5-HTP

Written By Brittyn Coleman, MS, RDN/LD

What is 5-HTP?

  • 5-HTP (5-Hydroxytryptophan) is made in your body via an amino acid called tryptophan. Tryptophan is not made by the body, so you must get it from your diet.

  • 5-HTP is a chemical that is made in the body from the essential amino acid, tryptophan, and is vital for the creation of both serotonin and melatonin. Children on the autism spectrum have shown to have abnormal levels of serotonin and imbalanced 5-HTP conversion. Appropriate levels are important for sleep, mood, and behavior, implicating further research.

  • 5-HTP is important for serotonin production, which is supportive in producing melatonin. Appropriate serotonin and melatonin levels are important for mood, sleep, hunger, immune function, and other important physiological functions. 

  • Abnormal serotonin levels have been implicated in poor sleep, depression, anxiety, aggression, appetite, temperature regulation, sexual behaviour, and pain sensation. [1]

  • Many studies find evidence of dysregulation of serotonin in autism and suspect this may play an important role in ASD psychopathology. [2]

  • Gut health is also an important factor for conversion of tryptophan into serotonin. Healthy balance of the gut microbiome can support this process. [3]

  • Therapeutic administration of 5-HTP has been shown to be effective in treating a wide variety of conditions, including depression, fibromyalgia, binge eating associated with obesity, chronic headaches, and insomnia. [1]

 
 

Food Sources of 5-HTP

While dietary sources don’t contain direct 5-HTP, foods containing the amino acid tryptophan will help create 5-HTP in the body. Foods containing tryptophan include:

 
 

Is 5-HTP Beneficial for Autism?

  • In a Randomized Control Trial of 18 male autistic patients (ages 13-19) and 22 matched non-autistic controls, 5-HTP or a placebo was given. At baseline, there were no significant differences in 5-HTP levels between groups.

  • However, once researchers administered 5-HTP, serotonin levels significantly increased in the autistic group and not in the controls. 

  • Differences in the metabolism of serotonin were made clear after loading with 5-HTP, but not during baseline. This suggests that serotonin metabolism is different in autistic individuals, and may be a significant finding to promote future research and understanding of the pathophysiology in autism. [5-7]

  • Elevated brain-derived neurotrophic factor (BDNF) levels and lower tryptophan and kynurenic acid (KA) levels were characteristics of both childhood autism and intellectual disability disorder, while elevated tryptophan and lower serotonin (5-HT) synthesis were hallmarks of Asperger syndrome. [8]

  • Through the Boston Birth Cohort, 996 cord blood samples were collected at birth and measured for select metabolites including 5-methoxytryptophol (5-MTX), 5-hydroxytryptophan (5-HTP), serotonin, and N-acetyltrytophan and later diagnosis of ASD, ADHD, and developmental disabilities (DD). They found that higher cord levels of 5-MTX were associated with lower risk of ASD and ADHD, higher cord levels of tryptophan, 5-HTP, and N-acetyltryptophan were associated with higher risk of ADHD. Cord serotonin was not associated with ASD, ADHD, and other DD. [9]

  • Adequate levels of both serotoinin and vitamin D are suspected to reduce the prevalence of autism. Researchers suggested supplementation with vitamin D and tryptophan is a practical and affordable solution to help prevent autism and possibly ameliorate some symptoms of the disorder. [10]

  • In a mouse model, BALB/c mice (often used as a model of human psychiatric disorders characterized by elevated anxiety and altered sociability) showed more sociability when treated with carbidopa/5-HTP. [11]

Night Terrors

  • After 1 month of treatment with 5-HTP supplementation, 29/31 (93.5%) of patients (ages 3-10 years) showed a positive response (reduction in night terrors). In the comparison group without drug therapy, after 1 month, the episodes disappeared only in four children (28.6%) while ten children (71.4%) showed the persistence of episodes with the same frequency as before. After 6 months, 26/31 (83.9%) of children treated with L -5HTP were sleep terror-free, while in five children (16.1%) sleep terror episodes persisted. Of the children in the comparison group, ten (71.4%) continued to show sleep terrors at 6-month follow-up. [12]

  • Supplements including melatonin, iron, vitamin D, and 5-hydroxytryptophan (5-HTP)  may be helpful in children with sleep disturbances and neurodevelopmental disabilities, but more research is needed for dosing regimens and tolerability. [13]

Gut Health

  • In a mouse model, reduced release of serotonin contributes to defects in the enteric nervous system and gastrointestinal motility, which indicates a link between mood dysfunction and constipation. Administration of slow release 5-HTP to these mice restored serotonin to the enteric nervous system and normalized gastrointestinal motility. [14]

Supplementation

There is conflicting information whether children should supplement with 5-HTP. There are very few studies that have been conducted regarding its safety in children, but the studies that have been completed in children have shown promising results (see studies in the Research section below).

We suggest consulting with your child’s healthcare provider before starting 5-HTP supplements to ensure it’s a good fit for your child. 5-HTP supplements should not be taken with antidepressants and all medications should be evaluated for interactions before beginning 5-HTP.

If you do supplement with 5-HTP, we recommend high quality 5-HTP supplements like Pure Encapsulations and Designs for Health.

