title: Metabolic responses to dietary fatty acids in obese women.
abstract: BACKGROUND
  The composition of fatty acids in a diet may differentially affect metabolism, thus playing a role in the development of obesity. Our purpose was to study the effects of three high-fat (HF) meals with different dietary fatty acid compositions on the thermic effect of meal (TEM) and substrate oxidation in obese premenopausal women.
  
  
  METHODS
  16 healthy obese women, aged 18-39 years, participated in a single-blinded randomized cross-over study, in which they consumed isocaloric HF meals (70% of energy from fat) rich in either saturated fat (SFA), monounsaturated fat (MUFA) or polyunsaturated fat (PUFA). Indirect calorimetry was used to measure respiratory gases for a 5-hour postprandial period. Data collected was used to determine respiratory exchange ratio (RER) for assessing substrate oxidation, and energy expenditure for the determination of TEM.
  
  
  RESULTS
  There was a significant time effect on both substrate oxidation and TEM (p<0.05). With and without using RMR as a covariate, there were no significant differences in TEM between test meals (TEM of 10.8±0.8 vs 11.0±1.0 kcal ∗ 5 h for high-MUFA vs. high-SFA meals, respectively, p=0.06). No treatment difference was found for postprandial substrate utilization (4.9±0.4, 4.9±0.3 and 4.6±0.4 g of fat oxidation following SFA, MUFA, and PUFA-rich HF meals, respectively; 13.2±0.9, 13.3±0.5 and 13.9±0.6 g of carbohydrate oxidation following SFA, MUFA, and PUFA-rich HF meals, respectively).
  
  
  CONCLUSIONS
  In premenopausal obese women, HF meals rich in either MUFAs, PUFAs, or SFAs did not differentially affect TEM or postprandial substrate oxidation.
authors.affiliation: Department of Nutritional Sciences, Texas Tech University, PO Box 41240, Lubbock, TX 79409, USA.
authors.forename: Hui C
authors.initials: HC
authors.lastname: Clevenger
authors.affiliation: Department of Nutritional Sciences, Texas Tech University, PO Box 41240, Lubbock, TX 79409, USA.
authors.forename: Jada L
authors.initials: JL
authors.lastname: Stevenson
authors.affiliation: Department of Nutritional Sciences, Texas Tech University, PO Box 41240, Lubbock, TX 79409, USA. Electronic address: jamie.a.cooper@ttu.edu.
authors.forename: Jamie A
authors.initials: JA
authors.lastname: Cooper
mesh_terms: D000293:Adolescent; D000328:Adult; D001823:Body Composition; D002153:Calorimetry, Indirect; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000494:pharmacology; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D006801:Humans; D009765:Obesity / Q000378:metabolism*; D019518:Postprandial Period / Q000187:drug effects*; D016037:Single-Blind Method; D022722:Thermogenesis / Q000187:drug effects; D055815:Young Adult
chemical_list: D004041:Dietary Fats; D005227:Fatty Acids
keywords: Acute feeding; Diet induced thermogenesis; Dietary fatty acids; RER; Substrate oxidation