L-Theanine and Stress
A closer look at what the research shows about L-Theanine and its effects on stress, relaxation, and cognitive performance.
About the study
This randomized, placebo-controlled crossover study investigated whether taking 200 mg of L-theanine per day for four weeks could influence stress-related symptoms and cognitive function in healthy adults.
Thirty participants took either L-theanine or placebo for four weeks before crossing over to the other condition.
Researchers assessed measures including stress-related symptoms, sleep quality, verbal fluency, and executive function.
The study reported reductions in several stress-related questionnaire scores and improvements in verbal fluency and executive function during the L-theanine condition.
Key takeaway
200 mg/day of L-theanine was associated with improvements in several measured stress-related and cognitive outcomes in this small study.
That provides human evidence worth considering, but it does not establish that every person will experience the same effect.
What the research found
Important context
SUPRACALM contains 400 mg of L-theanine per serving, so this study does not establish that 400 mg/day produces the same result.
A separate 2024 randomized trial studied 400 mg/day for 28 days in 30 healthy adults with moderate stress. It found some within-group improvements, but the authors also called for larger and longer randomized trials to address variability and placebo effects. The trial was conducted using AlphaWave® L-theanine, and several authors were employees of companies involved with the ingredient.
Study details
What this means for SUPRACALM: The research gives us evidence about L-theanine as an individual ingredient. It does not show that the finished SUPRACALM formula has been clinically tested, or that every person taking 400 mg will experience the same outcome. Our goal is to show you the research behind the ingredient without turning ingredient research into a product-level promise.
