BACKGROUND: In Singapore, the @entity28 prevalence is disproportionately higher in the Asian-Indians and Malays than the Chinese. Lower resting energy expenditure (REE) may be a contributory factor. OBJECTIVE: We explored the association between ethnicity and REE in Chinese, Asian-Indian and Malay @entity1 living in Singapore and determined the influence of body composition, mass/volume of high metabolic rate organs, represented by brain volume and trunk @entity1386 ( @entity1386 ) and physical activity on ethnic differences. DESIGN: 244 @entity1 from Singapore (n=100 Chinese, 70 Asian-Indians and 74 Malays), aged 21 to 40 years and body mass index of 18.5 to 30.0   kg/m(2) were recruited in this cross-sectional study. REE was assessed by indirect calorimetry and body composition by dual energy X-ray absorptiometry (DXA). Brain volume was measured by magnetic resonance imaging (MRI). Physical activity was assessed by the Singapore Prospective Study Program Physical Activity Questionnaire. RESULTS: REE was significantly lower in Asian-Indians than in Chinese after adjusting for body weight. @entity1386 (total, trunk and limb) and total fat mass were important predictors of REE across all ethnic groups. Brain volume was positively associated with REE only in Malays. Moderate and vigorous physical activity was positively associated with REE only in Asian-Indians and Malays. The difference in REE between Asian-Indians and Chinese was attenuated but remained statistically significant after adjustment for total @entity1386 (59  20   kcal/day), fat mass (67  20   kcal/day) and brain volume (54  22   kcal/day). The association between REE and ethnicity was no longer statistically significant after total @entity1386 was replaced by trunk @entity1386 (which includes heart, liver, kidney and spleen) but not when it was replaced by limb @entity1386 (skeletal muscle). CONCLUSIONS: We have demonstrated a lower REE in Asian-Indians compared to Chinese that may contribute to the higher rates of @entity28 in the former. This difference could be accounted for by differences in metabolically active organs.International Journal of Obesity accepted article preview online, 16 November 2015. doi:10.1038/ijo.2015.233.

Smaller size of high metabolic rate organs explains lower resting energy expenditure in Asian-Indian Than Chinese XXXX .

@entity1 :: ('9606', 'Species') :: ['men'] @entity1386 :: ('MESH:D018205', 'Disease') :: ['fat-free mass', 'FFM'] @entity28 :: ('MESH:D009765', 'Disease') :: ['obesity']
@entity1 :: (9606,Species) :: ['men']
