Effects of 5-hydroxytryptophan on distinct types of depression: a systematic review and meta-analysis

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#5-hydroxytryptophan #antidepressive-agents #clinical-trials-as-topic #cohort-studies #cross-sectional-studies

Effects of 5-hydroxytryptophan on distinct types of depression: a systematic review and meta-analysis

Javelle et al., 2020 | Nutr Rev | Meta Analysis

Citation

Javelle Florian, Lampit Amit, ... Zimmer Philipp. Effects of 5-hydroxytryptophan on distinct types of depression: a systematic review and meta-analysis. Nutr Rev. 2020-Jan-01;78(1):77-88. doi:10.1093/nutrit/nuz039

Abstract

CONTEXT: Serotonergic dysfunction, including reduced central serotonin levels, is associated with different psychiatric syndromes, including depression. As a serotonin precursor, 5-hydroxytryptophan has long been used as a nonpharmacological treatment for depression. OBJECTIVE: A systematic review and meta-analysis was conducted to determine the antidepressant effects of 5-hydroxytryptophan in depressed patients. DATA SOURCES: MEDLINE (via PubMed) and Google Scholar were searched from inception to May 2018. DATA EXTRACTION: Thirteen investigations were included in the systematic review (using PRISMA guidelines), and 7 in the full meta-analysis (pre-registered on PROSPERO: CRD42018104415). DATA ANALYSIS: Analyses revealed a depression remission rate of 0.65 (95% confidence interval [CI], 0.55-0.78; remission rate [k] = 13), and this was confirmed by the questionnaire results, which revealed a large Hedges' g (1.11; 95%CI, 0.53-1.69). Methodological variability (in treatment duration, type of depression studied, experimental design, 5-hydroxytryptophan dosage) contributes to heterogeneity in the results (I2 = 76%, τ2 = 0.379). In addition, the OHAT (Office of Health Assessment and Translation risk of bias rating) tool suggested that, on the whole, current studies are relatively weak (few include placebo groups). CONCLUSION: Further trials should overcome these limitations by using placebo-controlled studies that include patients with well-defined depression diagnoses, along with strong characterization of psychological and physiological patient characteristics.

Key Findings

Further trials should overcome these limitations by using placebo-controlled studies that include patients with well-defined depression diagnoses, along with strong characterization of psychological and physiological patient characteristics.

Outcomes Measured

  • depression

Population

Field Value
Population well
Sample Size See abstract
Age Range See abstract
Condition depression

MeSH Terms

  • 5-Hydroxytryptophan
  • Antidepressive Agents
  • Clinical Trials as Topic
  • Cohort Studies
  • Cross-Sectional Studies
  • Depression
  • Humans

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Systematic Review
  • Vertical: five-htp-mood

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09