Obesity Medicine · Clinical Pearl
Weight loss lowers energy expenditure more than body size alone predicts
Lede: After weight loss, resting and total energy expenditure can fall beyond what would be expected from the smaller body alone.
Why it matters
This phenomenon—often called adaptive thermogenesis or metabolic adaptation—reflects active neuroendocrine and physiologic energy conservation. Skeletal muscle can become more efficient, spontaneous energy expenditure may fall, and reduced leptin signaling contributes to a lower defended energy output. The magnitude varies between individuals and studies, but the clinical effect is familiar: the same calorie intake that produced early weight loss may later maintain or even permit regain.
The pearl
A weight-loss plateau does not automatically mean the patient stopped trying. The energy requirement itself may have changed.
