
GLP-1 Weight Loss Primarily Shrinks Fat, Not Muscle, Study Finds
A new study combining mouse experiments and a small human trial finds GLP-1 obesity drugs primarily reduce fat with only modest lean-mass loss, much of which reflects non-muscle tissue such as liver fat. Muscle strength and function are largely preserved, especially with regular exercise, and DXA measurements can misclassify lean tissue. The takeaway is that fat loss drives the benefit and functional outcomes matter more than absolute muscle size.

