L-Theanine and Improved Daytime Dysfunction

• The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis.

  • 2025-06
  • Meta-Analysis · n = 897
  • Sleep medicine reviews 81
  • • Amanda Bulman
    • Nathan M D'Cunha
    • Wolfgang Marx
    • Murray Turner
    • Andrew McKune
    • Nenad Naumovski

  • PubMed: 40056718
  • DOI: 10.1016/j.smrv.2025.102076

  3 Insights on

  • Improved Daytime Dysfunction

  • High evidence
  • Mixed

  subjective daytime dysfunction (SMD = 0.33, 95 % CI [0.16, 0.49], p < 0.001; n = 9 studies)

  Effect

  Beneficial

  Effect size

  Moderate

  Significant

  Yes