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Updated: Oct 24, 2025

Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice
Published on: November 11, 2021
Daily energy expenditure through the human life course
Herman Pontzer1,2, Yosuke Yamada3,4, Hiroyuki Sagayama5
1Department of Evolutionary Anthropology, Duke University, Durham, NC, USA. herman.pontzer@duke.edu j.speakman@abdn.ac.uk yyamada831@gmail.com sagayama.hiroyuki.ka@u.tsukuba.ac.jp aluke@luc.edu jennifer.rood@pbrc.edu dschoell@nutrisci.wisc.edu k.westerterp@maastrichtuniversity.nl wwong@bcm.edu.
None:
Total daily energy expenditure ("total expenditure") reflects daily energy needs and is a critical variable in human health and physiology, but its trajectory over the life course is poorly studied. We analyzed a large, diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 years. Total expenditure increased with fat-free mass in a power-law manner, with four distinct life stages. Fat-free mass-adjusted expenditure accelerates rapidly in neonates to ~50% above adult values at ~1 year; declines slowly to adult levels by ~20 years; remains stable in adulthood (20 to 60 years), even during pregnancy; then declines in older adults. These changes shed light on human development and aging and should help shape nutrition and health strategies across the life span.
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