Creatine is one of the most popular supplements available today! It is also one of the most researched, studied and talked about supplements. Creatine is found naturally in your body and is formed of three amino acids, L-methionine, glycine and L-arginine. It is also in red meat and seafood. The main job of creatine is to supply energy to your cells, specifically, muscle cells. It can help improve your workouts, increase your energy and ultimately increase your body mass.