Comparative Efficacy of 5-Hydroxytryptophan Delivered via Capsule or Functional Food Bar on Mood, Sleep, and Salivary Cortisol: A Randomised, Double-Blind, Placebo-Controlled Trial

Rachel Nye Venter, Robert EC Wildman, Mark Haub, Melissa Kirby Riddell* and Divya Chandradhara

Objective: Poor sleep quality and elevated psychological distress are highly prevalent in young adults. This randomised, double-blind, placebo-controlled, four-arm parallel group clinical trial evaluated the comparative efficacy of 5-hydroxytryptophan (5-HTP) derived from organic Griffonia simplicifolia delivered via a traditional capsule versus a functional food snack bar on mood, sleep quality, and physiological stress markers.

Methods: Eighty healthy adults aged 18-40 years with self-reported poor sleep quality and low mood were randomised in a 1:1:1:1 ratio to receive a Placebo Capsule, Placebo Bar, 5-HTP Capsule (150 mg/day), or 5-HTP Bar (150 mg/day) for 25 days. Outcomes included the Depression Anxiety Stress Scales-21 (DASS-21), the Pittsburgh Sleep Quality Index (PSQI), and salivary cortisol. Participants and all study personnel involved in conducting or evaluating the trial remained unaware of the treatment assignments. Efficacy was evaluated using an Intention-to-Treat (ITT) framework, with Last Observation Carried Forward (LOCF) used for missing follow-up data and ANCOVA models used to adjust for baseline values.

Results: Both active 5-HTP groups demonstrated improvements in DASS-21, PSQI, and salivary cortisol outcomes by Day 25. Placebo groups showed smaller mean changes from baseline: DASS-21 decreased by 2.35 points in PLA-CAP and 1.75 points in PLA-BAR, PSQI decreased by 1.60 points in each placebo group, and morning and evening cortisol changed by no more than 0.11 and 0.08 µg/dL, respectively. Baseline-adjusted ANCOVA models showed a significant overall treatment group effect. Supportive pairwise comparisons of the unadjusted Day 25 scores showed significant differences between each active 5-HTP group and its format-matched placebo group (p < 0.001). No statistically significant differences in clinical response were observed between the active capsule and functional food bar delivery formats for DASS-21 or PSQI outcomes.

Conclusions: Daily supplementation with 150 mg/day of 5-HTP is associated with significant improvement in mood and sleep quality in young adults, with supportive reductions in salivary cortisol. Under the conditions of this study, the functional food bar produced an observed clinical response comparable to the traditional capsule format. Trial registered with the Clinical Trials Registry-India (CTRI/2024/02/063100).

Keywords:

Published on: Jul 18, 2026 Pages: 1-8

Full Text PDF Full Text HTML DOI: 10.17352/jfsnt.000059
CrossMark Publons Harvard Library HOLLIS Search IT Semantic Scholar Get Citation Base Search Scilit OAI-PMH ResearchGate Academic Microsoft GrowKudos Universite de Paris UW Libraries SJSU King Library SJSU King Library NUS Library McGill DET KGL BIBLiOTEK JCU Discovery Universidad De Lima WorldCat VU on WorldCat