Everything You Need to Know About L-Theanine
6 Minute Read

When life gets too stressful, we can start feeling irritated, anxious and unable to focus. That’s why finding something to help recalibrate and restore our minds back to balance is vital. Some people manage stress with meditation, exercise, practicing a creative hobby, or reading. For others, it may be something as simple as enjoying a cup of tea after a long day.


Speaking of tea, Japanese scientists wanted to uncover what made green tea so healthy, so began clinical research into green tea’s mechanisms a few decades ago. And they’ve learned a lot since then. A 2010 review of the scientific literature on green tea showed a complex chemical composition of proteins, enzymes, amino acids, alkaloids, polyphenols, minerals, vitamins, and many other compounds. One of the identified amino acids, L-theanine, stood out amongst the rest. And so research began on this nootropic’s potential to reduce anxiety and help people cope with stress.


So, what exactly is L-theanine? Can it really help you manage stress and ease anxiety? And does this naturally-derived nootropic have other benefits?


What is L-Theanine?

L-theanine is a water-soluble amino acid that belongs to the family of bioactive, plant-sourced compounds called nootropics. Nootropics are mainly used to improve cognitive performance, but some compounds can also promote wakefulness and boost energy levels. Others, like L-theanine, also have adaptogenic properties that help us better manage stress.


L-theanine is a nootropic compound found in green and black tea leaves, as well as some bioactive mushrooms. It is responsible for the savory, umami taste of green tea and the many health benefits of this beverage. Green tea is perhaps the oldest known tonic for calm, immunity and overall physical health, and L-theanine is an integral part of that heritage.


What Are the Benefits of L-Theanine?

Regular green tea consumption has many benefits, and scientists identified L-theanine as one of the reasons. This chemical compound was first isolated in 1949 from the leaves of the tea plant (Camellia sinensis). Since then, use of this nootropic has quickly proliferated and become a functional food additive in Japan, as well as an essential constituent of many supplements, including plant-powered energy powders like MTE. Common uses of L-theanine include:


  • Manage stress
  • Reduce symptoms of anxiety and depression
  • Improve sleep
  • Boost cognitive performance and attention
  • Balance mood
  • Improve immune response


Because of the diverse potential to improve various aspects of our health, L-theanine has become a common ingredient of many functional beverages and herbal drink mixes. You can find it in virtually all types of holistic wellness powders and energy drinks for things like hangxiety, stress-relief, anti-procrastination, mood, and mental focus.


L-theanine isn’t just a wellness fad; it’s got a body of science to back up its claims. And that’s why we’ve included it in our MTE energy powder supplement formulation.


Here’s what science has to say about the benefits of L-theanine:


L-Theanine May Help People Manage Stress

L-theanine is likely one of the reasons a cup of green tea helps you relax after a stressful day. In a placebo controlled study, scientists investigated how consuming L-theanine supplements affected mental state and focus. They discovered that the group that consumed L-theanine daily presented more alpha brainwave activity.


Why is that cool? Well, there are five different types of brainwaves that become dominant when we are asleep, focused, relaxed, focused, and active. Alpha brainwaves are connected with feelings of relaxation without drowsiness. What’s even more interesting about this study is that it was successfully replicated, and that second study had complementary results.


What this means is that clinical data indicates L-theanine can boost your ability combat stress while allowing you to stay alert and focused. That’s why L-theanine is such a useful ingredient in a stress-relief drink for work and studying. You’ll be able to slip into that zoned-in vibe without phasing out and falling asleep at your desk.


Another study on the nootropic qualities of this powerful amino acid measured stress responses in a group who took an L-theanine supplement and a group who’d had a placebo. The results of this study found a single dose of L-theanine increased alpha brainwave activity and decreased saliva cortisol levels, which are important indicators of stress reduction. An increase in alpha activity in the frontal region also supports L-theanine’s indication as a pro-concentration nootropic.


Studies on L-Theanine Suggest it Eases Anxiety

2016 systematic review identified five studies investigating L-theanine’s ability to reduce acute anxiety and stress. Researchers found that supplementation with this nootropic helped people cope better in stressful situations and reduce anxiety. And although studies had small sample sizes, these findings indicated that L-theanine could be one of the best nootropics for anxiety.


More recent trials confirmed these findings, showing that supplementation with L-theanine helped people feel less stressed, anxious, and depressed. General anxiety and depression are all too common in today’s fast-paced, high-stress world, so the idea that there may be natural alternatives to synthetic pharmaceuticals is intriguing to say the least. Why take a xanax if you notice that same calming effect from a drink containing L-theanine?


L-Theanine Could Battle Depression Symptoms

In addition to helping people overcome stress and anxiety, it appears that L-theanine could be one of the crucial nootropics for fighting symptoms of depression. Studies in mice discovered that supplementing with L-theanine balanced the levels of serotonin, dopamine and norepinephrine in key areas of the brain. That’s important because regulation of these neurotransmitters plays a vital role in depression management. In this particular study, this translated to mice exhibiting less depressive-like behaviors.


We only have a few studies examining the effects of L-theanine on depression in humans, but the results show great promise. For example, results from a 2017 open-label study with serious limitations showed that supplementing with L-theanine positively impacted people with major depressive disorder. They experienced improvements in depression and anxiety symptoms, sleep quality and cognitive performance.


In a 2019 randomized, placebo-controlled trial on L-theanine’s effects on depressive symptoms, 30 healthy middle-aged adults were split into a placebo group and a 200mg L-theanine per-day group. After 4 weeks of daily consumption, the L-theanine group had better scores on the self-rating depression scale than the placebo group. This scale is commonly used to screen adults for depressive disorders and is widely used in clinical research. Improvement in scores suggests L-theanine could be a great tool that helps people ease symptoms of depression.


