When body fat drops quickly, the face loses subcutaneous volume. Cheeks flatten. The under-eye area looks thinner. Folds that fat had softened reappear. This happens with any rapid weight loss: bariatric surgery, calorie restriction, illness, or medication-assisted loss.

The American Academy of Dermatology frames the issue as a body-change effect, not a skin-aging effect of the peptide. The skin itself has not aged; the volume underneath it has decreased.

Two factors the dermatology literature names consistently: the speed of the weight loss (slower preserves more volume) and the age at which the loss happens (younger skin recovers more elasticity).