The combined effects of L-theanine and caffeine on cognitive performance and mood
The combined effects of L-theanine and caffeine on cognitive performance and mood
Owen et al., 2008 | Nutr Neurosci | Rct
Citation
Owen Gail N, Parnell Holly, ... Rycroft Jane A. The combined effects of L-theanine and caffeine on cognitive performance and mood. Nutr Neurosci. 2008-Aug;11(4):193-8. doi:10.1179/147683008X301513
Abstract
The aim of this study was to compare 50 mg caffeine, with and without 100 mg L-theanine, on cognition and mood in healthy volunteers. The effects of these treatments on word recognition, rapid visual information processing, critical flicker fusion threshold, attention switching and mood were compared to placebo in 27 participants. Performance was measured at baseline and again 60 min and 90 min after each treatment (separated by a 7-day washout). Caffeine improved subjective alertness at 60 min and accuracy on the attention-switching task at 90 min. The L-theanine and caffeine combination improved both speed and accuracy of performance of the attention-switching task at 60 min, and reduced susceptibility to distracting information in the memory task at both 60 min and 90 min. These results replicate previous evidence which suggests that L-theanine and caffeine in combination are beneficial for improving performance on cognitively demanding tasks.
Key Findings
These results replicate previous evidence which suggests that L-theanine and caffeine in combination are beneficial for improving performance on cognitively demanding tasks.
Outcomes Measured
- Requires manual extraction
Population
| Field | Value |
|---|---|
| Population | healthy volunteers |
| Sample Size | 27 |
| Age Range | See abstract |
| Condition | mood |
MeSH Terms
- Adult
- Affect
- Attention
- Caffeine
- Cognition
- Cross-Over Studies
- Double-Blind Method
- Drug Interactions
- Female
- Flicker Fusion
- Glutamates
- Humans
- Male
- Placebos
- Time Factors
Evidence Classification
- Level: Rct
- Publication Types: Journal Article, Randomized Controlled Trial
- Vertical: l-theanine-focus
Provenance
- PMID: 18681988
- DOI: 10.1179/147683008X301513
- PMCID: Not in PMC
- Verified: 2026-04-09 via PubMed E-utilities API
Source extracted via PubMed E-utilities API on 2026-04-09