‘I’ve lost my butt’: how rapid weight loss can leave you with less muscle and more fat Rapid weight loss, potentially from GLP-1 drugs like Mounjaro, is raising concerns about consequences beyond the number on the scale. Experts are debating the risks of losing lean mass and potential issues in older age associated with this trend. The discussion highlights how decades of modern dieting culture have impacted our bodies.

• GLP-1 drugs like Mounjaro are causing rapid weight loss in millions.
• Concerns exist regarding the risks of rapid weight loss, including loss of lean mass.
• Potential consequences in older age are part of the debate.
• The discussion extends to the broader impact of modern dieting culture on body composition.