Because most of your fat is stored in the tissue directly beneath the skin, when the fat is gone, the skin will sometimes sag.
The skin will shrink, but not as rapidly as the fat is lost. Six to 12 months after surgery you will see the worst of the sagging skin. Younger patients may have skin that is more elastic, so their skin may not sag as much as older patients.
Some patients may wish to have excessive skin surgically removed by a plastic surgeon. However, we recommend waiting 18 to 24 months after surgery, when weight loss has stabilized.