Natural Factor l-Tryptophan In PakistanYou may know tryptophan as the thing that makes you sleepy after a big turkey dinner, but did you know this essential amino acid can actually be used as a workout supplement? If you’re looking to build lean muscle mass, adding L-Tryptophan to your workout regimen and healthy diet may help you achieve those gym goals!Assists in building lean muscle mass when combined with regular weight training and a balanced dietA vegetarian source of essential L-tryptophanSource of an amino acid involved in muscle protein synthesis