title: Immediate metabolic availability of dietary fat in combination with carbohydrate.
abstract: We tested the hypothesis that when fat is ingested in combination with carbohydrate, direct release of fatty acids into the plasma may occur. Eight normal subjects ingested two meals: high-fat (80 g fat, 80 g carbohydrate, and 18 g protein) and low-fat (< 1 g fat, otherwise closely matched). Over the subsequent 6 h, net fat oxidation was greater after the high-fat meal (20.7 vs 10.6 g, P < 0.01). Plasma nonesterified fatty acid (NEFA) concentrations were markedly suppressed after the low-fat meal, but relatively maintained after the high-fat meal (P < 0.01). The profile of plasma NEFAs changed after the high-fat meal, consistent with entry of meal-derived fatty acids into the NEFA pool. We suggest that after ingestion of combinations of carbohydrate and fat, the action of lipoprotein lipase on chylomicron-triacylglycerol leads to direct release of fatty acids into the plasma and increased fat oxidation.
authors.affiliation: Oxford Lipid Metabolism Group, Nuffield Department of Clinical Medicine, University of Oxford, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Griffiths
authors.forename: S M
authors.initials: SM
authors.lastname: Humphreys
authors.forename: M L
authors.initials: ML
authors.lastname: Clark
authors.forename: B A
authors.initials: BA
authors.lastname: Fielding
authors.forename: K N
authors.initials: KN
authors.lastname: Frayn
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D002153:Calorimetry, Indirect; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004041:Dietary Fats / Q000097:blood / Q000378:metabolism*; D004734:Energy Metabolism; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D010101:Oxygen Consumption; D014280:Triglycerides / Q000097:blood / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D014280:Triglycerides