5-HTP is a precursor for serotonin which can be further processed into melatonin. Despite this theoretical mechanism for promoting sleep, current research is limited and not particularly promising.
Some early research in the 1970s suggested that 5-HTP might increase REM sleep without affecting total sleep duration, but several participants reported experiencing nightmares.[1][2] Furthermore, a 2022 randomized controlled trial in people with Parkinson’s disease found no effect on REM sleep.[3]
In children with sleep terrors, 5-HTP was reported to significantly reduce night terror episodes, but the study was not placebo-controlled.[4]
In a 2024 study (summarized here), 5-HTP taken before bed for 12 weeks did not improve sleep but rather was reported to slightly decrease sleep duration in older adults.[5]
References
- ^Wyatt RJ, Zarcone V, Engelman K, Dement WC, Snyder F, Sjoerdsma AEffects of 5-hydroxytryptophan on the sleep of normal human subjects.Electroencephalogr Clin Neurophysiol.(1971 Jun)
- ^Zarcone V, Kales A, Scharf M, Tan TL, Simmons JQ, Dement WCRepeated oral ingestion of 5-hydroxytryptophan. The effect on behavior and sleep processes in two schizophrenic children.Arch Gen Psychiatry.(1973 Jun)
- ^Meloni M, Figorilli M, Carta M, Tamburrino L, Cannas A, Sanna F, Defazio G, Puligheddu MPreliminary finding of a randomized, double-blind, placebo-controlled, crossover study to evaluate the safety and efficacy of 5-hydroxytryptophan on REM sleep behavior disorder in Parkinson's disease.Sleep Breath.(2022 Sep)
- ^Bruni O, Ferri R, Miano S, Verrillo EL -5-Hydroxytryptophan treatment of sleep terrors in childrenEur J Pediatr.(2004 Jul)
- ^Sutanto CN, Xia X, Heng CW, Tan YS, Lee DPS, Fam J, Kim JEThe impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial.Clin Nutr.(2024-Mar)