The impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial

Clarinda Nataria Sutanto; Xuejuan Xia; Chin Wee Heng; Yue Shuian Tan; Delia Pei Shan Lee; Johnson Fam; Jung Eun Kim

doi:10.1016/j.clnu.2024.01.010

The impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial

Clin Nutr. 2024 Mar;43(3):593-602. doi: 10.1016/j.clnu.2024.01.010. Epub 2024 Jan 17.

Authors

Clarinda Nataria Sutanto¹, Xuejuan Xia², Chin Wee Heng³, Yue Shuian Tan⁴, Delia Pei Shan Lee⁵, Johnson Fam⁶, Jung Eun Kim⁷

Affiliations

¹ Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: cnsfst@nus.edu.sg.
² Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: xiaxj@usst.edu.cn.
³ Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: chin.wee@nus.edu.sg.
⁴ Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: tanyueshuian@u.nus.edu.
⁵ Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: lee.delia@u.nus.edu.
⁶ Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, NUHS Tower Block, 1E Kent Ridge Road Level 11, Singapore 119228, Singapore; Department of Psychiatry, Singapore General Hospital, Singhealth Academia Level 3, 20 College Road, Singapore 169856, Singapore. Electronic address: pcmjf@nus.edu.sg.
⁷ Department of Food Science and Technology, Faculty of Science, National University of Singapore, Science Drive 2, Singapore 117542, Singapore. Electronic address: fstkje@nus.edu.sg.

PMID: 38309227
DOI: 10.1016/j.clnu.2024.01.010

Abstract

Background & aims: Sleep quality is a pivotal part of health and there is growing evidence on the association between gut microbiota composition and sleep quality. 5-Hydroxytryptophan (5-HTP) is known as a precursor of the sleep regulating neurotransmitter and hormone. However, efficacy of 5-HTP supplementation for improving sleep quality in older adults is unclear. Hence, the aim of this study is to assess the impact of 5-HTP supplementation on sleep quality and gut microbiota composition in older adults.

Methods: This is a single-blinded, 12-week parallel randomized controlled trial. Thirty older adults (66 ± 3 years) in Singapore were randomly assigned to either consume or not consume 100 mg 5-HTP daily. Every 4 weeks, sleep quality was assessed via both subjective (Pittsburg Sleep Quality Index) and objective (actigraphy watch) measures. A global sleep score (GSS) was obtained from the PSQI, where a GSS>5 defines as poor sleeper while a GSS≤5 defines as good sleeper. Blood serotonin level, urine melatonin concentration, gut microbiota composition and stool short chain fatty acids (SCFA) content were assessed at week 0 and 12. This study was registered in clinicaltrials.gov as NCT04078724 (https://clinicaltrials.gov/ct2/show/NCT04078724).

Results: 5-HTP supplementation showed an overall favorable effect on certain sleep quality components and an increase in serum serotonin concentration. In particular, at week 12, not good sleepers but poor sleepers with 5-HTP supplementation were able to significantly improve subjective GSS (ΔSL_5-HTP: -2.80 ± 1.10 min, p-value = 0.005). In addition, they showed an increase in microbiota diversity (Simpson_5-HTP vs. Simpson_Control: 0.037 ± 0.032 a.u. vs. -0.007 ± 0.022 a.u.; p_interaction: 0.013) and relative abundance of SCFA producing bacteria in the gut.

Conclusions: 5-HTP supplementation can improve certain sleep quality components in older adults and this benefit was more prominently observed in poor sleepers. 5-HTP was also able to improve the gut microbiota composition in poor sleepers.

Keywords: 5-Hydroxytryptophan; Gut microbiota; Melatonin; Serotonin; Sleep quality; Tryptophan.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

5-Hydroxytryptophan
Aged
Dietary Supplements
Gastrointestinal Microbiome*
Humans
Serotonin
Sleep Quality*

Substances

5-Hydroxytryptophan
Serotonin

Associated data

ClinicalTrials.gov/NCT04078724