title: Affordable measurement of human total energy expenditure and body composition using one-tenth dose doubly labelled water.
abstract: BACKGROUND
  The doubly labelled water (DLW) method is the technique of choice for measurement of free-living total energy expenditure (TEE) in humans. A major constraint on the clinical applicability of the method has been the expense of the (18)O isotope.
  
  
  METHODS
  We have used a reduced-dose (one-tenth of the currently recommended standard dose) of DLW for the measurement of TEE and body composition in nine healthy adult male volunteers.
  
  
  RESULTS
  TEE measured by reduced-dose DLW was positively correlated with resting energy expenditure measured by metabolic cart (r=0.87, P<0.01). Isotope-derived fat mass and body mass index were strongly correlated (r=0.86, P<0.01). In four subjects in whom we performed a complementary evaluation using standard-dose isotope enrichment, the TEE measurements were satisfactorily comparable (mean+/-s.d.: reduced dose 2586+/-155 kcal/day vs standard dose 2843+/-321 kcal/day; mean difference 257+/-265 kcal/day).
  
  
  CONCLUSIONS
  These data indicate that DLW measurements of human energy expenditure and body composition can be performed at a substantially reduced dose (and cost) of isotope enrichment than is currently employed.
authors.affiliation: Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong. d_v_mann@hotmail.com
authors.forename: D V
authors.initials: DV
authors.lastname: Mann
authors.forename: C S
authors.initials: CS
authors.lastname: Ho
authors.forename: L
authors.initials: L
authors.lastname: Critchley
authors.forename: B S P
authors.initials: BS
authors.lastname: Fok
authors.forename: E W H
authors.initials: EW
authors.lastname: Pang
authors.forename: C W K
authors.initials: CW
authors.lastname: Lam
authors.forename: N M
authors.initials: NM
authors.lastname: Hjelm
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D001823:Body Composition; D015992:Body Mass Index; D002153:Calorimetry, Indirect; D017666:Deuterium Oxide / Q000378:metabolism*; D006801:Humans; D008297:Male
chemical_list: D017666:Deuterium Oxide