment (either the P/S ratio of 0.2 or 2.0), with a total lipid load of 1 g/kg subject body mass. All subjects received both treatments separated by at least 1 week. Both the P/S 0.2 and 2.0 OFTT significantly elevated (p<0.05) blood TAG and free fatty acid concentrations for 8 h without increasing blood glucose or serum insulin concentrations. The predominant fatty acids contained in the P/S 0.2 (palmitic acid, 16:0) and 2.0 (linoleic acid, 18:2(n-6)) OFTT blends were significantly elevated in the blood (p<0.05) during their respective postprandial periods. We concluded that blood TAGs are elevated in a specific pattern through the administration of novel OFTTs with specific P/S blends without eliciting an insulin or glucose response.
Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada.
Mark J
MJ
Dekker
Amanda J
AJ
Wright
Vera C
VC
Mazurak
Terry E
TE
Graham
Alejandro G
AG
Marangoni
Lindsay E
LE
Robinson
D000368:Aged; D001628:Beverages; D001786:Blood Glucose / Q000378:metabolism; D004041:Dietary Fats / Q000494:pharmacology*; D004311:Double-Blind Method; D004655:Emulsions; D005227:Fatty Acids / Q000097:blood / Q000737:chemistry / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000187:drug effects*; D014280:Triglycerides / Q000494:pharmacology
D001786:Blood Glucose; D004041:Dietary Fats; D004655:Emulsions; D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D005231:Fatty Acids, Unsaturated; D007328:Insulin; D008055:Lipids; D014280:Triglycerides