Among women who are overweight and have not gone through menopause, those whose resting metabolic rate drops more than expected after losing 16% of their body weight tend to take longer to reach a...
Mechanism
Synthesis from 1 study
After losing weight, the body burns fewer calories at rest than expected, even when the person eats the same low-calorie diet — this slowdown is a real biological response that makes further weight loss harder and slower, as shown in women who lost 16% of their weight on a strict diet...
Most probable mechanism
After losing weight, the body burns fewer calories at rest than expected based on its new size, making it harder to keep losing weight even when eating the same low-calorie diet — this slowdown is caused by changes in hormones and energy use that help the body conserve energy, and it directly makes weight loss take longer, as shown in people who lost 16% of their weight on a strict diet (10.1002/oby.23333).
Weight loss reduces fat mass and fat-free mass, lowering the baseline energy demands of metabolically active tissues.
Reduced energy intake and body mass trigger hormonal and neural signals — including decreased leptin, altered thyroid hormone activity, and reduced sympathetic nervous system tone — that downregulate resting metabolic rate independently of changes in body composition.
This adaptive reduction in resting metabolic rate creates a smaller-than-expected daily energy deficit, slowing the rate of further weight loss despite consistent dietary adherence.
The prolonged time to reach a BMI of 25 kg/m² reflects the cumulative effect of this energy conservation mechanism, where each 10 kcal/day reduction in metabolic rate adds approximately one day to the time needed to achieve the goal.
Evidence from Studies
Supporting (1)
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Metabolic adaptation delays time to reach weight loss goals
Contradicting (0)
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