title: Energy requirements of urban Chinese adults with manual or sedentary occupations, determined using the doubly labeled water method.
abstract: OBJECTIVE
  To examine total energy expenditure (TEE) in relation to occupation and reported leisure time activities in free-living Chinese adults, and to determine whether measured TEE values differ from current international dietary energy recommendations.
  
  
  METHODS
  Seventy three weight-maintaining adults aged 35-49 y, leading unrestricted lives in urban Beijing, with a wide variety of occupations.
  
  
  METHODS
  A cross-sectional study in which TEE was determined by doubly labeled water, body composition by deuterium oxide ((2)H(2)O) dilution, resting energy expenditure (pREE) by prediction equations, and occupational and leisure time activities by questionnaire.
  
  
  RESULTS
  For men and women respectively, TEE averaged 12.10+/-0.32 and 9.53+/-0.23 MJ/day (P<0.001), and physical activity level (PAL=TEE/pREE) was 1.77+/-0.04 and 1.66+/-0.02 (P<0.05). Fat-free mass (FFM) was the single best predictor of TEE (adjusted r(2)=0.71, P<0.001). Occupational category (light, moderate and heavy) further predicted TEE, independent of FFM (adjusted multiple r(2)=0.82, P<0.001). Both TEE adjusted for weight and PAL increased with occupational category. Measured TEE was slightly but significantly higher than the 1985 FAO/WHO/UNU estimates for women with light occupations, but did not differ from estimates for men with light occupations, or for adults with moderate or heavy occupations.
  
  
  CONCLUSIONS
  Level of occupational activity, but not duration or type of leisure activity, significantly predicted TEE in free-living urban Chinese adults. Current energy requirement recommendations slightly underestimated the energy needs of women with light occupations but were accurate for men and women with moderate and heavy occupations.
  
  
  BACKGROUND
  NIH grants DK53404 and F32-DK09747.
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts 02111, USA.
authors.forename: M
authors.initials: M
authors.lastname: Yao
authors.forename: M A
authors.initials: MA
authors.lastname: McCrory
authors.forename: G
authors.initials: G
authors.lastname: Ma
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: G G
authors.initials: GG
authors.lastname: Dolnikowski
authors.forename: S B
authors.initials: SB
authors.lastname: Roberts
mesh_terms: D000328:Adult; D001823:Body Composition / Q000502:physiology*; D001834:Body Water / Q000378:metabolism; D002681:China; D003430:Cross-Sectional Studies; D003903:Deuterium; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D007201:Indicator Dilution Techniques; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009751:Nutritional Requirements; D009790:Occupations / Q000145:classification*; D011795:Surveys and Questionnaires; D014505:Urban Population; D014867:Water
chemical_list: D014867:Water; D003903:Deuterium