As hot of a topic as this is, there are limited studies on the safety of waist trainers. One of the only medical studies can be found here (ca. 1986).
For centuries, women have used constraining undergarments to contour their bodies for a desired, shapely appearance. Recently, the search for a slimmer waist has sparked a resurgence in the use of corsets to attain an unnatural hourglass figure. While celebrities like Kim Kardashian have become proponents of waist training to reduce the size of their midsections, many share the concern that the constricting garments can be dangerous to women’s health.