Amino acids are essential to the human body. Athletes and bodybuilders can especially benefit from supplementing amino acids because they aid in repair, growth, and development of muscle tissue. The body, through assimilation of amino acids, produces over 50,000 proteins and over 15,000 enzymes. Amino acids are not only responsible for the production of all the body's enzymes (including digestive enzymes), but they also play a key role in normalizing moods, concentration, aggression, attention, sleep, and sex drive. After protein is consumed, it is broken down into amino acids. Then, individual amino acids are used to create necessary body proteins and enzymes. Digestive enzymes break down the proteins a person consumes into amino acids.