A waist training brace is a shaping garment that is designed to pull a persons midsection in as tight as possible, with the idea that the pulling action gives the person a sleeker, smaller waist. Waist trainers are similar to corsets and are usually made of a thick, sturdy fabric with metal boning that provides support around the torso. They wrap around the torso and fasten using a lacing system, hook-and-eye clasps, or sticky fasteners. The stiff boning runs vertically to keep the fabric of the waist trainer from bunching up where the waist gets smaller. The practice of waist training is controversial, with some people believing that it can help them achieve an hourglass figure and aid weight loss, while others warn of the potential dangers, such as harm to internal organs, reduced oxygen intake, and bruising. It is recommended to talk to a doctor before trying a waist trainer.