Waist trimmers reduce inches in the midsection by increasing body temperature and by signaling the body to cool down by sweating more. However, the reduction in inches is solely from water weight lost and is only temporary.
Waist trimmer belts are generally made of nonporous synthetic rubber that does not allow ventilation. Experts warn that losing weight by dehydrating the body is unsafe and potentially results in severe medical problems. While a waist trimmer belt improves posture in some cases and gives an appearance of a slimmer body from the compression, the only scientifically supported and safe way to lose weight is through proper diet and exercise.