A body lift may involve liposuction of the abdomen, flanks and back in addition to skin excision
The result will be a tighter and aesthetic silhouette. It is right to assume that fat will be excised from the areas, and this will mean that there will be a more limited ability to accumulate fat in this area.
This does not mean, however, that a poor lifestyle will not lead to fat accumulation in the area. Indeed the remaining fat cells can get larger and will cause fat to reaccumulate at  an albeit slower rate
What s more likely to happen, is that the rest of your boy, i.e arm, thighs, neck, and upper back will put on weight at a normal rate, and the waist at a slower rate. This will lead to unusual fat distribution and make you  look strange