A recent study presented at the European Congress on Obesity shows that patients treated with GLP-1 or dual GLP-1/GIP receptor agonists (semaglutide or tirzepatide) experienced significant fat loss with minimal lean muscle mass loss over six months. Conducted by researchers from Hofstra/Northwell and New York Weight Wellness Medicine, the prospective study followed 200 adults with overweight or obesity. Participants received medication along with guidance on resistance training and protein intake. Body composition was measured at baseline, three months, and six months using bioelectrical impedance analysis.

Results showed average weight loss of 12% in women and 13% in men, primarily due to fat loss. Muscle loss was minimal—about 0.6 kg in women and 1 kg in men. High medication adherence and consistent protein intake were linked to better muscle retention. Researchers concluded that, with expert supervision, muscle loss during weight reduction using GLP-1-based therapies can be minimized. Further investigation is underway to compare outcomes between semaglutide and tirzepatide, and to explore the long-term role of diet and exercise in muscle preservation.

Reference: Kohli K. Lean muscle mass loss minimized during weight loss therapy using newer incretin obesity drugs, suggests study. Medical Dialogues. Published April 11, 2025. Accessed July 7, 2025. https://medicaldialogues.in/medicine/news/lean-muscle-mass-loss-minimized-during-weight-loss-therapy-using-newer-incretin-obesity-drugs-suggests-study-146397