Everything You Need to Know About L-Theanine and Camellia sinensis
Scientific Name: [L-Theanine: r-glutamylethylamide, Suntheanin] [Camellia sinensis – the Plant Containing L-Theanine; of the Theaceae Family]
Any Other Names: Theanine, Constituent of Camellia sinensis, Green Tea
Primary Constituents: L-Theanine
Country or Region of Origin: East Asia and Southwestern China
Known Uses: Reduce Stress and Anxiety, Lowers Elevated Blood Pressure, Increases Concentration and Focus, Promotes Relaxation
General History & Introduction
Camellia sinensis is better known as “tea” and is the second highest consumed beverage on the planet (Twilley & Lall, 2018). The Camellia sinensis plant grows as an evergreen shrub around 3-5 feet tall with dark, rough leaves and sweet-smelling, white flowers (Chevallier, 2016). It is typically found in India, China, and Sri Lanka, where it has established itself as a staple herbal tea even in the earliest of cultures. There are a lot of ancient, cultural rituals in many Asian countries surrounding the drinking of the herbal tea (2016). Each tea plant produces enough leaves to be picked up to 4 times within a year (Shivashankara et al., 2014).
Camellia sinensis also has a long history of use in Ayurvedic medicine (Chevallier, 2016). It has also been well-accepted throughout Indian culture as an herbal tea (2016). And although Camellia sinensis has a lot of great benefits, one of its amino acid derivatives, L-Theanine, is primarily responsible for the plant’s nootropic effects (2016). L-Theanine is well known for its favorable effects on cognitive performance, emotional state and mood, sleep, and a variety of other health benefits (Türközü & Şanlier, 2017).
Important Note: L-Theanine is a derivative of Camellia Sinensis, which is commonly used to make green tea. Both L-Theanine and Camellia Sinensis offer profound cognitive and relaxation effects, only L-Theanine is considered a nootropic and Camellia Sinensis is usually only consumed as a tea. This article will reveal the positive benefits of items, and how their effects may compare and contrast.
Nootropic Benefits of L-Theanine and Camellia sinensis
Concentration, Focus, and Cognitive Benefits (both L-Theanine and Camellia sinensis)
L-Theanine has always been used for its cognitive performance enhancing capability, however, modern studies have begun to record its significant effect on measurable attributes. For example, one study has measured the chemical’s effects on concentration and learning ability with encouraging results and future propositions for improving the chemical’s value in the brain (Vuong et al., 2011). The nootropic possesses an innate ability to increase cerebral blood flow, especially when it is used alongside caffeine (Dodd et al., 2015). This contribution to brain health is one of the main factors in its reported cognitive benefits (Dodd et al., 2015).
The nootropic provides the brain with increased subjective alertness and improved cognitive function (Giesbrecht et al., 2010). It is one of the primary nootropics benefiting from use alongside another. In other words: L-Theanine works better when it is used with Caffeine. For example, one study on the combination of L-Theanine and Caffeine found participants to have significantly improved focus and attention-spans during a “demanding cognitive task” (2010).
Reduces Stress and Anxiety, Promotes Relaxation (both L-Theanine and Camellia sinensis)
L-Theanine has been revered throughout Eastern cultures for thousands of years for its ability to reduce oxidative stress and provide focused, calming effects (Ross, 2014). These antioxidant properties are present when the plant is brewed in tea form, as well as within L-Theanine supplements (Chevallier, 2016). There are studies which have shown the primary constituent has a significant positive effect on behavior and mood (Dodd et al., 2015).
One recent, randomized, controlled-trial suggested that L-Theanine can significantly relieves stress-related ailments and promotes overall mental health (Hidese et al., 2019). And some studies suggest that L-Theanine can increase certain neurotransmitters in the brain, which are responsible for promoting relaxation and regulating mood (Nathan et al., 2006). These neurotransmitters include dopamine, serotonin, and GABA (2006).
Digestive Treatments (both L-Theanine and Camellia sinensis)
Gut Flora are microorganisms (bacteria) which live in the intestines and aide in digestion activities. Some recent research suggests that L-Theanine may have the potential to improve Gut Flora in the digestive tract while also limiting the growth and spread of harmful bacteria (Saeed et al., 2019). It is purportedly also able to reduce risks of infections within digestive organs (Li et al., 2016). Some research even suggests the chemical can entirely prevent some digestive disorders (Wang et al., 2012).
One study has suggested that drinking unfractionated green tea can help prevent gastrointestinal disorders (Koo & Cho, 2004). More recent research has revealed the polysaccharides from Camellia sinensis flowers are able to regulate gut health (Chen et al., 2019). This same study suggested that the plant also ameliorated cyclophosphamide-induced immunosuppression (2019).
Other Benefits (both L-Theanine and Camellia sinensis)
Camellia sinensis herbal tea has long been used to treat a variety of skin and inflammation conditions (Chevallier, 2016). It also offers many anti-bacterial benefits. The constituent L-Theanine is great for regulating and improving the quality of sleep (Türközü & Şanlier, 2017). It has also been proven to have positive effects on cancer, cardiovascular disease, and obesity. The nootropic can even reduce the symptoms of the common cold (2017). Some research has shown that regular consumption of Camellia sinensis can reduce risk of pancreatic cancer (Wang et al., 2012). Similarly, L-Theanine has been shown to have the potential to prevent and manage many different types of cancers (2012).
And one study revealed L-Theanine’s potential to improve immune function (Li et al., 2016). The chemical has been shown to possess an ability to improve nutrient absorption in the gut (Yan et al., 2017). Vitamins and minerals are literally absorbed better with L-Theanine, improving overall health (2017).
Dosing and Usage Information
Normally, only the leaves and buds of the Camellia sinensis plant are used, and this includes in the extraction of primary constituent, L-Theanine (Chevallier, 2016). Dietary supplements typically contain a maximum of 400 mg of L-Theanine extract.
Although more research is still required to draw ultimate consensus, one recent study on the safety and effects of using L-Theanine on a regular basis revealed the chemical as reliable and generally accepted as safe, even when consumed in larger quantities (Türközü & Şanlier, 2017). That said, while uncommon, some side effects may include headaches, irritability, and nausea (Giesbrecht et al., 2010).
Other Important Information
Sometimes Camellia sinensis is mixed with other herbs to create intricate herbal tea concoctions. Cinnamon is one of the most popular additives (Chevallier, 2016). The plant is used to produce all kinds of teas, including the traditional black, oolong, and green teas (Shivashankara et al., 2014).
The primary constituent responsible for the nootropic benefits of the tea, L-theanine, is also responsible for the flavorful taste of the tea (Vuong et al., 2011).
L-Theanine and its parent plant, Camellia sinensis, are extremely effective brain-boosters and have been well-known throughout many cultures as such. They also offer relaxation-inducing effects. L-Theanine’s nootropic benefits are constantly being investigated and backed by a growing archive of studies and empirical data. For this reason, L-Theanine has become one of the more popular nootropics, especially in Western cultures. And its effects on cognitive function and stress make it a great addition to most nootropic stacks.
A Note from NooFiles
This article is intended to be used for information only. We want to remind you that consulting your physician is recommended before adding any dietary supplement of any kind to your daily regimen.
Chen, D., Chen, G., Ding, Y., Wan, P., Peng, Y., Chen, C., Ye, H.,, Zeng, X., and Ran, L. (2019). Polysaccharides from the flowers of tea (Camellia sinensis L.) modulate gut health and ameliorate cyclophosphamide-induced immunosuppression. Journal of Functional Foods. Vol. 61. DOI: https://doi.org/10.1016/j.jff.2019.103470
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