Research

Energy balance

Obese women exhibit significantly higher total free-living energy expenditure than lean women, contradicting the hypothesis that obesity is caused by reduced energy expenditure.

If you are obese, your body likely burns more calories than a lean person of similar height due to the energy cost of moving and maintaining larger mass (both fat and fat-free mass). The idea that you have a 'slow metabolism' causing obesity is scientifically unsupported by this study. The issue is likely that you are consuming more energy than you realize, not that you are burning less.

GoodRefutesHIGH confidence
Average energy expenditure was significantly higher in the obese group (10-22 versus 7-99 MJ/day (2445 versus 1911 kcal/day); p<0-001) resulting from an increase in the energy cost of both basal metabolism and physical activity.
Ann Prentice et al. · BMJ · 1986

Why this rating

Uses the doubly labelled water method (gold standard for free-living TEE) and whole body calorimetry, though sample size is small (n=22).

Source

High levels of energy expenditure in obese women.

Ann Prentice et al. · BMJ · 1986

DOI 10.1136/bmj.292.6526.983

cohort · n=22Cited 583×
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DOI resolved against Crossref · corpus check 2026-06-10

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