L-Theanine – What it is

Theanine /ˈθənn/, also known as L-γ-glutamylethylamide and N5-ethyl-L-glutamine, is an amino acid analog of the proteinogenic amino acids L-glutamate and L-glutamine and is found primarily in particular plant and fungal species. It was discovered as a constituent of green tea in 1949 and in 1950 was isolated from Gy Okoro leaves, which have high theanine content.[4]Appearance of the name “theanine” without a prefix is understood to imply the Lenantiomer, which is the form found in fresh teas and in some, but not all dietary supplements. The opposite Denantiomer has far less studied pharmacologic properties, but is present in racemic chemical preparations, and substantially in some studied theanine supplements.

As an analog of glutamate and glutamine, the theanine in common preparations is absorbed in the small intestine after oral ingestion; its hydrolysis is to L-Glutamate and ethylamine occurs in both the intestine and liver. It can also cross the blood–brain barrier intact, and register pharmacological effects directly.

In Japan, L-Theanine has been approved for use in all foods, including herb teas, soft drinks, desserts, etc., with some restrictions applying to infant foods.[5][6] It provides a unique brothy or savory (umami) flavor to green tea infusions. As an ingredient, it is generally recognized as safe (GRAS) by the Food and Drug Administration (FDA), and is sold as a dietary supplement in the US. However, the German Federal Institute for Risk Assessment, an agency of their Federal Ministry of Food and Agriculture, has objected to the addition of isolated theanine to beverages.

The European Food Safety Authority EFSA advised negatively on health claims related to L-Theanine and cognitive function, alleviation of psychological stress, maintenance of normal sleep, and reduction of menstrual discomfort.[7]Therefore, health claims for L-Theanine are prohibited in the European Union.


L-Theanine – What it Does

L-Theanine can cross the blood-brain barrier and positively affect brain chemistry, scientists investigated its mood-modulating effects. The results of those studies have led to L-Theanine being patented as a mood enhancer.22 How it works is not completely understood, but one thing researchers have discovered is that L-Theanine changes levels of amino acids affecting serotonin and other neurotransmitters in the brain.  Researchers in Japan gave volunteers 200 mg of L-theanine daily and recorded their sleep patterns. The L-Theanine didn’t cause the subjects to sleep longer, but it did cause them to sleep better. It was documented that sleep quality, recovery from exhaustion, and refreshed feelings were all enhanced by L-Theanine. Those taking L-Theanine felt like they slept longer than they actually did.


L-Theanine – What it “Means”

The properties of L-theanine can be summed up as being a relaxing agent without sedation (relative to something like lemon balm which relaxes but may also sedate) and is also implicated in reducing the perception of stress and slightly improving attention. While L-theanine does not appear to induce sleep, it may (quite weakly) help with sleep although its potency suggests it may not be a good first line treatment for this.

Interestingly, the relaxing and attention promoting properties of L-theanine coupled with the lack of sedation may L-Theanine have its most significant supplemental role in attenuating the ‘edge’ of many stimulants. A combination of L-Theanine with Caffeine (200mg each) is noted to be synergistic in promoting cognition and attention.


Disclaimer: Please do not substitute our information for your own due diligence.  Research and understand this product and what it can do for you and be responsible for your body’s limitations. We are not responsible for any adverse reactions to our products as there may be unknown contraindications when combining with alcohol or other drugs.  This product is not intended to diagnose, treat, cure or prevent any disease. These statements have not been evaluated by the Food & Drug Administration. If you have any medical conditions, please consult a medical professional before buying.



Smart Drugs for Smart People