People who set specific long-term weight loss goals do not necessarily lose more weight, and may be less likely to succeed if their goals are not realistic.
Mechanism
Synthesis from 2 studies
When you lose weight, your body naturally slows down how many calories it burns, making it harder to keep losing weight even if you stick to your diet — this is shown in 10.1002/oby.23333. If your goal is too far off, this slowdown makes it take much longer than expected, which can make you feel...
Most probable mechanism
When someone loses weight, their body slows down its energy use to conserve fuel, making it harder to keep losing weight even if they eat less — this biological slowdown means reaching a fixed, ambitious goal takes much longer than expected, which can make people feel like they're failing even when they're trying hard, as shown in the study with DOI 10.1002/oby.23333; when goals are too hard to reach, people are more likely to give up, as seen in the study with DOI 10.1556/650.2021.32128.
Weight loss reduces fat mass and fat-free mass, lowering the body's baseline energy needs as measured by changes in body composition.
The body responds to reduced energy intake and weight loss by downregulating resting metabolic rate below what is predicted by body size alone, conserving energy through hormonal and neural signals.
This metabolic adaptation reduces the daily energy deficit required for weight loss, slowing progress toward a fixed target weight even when dietary adherence is maintained.
Prolonged time to reach a specific long-term goal due to metabolic adaptation increases the likelihood of perceived failure, reducing motivation and adherence, as individuals are more likely to disengage when goals are perceived as unattainable.
Evidence from Studies
Supporting (2)
Community contributions welcome
Metabolic adaptation delays time to reach weight loss goals
Contradicting (0)
Community contributions welcome
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