Longevity & AgingGLP-1 Weight Loss Drugs in Older Adults Raise Muscle Loss Questions
GLP-1 receptor agonists such as liraglutide, semaglutide, and tirzepatide produce substantial weight loss, but roughly 25% of that loss can be lean mass, which worries clinicians treating older adults at risk of sarcopenia. This scoping review pulls together trial and mechanistic data. Fat mass falls more than lean mass, and imaging studies suggest less fat infiltration in muscle, which points to better muscle quality. However, direct data on muscle strength and physical function in older adults are sparse and inconsistent, and one 24-month retrospective study linked semaglutide to declines in muscle mass and walking speed. The authors recommend pairing these drugs with resistance exercise, a calorie-controlled diet, and 1.2–1.6 g/kg/day of protein, with dietitian support to manage gastrointestinal side effects.
