Influence of body composition and resting metabolic rate on variation in total energy expenditure: a meta-analysis.

The influence of body composition, resting metabolic rate (RMR), and sex on variation in total energy expenditure (TEE) was examined by using meta-analysis (13 published studies in a total of 162 adults). TEE (10.9 +/- 3.2 MJ/d) was significantly correlated with body mass (BM; weighted mean converted r = 0.68, P < 0.05) and resting metabolic rate (RMR; weighted mean converted r = 0.66, P < 0.05). The correlation coefficients, regression coefficients, and intercepts for the regression between TEE and RMR and between TEE and BM were highly variable between studies. When TEE was adjusted for RMR, there was no significant correlation with body fat, and females had a significantly lower TEE than males by 1.1 MJ/d (P = 0.005). We conclude that 1) the relationships between TEE and RMR and TEE and BM are highly variable between studies with nonzero intercepts, precluding use of the traditionally used ratios of TEE to RMR or TEE to BM for data comparison; 2) after adjustment of TEE for RMR, TEE is not associated with adiposity, and women have a significantly lower TEE than men; and, 3) there are insufficient published data to develop prediction models for TEE in adults.