Tryptophan: The Molecular Key to Unlocking Superior Sleep, Mood Enhancement and Athletic Recovery
DOI:
https://doi.org/10.12775/JEHS.2025.79.58156Keywords
Tryptophan, Sleep regulation, Neurotransmitter synthesis, Irritable bowel syndrome, Gut-brain axisAbstract
Tryptophan, an essential amino acid, plays a pivotal role in regulating sleep, mental health, athletic recovery and age-specific health conditions. Sleep, a fundamental biological process critical for physical and mental well-being, is intricately linked to the availability and metabolism of tryptophan. This amino acid serves as a precursor for serotonin, a neurotransmitter involved in mood regulation and melatonin, a hormone governing the sleep-wake cycle. Tryptophan’s conversion to serotonin and subsequent synthesis of melatonin underscore its influence on circadian rhythm stabilization and sleep quality enhancement. Emerging evidence supports the therapeutic potential of tryptophan supplementation in managing insomnia, optimizing recovery in athletes, and alleviating symptoms of irritable bowel syndrome (IBS). Its role in athletic recovery is particularly significant, as improved sleep quality accelerates tissue repair and enhances overall performance. Moreover, tryptophan demonstrates age-specific benefits, addressing sleep disturbances prevalent in older adults and contributing to improved mental health outcomes across various life stages. The modulation of serotoninergic pathways by tryptophan also underscores its broader implications for mood regulation and neuropsychiatric disorders.
References
1. Pérez-Piñero, S., Muñoz-Carrillo, J. C., Echepare-Taberna, J., Muñoz-Cámara, M., Herrera-Fernández, C., Ávila-Gandía, V., Heres Fernández Ladreda, M., Menéndez Martínez, J., & López-Román, F. J. (2024). Effectiveness of enriched milk with ashwagandha extract and tryptophan for improving subjective sleep quality in adults with sleep problems: A randomized double-blind controlled trial. Clocks & Sleep, 6(3), 417–432. https://doi.org/10.3390/clockssleep6030028
2. Fernstrom, J. D. (2016). A perspective on the safety of supplemental tryptophan based on its metabolic fates. Journal of Nutrition, 146(12), 2601S–2608S. https://doi.org/10.3945/jn.115.228643
3. Sutanto, C. N., Loh, W. W., & Kim, J. E. (2022). The impact of tryptophan supplementation on sleep quality: A systematic review, meta-analysis, and meta-regression. Nutrition Reviews, 80(2), 306–316. https://doi.org/10.1093/nutrit/nuab027
4. Sutanto, C. N., Xia, X., Heng, C. W., Tan, Y. S., Lee, D. P. S., Fam, J., & Kim, J. E. (2024). The impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial. Clinical Nutrition, 43(3), 593–602. https://doi.org/10.1016/j.clnu.2024.01.010
5. Maffei, M. E. (2020). 5-Hydroxytryptophan (5-HTP): Natural occurrence, analysis, biosynthesis, biotechnology, physiology, and toxicology. International Journal of Molecular Sciences, 22(1), 181. https://doi.org/10.3390/ijms22010181
6. Kałużna-Czaplińska, J., Gątarek, P., Chirumbolo, S., Chartrand, M. S., & Bjørklund, G. (2019). How important is tryptophan in human health? Critical Reviews in Food Science and Nutrition, 59(1), 72-88. https://doi.org/10.1080/10408398.2017.1357534
7. Friedman, M. (2018). Analysis, nutrition, and health benefits of tryptophan. International Journal of Tryptophan Research, 11, 1178646918802282. https://doi.org/10.1177/1178646918802282
8. Roth, W., Zadeh, K., Vekariya, R., Ge, Y., & Mohamadzadeh, M. (2021). Tryptophan metabolism and gut-brain homeostasis. International Journal of Molecular Sciences, 22(6), 2973. https://doi.org/10.3390/ijms22062973
9. Bhat, A., Pires, A. S., Tan, V., Babu Chidambaram, S., & Guillemin, G. J. (2020). Effects of sleep deprivation on tryptophan metabolism. International Journal of Tryptophan Research, 13, 1178646920970902. https://doi.org/10.1177/1178646920970902
10. van Dalfsen, J. H., & Markus, C. R. (2019). The serotonin transporter gene-linked polymorphic region (5-HTTLPR) and the sleep-promoting effects of tryptophan: A randomized placebo-controlled crossover study. Journal of Psychopharmacology, 33(8), 948-954. https://doi.org/10.1177/0269881119855978
11. Schaafsma, A., Mallee, L., van den Belt, M., Floris, E., Kortman, G., Veldman, J., van den Ende, D., & Kardinaal, A. (2021). The effect of a whey-protein and galacto-oligosaccharides based product on parameters of sleep quality, stress, and gut microbiota in apparently healthy adults with moderate sleep disturbances: A randomized controlled cross-over study. Nutrients, 13(7), 2204. https://doi.org/10.3390/nu13072204
12. Sateia, M. J., Buysse, D. J., Krystal, A. D., Neubauer, D. N., & Heald, J. L. (2017). Clinical practice guideline for the pharmacologic treatment of chronic insomnia in adults: An American Academy of Sleep Medicine clinical practice guideline. Journal of Clinical Sleep Medicine, 13(2), 307-349. https://doi.org/10.5664/jcsm.6470
