I-L-Tryptophan iyadingeka ekukhuleni okujwayelekile kwezinsana kanye nebhalansi ye-nitrogen kubantu abadala, engakwazi ukuhlanganiswa kusuka ezintweni eziyisisekelo kubantu nakwezinye izilwane, okuphakamisa ukuthi itholakala kuphela ngokuthatha amaprotheni e-tryptophan noma aqukethe i-tryptophan emzimbeni womuntu, okugcwele ikakhulukazi ushokoledi, i-oats, ubisi, i-cottage shizi, inyama ebomvu, amaqanda, inhlanzi, izinkukhu, i-sesame, ama-alimondi, u-buckwheat, i-spirulina, namakinati, njll. i-anxiolytic, nensiza yokulala.