In this study, GLP-1 increased beta cell mass by decreasing the apoptosis of the beta cells
Estrogen Exposure and Adipose-Driven Hormonal Modulation Because adipose tissue produces estrogen via aromatase, reductions in visceral fat can lower peripheral estrogen levels in some individuals
Furthermore, liraglutide, subcutaneous semaglutide, and tirzepatide are approved for chronic weight management regardless of diabetes status
doi: 10.4093/dmj.2025.0242
GIP also acts on the brain and seems to regulate fat tissue storage. Tirzepatide not only leads to more weight loss than semaglutide

During GLP-1associated weight loss, lean-mass changes are typically adaptive and preventable , not degenerative. GLP-1 Body Composition Changes: What Clinical Trials Show About Muscle Loss Clinical trials and body-composition sub-studies of semaglutide and tirzepatide consistently demonstrate: Fat mass accounts for most weight lost during treatment. Lean mass may decrease , particularly without resistance training or adequate protein intake. In many patients, the proportion of lean mass relative to total body weight is preserved or improved , because fat loss exceeds lean loss. Key clinical insight: GLP-1/GIP therapies improve overall body composition by preferentially reducing fat massnot by causing muscle breakdown. Lean mass refers to all the non-fat tissues in the bodyprimarily skeletal muscle , but also organs, bones, connective tissue, and body waterthat support metabolism, movement, and overall physical function