Muscle loss is estimated to account for roughly 20% (1, 2, 3, 4, 5, 6) of total weight lost through typical diet‑based weight‑loss methods—including GLP‑1 drugs. Popular phrases such as “Ozempic butt,” “Ozempic face,” “Ozempic arms,” “Ozempic feet,” and “Ozempic body” suggest that GLP‑1‑induced weight loss, as well as standard calorie‑deficit dieting, causes specific muscle groups to deteriorate. However, these estimates are derived from lean body mass (LBM) measurements, which do not (7) directly measure muscle tissue.
Compounding the inaccuracy is the fact that no study has ever accurately measured participants’ total muscle tissue before weight loss. As of this writing, no standardized protocol (8) exists to quantify total muscle tissue, and no baseline average exists for comparison. Without an approved measurement standard, it is impossible to determine:
*how much muscle a person was born with (genetic baseline),
*how much they added through resistance training or intense cardio (exercise‑induced hypertrophy),
*how much they lost before dieting due to diet, exercise, and lifestyle factors (pre‑existing atrophy), or
*how much they lost due to aging (sarcopenia).
LBM remains the current proxy standard—not a direct measurement of muscle.
