L-Theanineand Focus And Attention.
Evidence gradeB
ImpactSmall
Confidencemedium
Imported rating. This grade comes from SuppCo and has not been independently reviewed. It describes research, not a product, and it is not medical advice.
The rating
- Direction
- Favourable
- Rated by
- SuppCo
- Observed
- 28 September 2026
Studies behind it
Dose–response effect of L-theanine on psychomotor speed, sustained attention, and inhibitory control: a double-blind, placebo-controlled, crossover studyT. Dassanayake · Nutritional Neuroscience2022L-theanine improves neurophysiological measures of attention in a dose-dependent manner: a double-blind, placebo-controlled, crossover studyT. Dassanayake · Nutritional Neuroscience2020Effects of L-theanine on attention and reaction time responseA. Higashiyama · Journal of Functional Foods2011