Evidence supporting the use of: L-theanine
For the body system: Specific Neurotransmitters

Links: Go back one page, Tool main page, Ingredients list, Health conditions list, Body systems list

Synopsis

Source of validity: Scientific
Rating (out of 5): 3

L-theanine is an amino acid found naturally in tea leaves, especially green tea. Its use to support the "Specific Neurotransmitters" body system is justified by a growing body of scientific research. L-theanine readily crosses the blood-brain barrier and is known to influence several neurotransmitters, notably increasing levels of gamma-aminobutyric acid (GABA), dopamine, and serotonin. These neurotransmitters are associated with relaxation, mood regulation, and stress reduction.

Multiple clinical studies have demonstrated that L-theanine supplementation can promote relaxation without sedation, reduce stress, and improve attention. For example, randomized controlled trials have shown that doses of 200–400 mg of L-theanine can increase alpha brain wave activity, which correlates with a state of relaxed alertness. Other studies have shown improvements in cognitive performance, likely mediated by its effects on neurotransmitter modulation.

However, while the evidence is promising, most studies are small and of short duration. The precise mechanisms by which L-theanine affects neurotransmitter systems are still being elucidated, and more large-scale, long-term trials are needed to confirm its efficacy and optimal dosing. Nevertheless, the current scientific evidence supports the use of L-theanine for modulating neurotransmitter activity, particularly in the context of relaxation, stress, and attention.

More about l-theanine
More about Specific Neurotransmitters