13. Paredes, S. D., Barriga, C., Reiter, R. J., & Rodríguez, A. B. (2009). Assessment of the potential role of tryptophan as the precursor of serotonin and melatonin for the aged sleep-wake cycle and immune function: Streptopelia Risoria as a model. International Journal of Tryptophan Research, 2, 23-36. https://doi.org/10.4137/ijtr.s1129
14. Wang, W., Liu, L., Tian, Z., Han, T., Sun, C., & Li, Y. (2021). Dietary tryptophan and the risk of metabolic syndrome: Total effect and mediation effect of sleep duration. Nature and Science of Sleep, 13, 2141-2151. https://doi.org/10.2147/NSS.S337171
15. Abad, V. C., & Guilleminault, C. (2018). Insomnia in elderly patients: Recommendations for pharmacological management. Drugs & Aging, 35(9), 791-817. https://doi.org/10.1007/s40266-018-0569-8
16. Ali, R., Tariq, S., Kareem, O., Fayaz, F., Aziz, T., Meenu, Pottoo, F. H., & Siddiqui, N. (2021). Nutraceuticals for sleep disorders. Combinatorial Chemistry & High Throughput Screening, 24(10), 1583-1592. https://doi.org/10.2174/1386207324666210121111446
17. Binks, H., Vincent, G. E., Gupta, C., Irwin, C., & Khalesi, S. (2020). Effects of diet on sleep: A narrative review. Nutrients, 12(4), 936. https://doi.org/10.3390/nu12040936
18. Zuraikat, F. M., Wood, R. A., Barragán, R., & St-Onge, M. P. (2021). Sleep and diet: Mounting evidence of a cyclical relationship. Annual Review of Nutrition, 41, 309-332. https://doi.org/10.1146/annurev-nutr-120420-021719
19. Segura, R., & Ventura, J. L. (1988). Effect of L-tryptophan supplementation on exercise performance. International Journal of Sports Medicine, 9(5), 301–305. https://doi.org/10.1055/s-2007-1025027
20. Halson, S. L. (2014). Sleep in elite athletes and nutritional interventions to enhance sleep. Sports Medicine, 44(Suppl 1), S13-S23. https://doi.org/10.1007/s40279-014-0147-0
21. Doherty, R., Madigan, S., Warrington, G., & Ellis, J. (2019). Sleep and nutrition interactions: Implications for athletes. Nutrients, 11(4), 822. https://doi.org/10.3390/nu11040822
22. Innocenti, A., Lentini, G., Rapacchietta, S., Cinnirella, P., Elia, M., Ferri, R., & Bruni, O. (2023). The Role of Supplements and Over-the-Counter Products to Improve Sleep in Children: A Systematic Review. International journal of molecular sciences, 24(9), 7821. https://doi.org/10.3390/ijms24097821
23. Bravaccio, C., Terrone, G., Rizzo, R., Gulisano, M., Tosi, M., Curatolo, P., & Emberti Gialloreti, L. (2020). Use of nutritional supplements based on melatonin, tryptophan and vitamin B6 (Melamil Tripto®) in children with primary chronic headache, with or without sleep disorders: a pilot study. Minerva pediatrica, 72(1), 30–36. https://doi.org/10.23736/S0026-4946.19.05533-6
24. Chojnacki, C., Gąsiorowska, A., Popławski, T., Konrad, P., Chojnacki, M., Fila, M., & Blasiak, J. (2023). Beneficial Effect of Increased Tryptophan Intake on Its Metabolism and Mental State of the Elderly. Nutrients, 15(4), 847. https://doi.org/10.3390/nu15040847
25. Sutanto, C. N., Loh, W. W., Toh, D. W. K., Lee, D. P. S., & Kim, J. E. (2022). Association Between Dietary Protein Intake and Sleep Quality in Middle-Aged and Older Adults in Singapore. Frontiers in nutrition, 9, 832341. https://doi.org/10.3389/fnut.2022.832341
26. Heitkemper, M. M., Han, C. J., Jarrett, M. E., Gu, H., Djukovic, D., Shulman, R. J., Raftery, D., Henderson, W. A., & Cain, K. C. (2016). Serum Tryptophan Metabolite Levels During Sleep in Patients With and Without Irritable Bowel Syndrome (IBS). Biological Research for Nursing, 18(2), 193–198. https://doi.org/10.1177/1099800415594251
27. Plantinga, A. M., Kamp, K. J., Wu, Q., & Chen, L. (2023). Exploration of associations among dietary tryptophan, microbiome composition and function, and symptom severity in irritable bowel syndrome. Neurogastroenterology & Motility. https://doi.org/10.1111/nmo.14545
28. Chojnacki, C., Medrek-Socha, M., & Blonska, A. (2022). A reduced tryptophan diet in patients with diarrhoea-predominant irritable bowel syndrome improves their abdominal symptoms and their quality of life. International Journal of Molecular Sciences, 23(23), 15314. https://doi.org/10.3390/ijms232315314
29. Chojnacki, J., Konrad, P., & Mędrek-Socha, M. (2024). The variability of tryptophan metabolism in patients with mixed type of irritable bowel syndrome. International Journal of Molecular Sciences, 25(5
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Copyright (c) 2025 Mateusz Drabczyk, Karolina Karoń, Anna Zygmunt, Łukasz Karoń, Emilia Pedrycz, Wojciech Grabowski, Daria Pedrycz, Grzegorz Drapała, Sławomir Karoń

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