The amino acid l-theanine is one of the most versatile of all the naturally sourced nootropics. Sourced from Camellia sinensis (tea leaves) it is most apparent in green tea. L-theanine is also present in much smaller doses in black tea and can also be found in guayusa. L-theanine is considered calming but is not actually sedative. L-theanine is not an essential amino acid and is not regularly found in an average diet. L-theanine is especially interesting due to the fact that it has the ability to increase focus without being overly stimulating. As a result it’s a popular addition to the caffeine-theanine stack which is recommended for many who are interested in taking their first steps towards nootropic enhancement.
L-theanine is structurally similar to glutamine. Glutamine is the source of both GABA, the primary inhibitory neurotransmitter and glutamate, the primary excitatory neurotransmitter. It is orally active and similar to lemon balm as far as relaxation, though without the added sedative property. Some studies show it may lessen the perception of stress while focusing attention. Though it is not sedative, some anecdotal reports suggest it may assist in calming an over-stressed mind which could support healthy sleep cycles.
Considering the fact that it is slightly relaxing but also a focusing compound, it is often a great supplement to stack with more energizing or stimulating nootropics. 200 mg of theanine combined with an equal amount of caffeine is found to be especially synergistic. The actual mechanism of the caffeine and theanine synergy is fairly interesting in and of itself. Caffeine’s primary action as an energizing and stimulating substance is due to the fact that the caffeine molecule closely resembles that of the neurotransmitter adenosine.
Adenosine is a neurotransmitter that is released when the body and brain have done work. It is basically the chemical signal that you’re tired after having expended effort. When you ingest caffeine, the caffeine molecules fit into the receptor slot for adenosine so the adenosine that is released is blocked. Theanine works in a nearly opposite way. Theanine is shaped very similar to the neurotransmitter glutamate. Glutamate is not only one of the most prominent of all neurotransmitters, it’s the primary excitatory neurotransmitter.
Neurotransmitters are generally either inhibitory or excitatory. Excitatory neurotransmitters influence the firing of neurons and inhibitory neurotransmitters act to block over-firing neurons. Since theanine is very similarly structurally composed to glutamate, it sits in the glutamate receptor and blocks its actions in a similar way that caffeine blocks adenosine. So caffeine fakes out the mind by convincing it that it isn’t tired and theanine can calm the over-firing neurons associated with anxiety and stress.
L-theanine has another inhibitory effect as well. In addition to blocking glutamate, the excitatory neurotransmitter, it also stimulates production of GABA which is our brain’s natural calming chemical compound. Unlike GABAergic drugs such as the benzodiazepines, L-theanine produces a calming effect without any subsequent motor impairment, inebriation or sleepiness.
L-Theanine Health Benefits
In addition to the focusing and calming effects of l-theanine, are several other health benefits. Many of the health benefits associated with green tea are due to antioxidants and flavonoids, but l-theanine itself seems to have some interesting health benefits unrelated to the other components of green tea. L-theanine may prevent the dangerous rise in blood pressure that can accompany high stress.
The surge in blood pressure that accompanies stress wreaks havoc on your arteries, so l-theanine is a good choice to keep stress and blood pressure level. L-theanine may also have a potential to protect against the dangerous excitotoxicity that results from over-firing neurons. Excitotoxicity is a major player in several forms of age related cognitive decline. Scientists are currently researching l-theanine’s potential therapeutic benefit related to long-term neurodegenerative disorders, stroke.
In addition to being a calming, focusing compound it possesses some neuroprotective and rejuvenative, life-extension related effects not to be overlooked. L-theanine is even being looked into as a possible adjunctive therapy for those living with schizophrenia, post-traumatic stress disorder (PTSD) and even substance abuse and dependence. Stress is a killer, both for the body and the brain. As a result, reducing the blood levels of stress hormones may improve learning and memory by improving the reaction to oxidative and environmental stress and the endogenous toxins (catecholamines and “fight or flight” hormonal byproducts) that can cloud decision making and affect memory and recall as well.
Chronic glutamate-driven excitotoxicity has been implicated as a factor in Alzheimer’s, Parkinsons, Huntington’s disease and amyotrophic lateral sclerosis (ALS). In animal trials, l-theanine is suggested to combat the long-term effects of such glutamergic excitotoxicity. According to a study utilizing lab rodents l-theanine “significantly attenuated” the behavioral, biochemical and mitochondrial enzyme activities leading to the conclusion by the researchers that “L-theanine has neuroprotective activity against 3-nitroproprionic acid induced neurotoxicity.”
Some studies even suggest that l-theanine may offer biochemical and structural support to brain cells damaged by aluminum or other toxic chemicals. This is postulated as yet another potential means that l-theanine might act as a neuroprotective agent. In addition to its potential to improve cognition and slow age related decline, l-theanine has also been tapped as a potential aid to those working on cardiac health. Ischemic strokes occur due to a sudden blockage of blood to the brain. This leads to chemical stress, extreme excitotoxicity and brain cell death. In recent studies l-theanine has been suggested as an aid at preventing strokes as well as attenuating the damage of strokes if and when they do occur.
L-theanine improves nitric oxide production in the endothelial (artery-lining) cells. Nitric oxide is an important signal to endothelial cells that allows them to constrict or relax in response to necessary blood flow. L-theanine has also been shown to prevent reperfusion of blood, the refilling of blood occuring after loss of circulation due to stroke. Ischemia-reperfusion results in massive amounts of glutamate being spilled out which often leads to excitotoxicity which in turn can cause massive neuronal death. Some studies have shown that administration of l-theanine up to 12 hours after a stroke may protect brain cells and reduce the overall size of the damaged portions. In fact, supplementation up to 24 hours after a stroke may improve overall neurological function and recovery times.
On top of all this, theanine, unlike many supplements, vitamins, herbs and nootropics, doesn’t even taste bad. On the contrary, theanine’s flavor, described by the Japanese as “umami,” is mild and pleasant. If you want to try a caffeine theanine blend, you can easily weigh out your desired dosage of l-theanine right into your coffee cup in place of creamer.
L-theanine is a naturally sourced nootropic, but it’s still important to stay in the recommended dosage range with this and all supplements. 200-400mg dosages up to three times a day shouldn’t be excessive. Remember to always consult with your personal care practitioner before undertaking any major dietary, exercise or supplementation regimen.