Research

Energy balance

The body defends against energy imbalance by adaptively adjusting energy expenditure (specifically Basal Metabolic Rate and physical activity efficiency), meaning weight loss from caloric restriction or exercise is slower and less than predicted by simple linear energy density calculations.

Do not expect weight loss to be linear. When you cut calories or increase exercise, your body will lower its metabolic rate and activity efficiency to conserve energy. This means you will lose less weight than a simple '3500 calories = 1 lb fat' calculation predicts. Patience and consistency are required because your body actively resists the change.

GoodQualifiesHIGH confidence
The body defends itself against an imbalance between EI and EE by adjusting, within limits, the one to the other... A negative energy balance results in a reduction of basal metabolic rate (BMR) through a loss of BM and a reduction of EE per unit BM.
Klaas R. Westerterp et al. · British Journal Of Nutrition · 1995

Why this rating

The model is validated against three controlled human studies (energy restriction, overfeeding, exercise) with discrepancies within measurement precision.

Source

Energy intake, physical activity and body weight: a simulation model

Klaas R. Westerterp et al. · British Journal Of Nutrition · 1995

DOI 10.1079/bjn19950037

mechanism_onlyCited 199×
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DOI resolved against Crossref · corpus check 2026-06-10

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