Liothyronine Sodium T3 is a synthetic hormone that has been used to increase the activity of the thyroid gland. It is used on the side as a supplement, with more popularity resting on its T-3 promotion alongside anabolic steroid use. Bodybuilders have been using it to increase the metabolism in their cells. With the use of T3 Cytomel, the parts of the cells referred to as mitochondria will burn more nutrients and cause the cells to perform more efficiently. Fat will be burned from the body with T3 Cytomel thanks to the effect that it has.