Does Tea L-Theanine Cognition Sleep Mood Meta-Analysis work?

The current Migaku evidence database contains 2 reusable source documents for Tea L-Theanine Cognition Sleep Mood Meta-Analysis. This answer focuses on strength of evidence and what the studies can or cannot prove. - Context The bioactive compounds found in tea from Camellia sinensis, namely theanine, caffeine, and polyphenols, can potentially improve short-term and long-term health outcomes. [Payne ER (2025); evidence level 1] - Conclusions This meta-analysis provides evidence that theanine plus caffeine, and theanine alone, could be beneficial for cognitive and mood outcomes. [Payne ER (2025); evidence level 1] - Objective The aim of this study was to assess the effects of tea, theanine alone, or theanine plus caffeine on cognition, mood, and sleep outcomes, using data from randomized controlled trials (RCTs) in healthy participants. [Payne ER (2025); evidence level 1] - Failure to meet the recommended 7-9 hours of restful sleep per night is known to increase the risk of several health conditions, reason why regular and adequate sleep should be seen as a priority instead of an unnecessary commodity easily traded as required by the commitments of our busy lives. [Conti F (2026); evidence level 4] - While both the quantity and the quality of sleep can be largely improved with relatively straightforward practices dictated by good sleep hygiene, emerging research suggests that dietary and supplementation protocols focused on certain foods, nutrients, and biochemical compounds with sleep-promoting properties can act as subsidiary sleep aids in complementing these behavioral changes. [Conti F (2026); evidence level 4] Evidence levels are sorting aids, not final clinical grades. Level 1 usually indicates systematic-review style evidence, level 2 indicates randomized trials or public-health guidance, and lower levels need more cautious wording. This page is educational. People with medical conditions, pregnancy, medication use, or unusual symptoms should ask a qualified clinician before changing supplements, medication, or treatment routines.