Slim Jeans (product)  Slim Jeans was the name of a weight-reducing product heavily marketed in the United States through television commercials in the 1980s. Slim Jeans were a pair of pants, very unlike jeans and more like sweatpants, made of a silver reflective material. They were supposed to help the wearer lose weight by trapping body heat and promoting the loss of "water weight" through sweating. Slim Jeans also came with a hooded sweatshirt made of the same material. The product and commercial, which became the subject of discussion on X-Entertainment, are considered by some to be unintentionally comic. Monty Python even parodied the product in their skit "Trim Jeans Theater".