Life Extension Creatine Powder 300GProduct Details The body produces creatine primarily in the liver and kidneys from the amino acids arginine and glycine, with help from S adenosylmethionine. Creatine circulates through the bloodstream to help support energy for cells throughout the body, but healthy levels tend to decline as we age. 1 Lean muscle mass, exercise performance and recovery Creatine is one of the best studied nutrients for lean muscle mass, strength, and power. It is a