Shapewear by what you want smoothed or solved. Every page gives a verdict first, then the fit rule, then the size. Some say no; those are the pages that make the rest believable.
Shapewear that doesn't roll down when you sitA bodysuit is the cut that does not roll, because the straps hold the waist from above. The adjustment is the straps: set them for your torso length, and if they pull at their longest, the size is one band too small.