Weight cycling and its effects on muscle mass, sarcopenia and sarcopenic obesity.
Level 5 - mechanism / opinion, no new human data
Narrative review without systematic search or meta-analytic methodology
PubMed 40232654 · doi:10.1007/s11154-025-09963-8
What was done
This narrative review synthesized literature on the effects of weight cycling (repeated intentional weight loss followed by unintentional regain) on body composition, muscle mass, and the risk of developing sarcopenia and sarcopenic obesity.
What was found
The abstract reports no numerical data, effect sizes, or participant counts. Qualitatively, the review found that studies using precise body composition methods and those involving older subjects report disproportionately lower fat-free mass (FFM) regain relative to fat regain following weight cycling. In older and frail populations, involuntary weight cycling was noted to accelerate age-related FFM loss and associate with reduced muscle strength and elevated risk for sarcopenia and sarcopenic obesity.
Why it matters
Repeated weight loss and regain cycles may worsen long-term body composition by depleting lean mass, underscoring the need to preserve muscle during weight management in aging populations.
Limits
As a narrative review, it lacks a systematic literature search, standardized study selection, and quantitative meta-analysis. The abstract provides no quantitative effect sizes, and the findings are susceptible to confounding by age, physical activity, baseline metabolic status, and differing body composition assessment methods across cited studies.
Cited by
- supports Weight loss on GLP-1s followed by regain results in a worse body composition because lean mass is lost during weight loss while mostly fat is gained back.