title: Brown adipose tissue is involved in diet-induced thermogenesis and whole-body fat utilization in healthy humans.
abstract: Brown adipose tissue (BAT) is a potential therapeutic target against obesity and diabetes through thermogenesis and substrate disposal with cold exposure. The role of BAT in energy metabolism under thermoneutral conditions, however, remains controversial. We assessed the contribution of BAT to energy expenditure (EE), particularly diet-induced thermogenesis (DIT), and substrate utilization in human adults.
  
  
  
  In this cross-sectional study, BAT activity was evaluated in 21 men using18F-fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography (18F-FDG-PET/CT) after cold exposure (19 °C). The subjects were divided into BAT-positive (n=13) and BAT-negative (n=8) groups according to the18F-FDG-PET/CT findings. Twenty-four hour EE, DIT and respiratory quotient were measured using a whole-room indirect calorimeter at 27 °C.
  
  
  
  Body composition, blood metabolites and 24-h EE did not differ between groups. DIT (%), calculated as DIT divided by total energy intake, however, was significantly higher in the BAT-positive group (BAT-positive: 9.7±2.5%, BAT-negative: 6.5±4.0%, P=0.03). The 24-h respiratory quotient was significantly lower (P=0.03) in the BAT-positive group (0.861±0.027) than in the BAT-negative group (0.889±0.024).
  
  
  
  DIT and fat utilization were higher in BAT-positive subjects compared to BAT-negative subjects, suggesting that BAT has a physiologic role in energy metabolism.
authors.affiliation: Health Care Food Research Laboratories, Kao Corporation, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hibi
authors.affiliation: Health Care Food Research Laboratories, Kao Corporation, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Oishi
authors.affiliation: Department of Nutrition, Tenshi College, Sapporo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Matsushita
authors.affiliation: Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yoneshiro
authors.affiliation: Health Care Food Research Laboratories, Kao Corporation, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Nutritional Science, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Usui
authors.affiliation: Health Care Food Research Laboratories, Kao Corporation, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yasunaga
authors.affiliation: Health Care Food Research Laboratories, Kao Corporation, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Katsuragi
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, National Center for Global Health and Medicine, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kubota
authors.affiliation: Department of Nutritional Science, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Tanaka
authors.affiliation: Department of Nutrition, Tenshi College, Sapporo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Saito
mesh_terms: D002001:Adipose Tissue, Brown / Q000000981:diagnostic imaging / Q000378:metabolism*; D000328:Adult; D044466:Asian People; D003080:Cold Temperature; D003430:Cross-Sectional Studies; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D019788:Fluorodeoxyglucose F18 / Q000627:therapeutic use; D064368:Healthy Volunteers; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D022722:Thermogenesis / Q000502:physiology*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18