Now Foods L-tryptophan Powder, 2-Ounce
L-Tryptophan is an essential amino acid important in human nutrition for the synthesis of melatonin and serotonin, hormones regulating mood and stress response.  L-Tryptophan helps support relaxation, sleep, positive mood and immune function.*  As an essential amino acid, it is not synthesized by the body and must be obtained fromt he diet.  NOW® L-Tryptophan is pharmaceutically pure - every lot is tested to be free of Peak E and microbial contamination.