Most of the improvements from a tummy tuck are not related to fat removal. The repair of the abdominal muscles helps slim the waist and flatten the belly, and the excess skin removal helps reduce rolls and bulk in the midsection. Sometimes liposuction is performed, and in that case, those fat cells are gone for good. However, if you gain a significant amount of weight after your surgery, it may go to your waist and abdomen, as well as other areas.