Research

Energy balance

Bariatric surgery induces a significant decrease in Total Daily Energy Expenditure (TDEE) and metabolic adaptation at 8 weeks post-intervention, but this metabolic suppression is reversed by 52 weeks, coinciding with a sustained increase in free-living physical activity.

If you have had bariatric surgery, expect your energy expenditure to drop significantly in the first two months as your body adjusts to its new size. This 'metabolic adaptation' is normal but not necessarily permanent. The key to long-term success appears to be increasing your daily physical activity, which may help counteract this drop in energy expenditure and allow your metabolism to normalize over the course of a year.

ModerateQualifiesMEDIUM confidence
Bariatric surgery-induced weight loss decreased TDEE at 8 weeks and 1 year, resulting in metabolic adaptation after 8 weeks that was reversed at 1 year. These changes were accompanied by an increase in physical activity.
Kaja Falkenhain et al. · European Journal of Clinical Nutrition · 2024

Why this rating

The study is a prospective observational trial with a small sample size (N=17, all female) and self-selection into intervention groups, limiting causal inference despite the use of gold-standard DLW measurements.

Source

Energy expenditure, metabolic adaptation, physical activity and energy intake following weight loss: comparison between bariatric surgery and low-calorie diet

Kaja Falkenhain et al. · European Journal of Clinical Nutrition · 2024

DOI 10.1038/s41430-024-01523-8

cohort · n=17Cited 6×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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