title: Short-term supplementation with a specific combination of dietary polyphenols increases energy expenditure and alters substrate metabolism in overweight subjects.
abstract: OBJECTIVE
  Impaired regulation of lipid oxidation (metabolic inflexibility) is associated with obesity and type 2 diabetes mellitus. Recent evidence has indicated that dietary polyphenols may modulate mitochondrial function, substrate metabolism and energy expenditure in humans. The present study investigated the effects of short-term supplementation of two combinations of polyphenols on energy expenditure (EE) and substrate metabolism in overweight subjects.
  
  
  METHODS
  Eighteen healthy overweight volunteers (9 women, 9 men; age 35±2.5 years; body mass index 28.9±0.4 kg m(-2)) participated in a randomized, double-blind cross-over trial. Combinations of epigallocatechin-gallate (E, 282 mg day(-1))+resveratrol (R, 200 mg day(-1)) and E+R+80 mg day(-1) soy isoflavones (S) or placebo capsules (PLA) were supplemented twice daily for a period of 3 days. On day 3, circulating metabolite concentrations, EE and substrate oxidation (using indirect calorimetry) were measured during fasting and postprandial conditions for 6 h (high-fat-mixed meal (2.6 MJ, 61.2 E% fat)).
  
  
  RESULTS
  Short-term supplementation of E+R increased resting EE (E+R vs PLA: 5.45±0.24 vs 5.23±0.25 kJ min(-1), P=0.039), whereas both E+R (699±18 kJ 120 min(-1) vs 676±20 kJ 120 min(-1), P=0.028) and E+R+S (704±18 kJ 120 min(-1) vs 676±20 kJ 120 min(-1), P=0.014) increased 2-4 h-postprandial EE compared with PLA. Metabolic flexibility, calculated as the postprandial increase to the highest respiratory quotient achieved, tended to be improved by E+R compared with PLA and E+R+S only in men (E+R vs PLA: 0.11±0.02 vs 0.06±0.02, P=0.059; E+R+S: 0.03±0.02, P=0.009). E+R+S significantly increased fasting plasma free fatty acid (P=0.064) and glycerol (P=0.021) concentrations compared with PLA.
  
  
  CONCLUSIONS
  We demonstrated for the first time that combined E+R supplementation for 3 days significantly increased fasting and postprandial EE, which was accompanied by improved metabolic flexibility in men but not in women. Addition of soy isoflavones partially reversed these effects possibly due to their higher lipolytic potential. The present findings may imply that long-term supplementation of these dosages of epigallocatechin-gallate combined with resveratrol may improve metabolic health and body weight regulation.
authors: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: J
authors: J
authors: Most
authors: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: G H
authors: GH
authors: Goossens
authors: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: J W E
authors: JW
authors: Jocken
authors: Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: E E
authors: EE
authors: Blaak
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000627:therapeutic use*; D015992:Body Mass Index; D002392:Catechin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D019587:Dietary Supplements; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000178:diet therapy* / Q000378:metabolism; D010084:Oxidation-Reduction; D059808:Polyphenols / Q000627:therapeutic use*; D019518:Postprandial Period; D000077185:Resveratrol; D013267:Stilbenes / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D059808:Polyphenols; D013267:Stilbenes; D002392:Catechin; C045651:epigallocatechin gallate; D000077185:Resveratrol