A handful of supplements have been shown to enhance cognitive function but one stands out from the crowd by virtue of how quickly users see results. L-theanine was found to enhance working memory and attention after a single dose in one study.
L-theanine is an amino acid found naturally in some mushrooms, green and black teas. It is also available in supplement form.
The compound can benefit a person’s cognitive functions after a single dose, one study concluded.
L-theanine is an amino acid found naturally in some mushrooms, green and black teas
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Sixty-nine Japanese men and women aged between 50 and 69 were recruited for the study, published in the Journal of Medicinal Food.
Evaluations were performed before the intervention, after a single dose of L-theanine, and after 12 weeks of regular intake.
What did the researchers find out?
The single dose of L-theanine reduced the reaction time to attention tasks, and it increased the number of correct answers and decreased the number of omission errors in working memory tasks.
"In conclusion, our study indicated that l-theanine may contribute to improving attention, thus enhancing working memory and executive functions," the study authors wrote.
Since the researchers focused on a specific cohort, it is unclear how generalisable the findings are, but other studies have pointed to the cognitive benefits of L-theanine.
A small study in Neuropharmacology, participants who took 100 milligrams of L-theanine before a monitored two-hour task period made fewer errors during that time than those who received a placebo.
There is no established dose recommendation but studies often use daily doses between 100 and 250 milligrams.
In 2016, researchers reviewed the existing research on the benefits of L-theanine and concluded that this compound could benefit a person’s mental and physical health.
Studies often use daily doses between 100 and 250 milligrams
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They noted that it seems to have neuroprotective effects, which improve brain function.
However, not all research has found that L-theanine can improve people’s cognitive abilities. More high-quality research is needed to clarify the effects of this compound on people’s mental functions.