DISCLAIMER: Before starting any supplement or medication, always consult with your healthcare provider to ensure it is a good fit for your child. Dosage can vary based on age, weight, gender, and current diet.

Author

Brittyn Coleman, MS, RDN/LD, CLT

  • [1] Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Altern Med Rev. 1998 Aug;3(4):271-80. PMID: 9727088.

    [2] Yang CJ, Tan HP, Du YJ. The developmental disruptions of serotonin signaling may involved in autism during early brain development. Neuroscience. 2014 May 16;267:1-10. doi: 10.1016/j.neuroscience.2014.02.021. Epub 2014 Feb 27. PMID: 24583042.

    [3] Agus A, Planchais J, Sokol H. Gut Microbiota Regulation of Tryptophan Metabolism in Health and Disease. Cell Host Microbe. 2018 Jun 13;23(6):716-724. doi: 10.1016/j.chom.2018.05.003. PMID: 29902437.

    [4] Carpenter, S. (2012, September). That gut feeling. Monitor on Psychology, 43(8). https://www.apa.org/monitor/2012/09/gut-feeling

    [5] Croonenberghs J, Spaas K, Wauters A, Verkerk R, Scharpe S, Deboutte D, Maes M. Faulty serotonin--DHEA interactions in autism: results of the 5-hydroxytryptophan challenge test. Neuro Endocrinol Lett. 2008 Jun;29(3):385-90. PMID: 18580847.

    [6] Croonenberghs J, Wauters A, Deboutte D, Verkerk R, Scharpe S, Maes M. Central serotonergic hypofunction in autism: results of the 5-hydroxy-tryptophan challenge test. Neuro Endocrinol Lett. 2007 Aug;28(4):449-55. PMID: 17693983.

    [7] Croonenberghs J, Verkerk R, Scharpe S, Deboutte D, Maes M. Serotonergic disturbances in autistic disorder: L-5-hydroxytryptophan administration to autistic youngsters increases the blood concentrations of serotonin in patients but not in controls. Life Sci. 2005 Mar 25;76(19):2171-83. doi: 10.1016/j.lfs.2004.06.032. PMID: 15733932.

    [8] Ormstad H, Bryn V, Verkerk R, Skjeldal OH, Halvorsen B, Saugstad OD, Isaksen J, Maes M. Serum Tryptophan, Tryptophan Catabolites and Brain-derived Neurotrophic Factor in Subgroups of Youngsters with Autism Spectrum Disorders. CNS Neurol Disord Drug Targets. 2018;17(8):626-639. doi: 10.2174/1871527317666180720163221. PMID: 30033880.

    [9] Raghavan R, Anand NS, Wang G, Hong X, Pearson C, Zuckerman B, Xie H, Wang X. Association between cord blood metabolites in tryptophan pathway and childhood risk of autism spectrum disorder and attention-deficit hyperactivity disorder. Transl Psychiatry. 2022 Jul 9;12(1):270. doi: 10.1038/s41398-022-01992-0. PMID: 35810183; PMCID: PMC9271093.

    [10] Patrick RP, Ames BN. Vitamin D hormone regulates serotonin synthesis. Part 1: relevance for autism. FASEB J. 2014 Jun;28(6):2398-413. doi: 10.1096/fj.13-246546. Epub 2014 Feb 20. PMID: 24558199.

    [11] Russo AM, Payet JM, Kent S, Lesku JA, Lowry CA, Hale MW. Acute treatment with 5-hydroxytryptophan increases social approach behaviour but does not activate serotonergic neurons in the dorsal raphe nucleus in juvenile male BALB/c mice: A model of human disorders with deficits of sociability. J Psychopharmacol. 2022 Jul;36(7):806-818. doi: 10.1177/02698811221089039. Epub 2022 Apr 27. PMID: 35475390.

    [12] Bruni O, Ferri R, Miano S, Verrillo E. L -5-Hydroxytryptophan treatment of sleep terrors in children. Eur J Pediatr. 2004 Jul;163(7):402-7. doi: 10.1007/s00431-004-1444-7. Epub 2004 May 14. PMID: 15146330.

    [13] Bruni O, Angriman M, Melegari MG, Ferri R. Pharmacotherapeutic management of sleep disorders in children with neurodevelopmental disorders. Expert Opin Pharmacother. 2019 Dec;20(18):2257-2271. doi: 10.1080/14656566.2019.1674283. Epub 2019 Oct 22. PMID: 31638842.

    [14] Israelyan N, Del Colle A, Li Z, Park Y, Xing A, Jacobsen JPR, Luna RA, Jensen DD, Madra M, Saurman V, Rahim R, Latorre R, Law K, Carson W, Bunnett NW, Caron MG, Margolis KG. Effects of Serotonin and Slow-Release 5-Hydroxytryptophan on Gastrointestinal Motility in a Mouse Model of Depression. Gastroenterology. 2019 Aug;157(2):507-521.e4. doi: 10.1053/j.gastro.2019.04.022. Epub 2019 May 7. PMID: 31071306; PMCID: PMC6650329.

Brittyn Coleman, MS, RDN/LD https://www.autismdietitian.com
Previous

Sulforaphane