title: Fractional oxidation of chylomicron-derived oleate is greater than that of palmitate in healthy adults fed frequent small meals.
abstract: Differences in oxidation of individual dietary fatty acids could contribute to the effect of dietary fat composition on risk factors for non-insulin-dependent diabetes mellitus and cardiovascular disease. Using a novel stable isotope technique, we compared fractional oxidation of chylomicron-derived oleate and palmitate in 10 healthy adults in a crossover study. 1-(13)C-labeled oleate or palmitate was emulsified into a eucaloric formula diet administered each 20 min for 7 h to produce a plateau in excretion of (13)C label in breath CO(2). Unlabeled oleate and palmitate each provided 16% of dietary energy, and other fatty acids provided 8% of energy. Total dietary fat was 40% of energy, carbohydrate was 46%, and protein was 14%. Diet without tracer was fed for 2 h before beginning tracer administration to establish a baseline fed state. Relative oxidation of oleate versus palmitate was defined as fractional oxidation of oleate divided by fractional oxidation of palmitate. Relative oxidation averaged 1.21 (99.5% confidence interval = 1.03;-1.39), indicating that fractional oxidation of oleate was significantly greater than that of palmitate.
authors.affiliation: Children's Research Institute, The Ohio State University, Room W209, Children's Hospital, 700 Children's Drive, Columbus, OH 43205-2696, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Schmidt
authors.forename: J B
authors.initials: JB
authors.lastname: Allred
authors.forename: C L
authors.initials: CL
authors.lastname: Kien
mesh_terms: D000328:Adult; D002153:Calorimetry, Indirect; D002245:Carbon Dioxide / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D002914:Chylomicrons / Q000737:chemistry*; D004032:Diet; D005230:Fatty Acids, Nonesterified / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008297:Male; D019301:Oleic Acid / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D010084:Oxidation-Reduction; D010168:Palmitates / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D002914:Chylomicrons; D005230:Fatty Acids, Nonesterified; D010168:Palmitates; D002245:Carbon Dioxide; D019301:Oleic Acid