Your shopping cart is empty!
FREE SHIPPING OVER 35€
WELCOME COUPON €5 "CIAO5"
The L-theanine is an amino acid present in nature almost exclusively in tea, particularly in Camellia sinensis, the plant from whose leaves the famous infusion is obtained, especially in green tea and matcha tea. This important molecule, often associated with glutamine (in fact, its name is N-ethyl-L-glutamine) and derived from glutamic acid, as their chemical structure is very similar, differs from other amino acids in not being proteinogenic, meaning it is not incorporated into the chains that make up proteins.
Amino acids are molecules containing an amino group, a carboxylic group, and a chain that varies for different amino acids. Tea contains several amino acids, but only a portion of them are water-soluble and are retained in the infusion: theanine makes up 60% of this quantity of amino acids and is responsible for the recognizable sweet and umami taste of green tea, in which it is more abundant.
Theanine is a very important molecule, studied recently (especially since the 1950s) for its psychoactive properties, as it is able to cross the blood-brain barrier and induce alpha waves (or alpha rhythm) in the brain, usually recorded when the subject is awake but completely relaxed.
In this article, we want to delve into the extraordinary relaxing properties of theanine, as well as its other various health effects, discovering in which teas in particular it can be found and what benefits it has for our body.
The main source of theanine is tea, especially green tea, although traces have also been found in other species of the genus Camellia and in some varieties of mushrooms (Boletus badius). Tea represents the most common food in which it is possible to find L-theanine, which is therefore a substance as beneficial as it is difficult to find in nature.
Theanine is an amino acid that develops in the tea plant when the leaves are very young. As the plant undergoes chlorophyll photosynthesis thanks to exposure to the sun, the L-theanine transforms into catechins, the antioxidants of tea. Chemically, in the tea plant, there will be a greater amount of theanine in the younger and lighter leaves found at the top of the plant compared to the older lower leaves that have been exposed to the sun longer and have undergone photosynthesis and developed more chlorophyll. This does not mean that the first tea leaves are completely devoid of antioxidants: as the leaf remains exposed to the sun, however, it will lose theanine and gain antioxidants.
Not many people know that theanine affects the taste of tea: the more theanine is present in the leaf, the sweeter the tea will be. For this reason, a good matcha is recognizable by its characteristic sweet and velvety taste, due to the high levels of theanine. Few people know that theanine dissolves better in cold water: for this reason, you can opt for cold green tea to enjoy its benefits.
In pharmacies, L-theanine produced for commercialization is obtained through bacterial fermentation.
Matcha for Sale Online at Terza Luna
Among the green teas richest in theanine, we find matcha tea and gyokuro tea, known for their sweetness and balance. But why do these two teas have more theanine than other green teas?
The cultivation methods, the timing of leaf picking, and the climate are all factors that influence the chemical composition of the leaves, and therefore also the levels of theanine.
Matcha and gyokuro tea (like Gyokuro available at Terza Luna) have high levels of this amino acid mainly due to the traditional cultivation method in Japan called kabuse: with this cultivation, tea plants are shaded under tents, about 15 days before harvesting. Shading protects the plant from the sun: the leaves will produce less chlorophyll but will still mature. This way, a tea leaf rich in L-theanine is obtained, as well as caffeine and antioxidants.
Similarly, first flush leaves harvested in early spring, the so-called first flush, of any green tea (for example, sencha tea) will be richer in theanine compared to second flush leaves, harvested later, which have undergone more photosynthesis. Youthful tea leaves are consequently, thanks to their higher theanine content, more delicate, sweet, balanced, and therefore more precious, and will have fewer polyphenols, a characteristic of bitter taste.
But what is theanine for and why is it considered an indicator of tea quality? As already outlined, theanine has numerous properties: in particular, it is an amino acid that crosses the blood-brain barrier and increases alpha rhythm, the basal rhythm of electroencephalography in which you are awake but in a completely relaxed state. Brain waves are recorded through electroencephalogram that captures electrical impulses on the scalp: the rhythm and the different frequency and amplitude of the waves correspond to different brain activity, from wakefulness, to relaxation, to sleep. Alpha waves, or Berger's rhythm, are characterized by slow oscillations with a frequency of 8-13 Hz and indicate an awake, alert but relaxed adult and free from thoughts. Generally, this condition is nullified by visual or mental stimuli.
Experimental studies have shown that the administration of theanine in subjects with anxiety issues generated alpha brain waves 30 minutes after intake, corresponding to the absorption times of L-theanine and reaching brain tissue.
Several studies have also shown how the intake of theanine helps reduce physical and mental stress, inducing a feeling of relaxation but not drowsiness, thus improving attention and concentration. Thanks to the combined effect with caffeine present in tea leaves, theanine helps improve concentration and cognitive functions by counteracting the negative and anxiolytic effects of caffeine.
In general, based on the evidence found in scientific literature, the following properties are attributed to L-theanine:
Generally, alpha waves are recorded in that intermediate twilight where one is relaxed but not asleep, a state very favorable to the body and brain, which can also be achieved through meditation and breathing practices. It is the state experienced just before falling asleep, a state of extreme calm: conversely, a low level of alpha waves translates into anxiety, stress, and insomnia. Studies have shown how theanine stimulates the production of cerebral alpha waves, and therefore induces a state of relaxation and calm capable of counteracting anxiety, agitation, stress, and hypertension.
The exact mechanisms of theanine's reaction with serotonin levels are not known, but the effect produced by theanine in the brain is attributed to the increase in GABA production (gamma-aminobutyric acid), an important neurotransmitter that regulates the neuronal excitability of the nervous system, and dopamine levels in the brain. These mechanisms are precisely attributed to the relaxing, antidepressant, and anti-stress properties.
Some researchers believe that L-theanine regulates the excitotoxicity of glutamic acid—a precursor of theanine itself, as well as the neurotransmitter GABA—which high neuronal levels seem to favor headaches, insomnia, and excitement in addition to potentially causing neuronal damage and Alzheimer's disease. Studies conducted on laboratory rats have also shown neuroprotective effects of L-theanine.
L-theanine is also associated with immunomodulatory effects. It is believed that theanine improves the immune defenses' response to viruses, bacteria, and other infections by enhancing the activity of gamma delta T lymphocytes, which mediate innate immunity and play a role in antigen recognition. This action, however, requires further studies, as existing ones, while showing a correlation between theanine and immune response, have been conducted on limited samples.
Often, theanine is confused with caffeine, as its name is similar to that of theine, as caffeine is called in tea. In reality, they are two distinct molecules with different functions and effects, whose correlation is very important.
We have seen how the relaxing effect given by tea despite the caffeine content is attributable precisely to L-theanine, which counteracts the stimulating action of the central nervous system of theine, allowing for a state of calm but not drowsiness, a relaxed wakefulness in which the side effects associated with caffeine are modulated such as anxiety, tremors, nervousness, hyperexcitability, and tachycardia.
