Effects of adiposity and body composition on adjusted resting energy expenditure in women.
Level 4 - case-series / case-control
Cross-sectional observational study comparing resting energy expenditure across adiposity tertiles
PubMed 33961322 · doi:10.1002/ajhb.23610
What was done
Women were categorized into tertiles based on body fat percentage (%fat) measured by dual-energy X-ray absorptiometry (DXA): Tertile 1 (18.5%–28.4%), Tertile 2 (28.5%–33.8%), and Tertile 3 (34.0%–61.0%). The authors assessed measured and adjusted resting energy expenditure (REE), body composition (skeletal lean mass, fat mass), and the proportional contribution of skeletal lean mass and fat mass to adjusted REE.
What was found
Main effect across tertiles was statistically significant (p = .001). REE was higher in Tertile 3 compared to Tertile 1 by 281 kcal/day (p = .001) and Tertile 2 by 215 kcal/day (p = .001). The relative metabolic contribution of skeletal lean mass to adjusted REE was 3.2% higher in Tertile 1 compared to Tertile 3 (p = .001). Conversely, the fat mass contribution to adjusted REE was higher in Tertile 3 compared to Tertile 1 by 5.1% (p = .001) and Tertile 2 by 3.9% (p = .001).
Why it matters
This study highlights that fat mass contributes more substantially to adjusted resting energy expenditure in women with elevated body fat, suggesting fat mass explains meaningful variance in metabolic rate across adiposity levels.
Limits
The total sample size, age range, and recruitment details are not reported in the abstract. The cross-sectional design precludes causal conclusions, and the findings are restricted exclusively to female participants without accounting for potential unmeasured metabolic or hormonal confounders.
Cited by
- supports Lean body mass accounts for approximately 70% to 80% of the variance in basal metabolic rate and total energy expenditure.