L-Theanine May Boost Cognitive Performance

Today we are bombarded with information and interesting content from all sides. That makes it harder to concentrate on a task at hand. So, if you’re looking into alternatives to caffeine for focus, L-theanine is an excellent option, or at least science is starting to think so.


Results from a double-blind, placebo-controlled study indicated that consuming L-theanine with green tea extract helped improve attention and memory in people with mild cognitive impairment. These problems are common in older populations as, often, mental abilities being to decline with advanced age. In this study, researchers observed an increase in theta brainwaves in certain parts of the brain, which is a good indicator of mental alertness. In addition, subjects taking L-theanine and green tea extract performed better on memory tests.


2021 study exploring the relationship between caffeine, L-theanine and attention evaluated the cognitive performance of middle-aged and older adults after a single dose of L-theanine as well as after 12 weeks of supplementation. The results showed that the single-dose group presented improvements in attention, working memory, and cognitive functions. The results of this study also suggested that, while caffeine and L-theanine act synergistically in energy and wellness drinks, L-theanine might be the main player of the two with regard to these cognitive performance benefits.


Other studies examined how L-theanine combined with other chemical compounds to benefit cognitive performance. For example, combining it with epigallocatechin-3-gallate (EGCG) and caffeine (two important compounds found in green tea) improved people’s mood and helped them feel more alert.


Multiple studies demonstrated that combining L-theanine with caffeine positively affected alertness, energy levels, and the ability to focus on complex tasks. It appears that this combo is excellent for mentally demanding challenges, as it can help people improve speed, accuracy, memory, and the ability to ignore distractions. That’s why green tea is among the most popular mental-focus drinks.


What’s interesting is that L-theanine seems to cancel the stimulant effects of caffeine, which could reduce the negative side effects of frequent consumption of caffeinated beverages like coffee. An alternative to coffee that keeps you awake, alert and focused without the jitters and that weird clammy-hands thing? Yes, please!


It’s Possible that L-Theanine can Improve Sleep Quality

How often have you tossed and turned in your bed for hours, unable to fall asleep while your mind was running all over the place? That’s because stress and anxiety are natural enemies of sleep. And since clinical research indicates L-theanine may help reduce the effects of stress and anxiety, it is one of the best nootropics for sleep.


One study on the effects of a 4-week course of L-theanine consumption on sleep quality showed that subjects who took the L-theanine supplements needed less time to fall asleep, woke up less frequently during the night, and didn’t feel the need to take sleep-aid medication as often. This study specifically noted, as many others do, that the L-theanine was well-tolerated across the subject population, further supporting the claims that this nootropic is just as safe as it is effective.


In addition, supplementation with L-theanine may help improve sleep quality in people with schizophrenia and attention deficit hyperactivity disorder (ADHD). It appears that L-theanine helps balance levels of glutamate and glutamine in the brain, and disruptions of these neurotransmitters have been connected with the pathophysiology of these conditions.


Other studies confirmed L-theanine’s potential to improve sleep quality. This natural sleep aid could be one of the best nootropics for sleep because it doesn’t sedate or make you drowsy. Instead, it helps you relax on a biological level, making it easier to fall asleep, and improving the quality of your sleep.


Research Suggests L-Theanine Supports Your Immune System

Tea consumption is considered to have beneficial effects on your immunity. Catechins, powerful antioxidants in green tea, are the main compounds responsible for these effects. However, one study indicated L-theanine could help to improve lymphocyte function in the upper respiratory tract, increase antibody response, and reduce markers of inflammation.


This nootropic also has anti-oxidative properties, which are thought to help immunoregulation. A normalized immune system has beneficial effects on most organs in our body.


In addition, L-theanine may aid athletes in recovering faster after intensive workout sessions by modulating specific inflammation markers. Quick recovery is vital for better performance, so this improvement can be a great advantage for elite athletes. These physical benefits are why you’ll often find L-theanine in energy supplements, especially powder mixes for pre-workouts or morning wake-ups.


Overall Indications Suggest L-Theanine May Improve Mood

This one’s a bit of a cherry-on-top benefit of including a nootropic tonic in your daily routine: If L-theanine drinks and supplements can help promote reduced anxiety, stress and depression, and all of these have significant effects on your mood, it would follow that L-theanine may aid in mood regulation and perceived mood levels. For example, results from one study suggested taking L-theanine could reduce headaches and mental fatigue while promoting better mood and alertness.


So, if you’re searching for the best nootropics for mood support, L-theanine should definitely up there on your list.


How Does L-Theanine Work?

When you consume an L-theanine drink, this molecule quickly enters your bloodstream and begins to interact with important brain chemicals and neurotransmitters. Studies show that L-theanine needs around 30 minutes for the effects to kick in.


In the brain, this nootropic interacts with different receptors, affecting the levels of many neurotransmitters. That includes: 


  • Norepinephrine: involved in attention, focus, mood
  • Serotonin: involved in mood, memory, learning
  • Tryptophan: involved in sleep, energy, cognitive function
  • Glutamine: involved in energy, immunity, digestion
  • Glutamate: involved in movement, learning, memory
  • Gamma-aminobutyric acid (GABA): involved in anxiety, brain function, muscle relaxation
  • Dopamine: involved in motivation, movement, mood


The levels and interactions between these neurotransmitters are vital for regulating mood, anxiety, satisfaction, and other aspects of our mental well-being. If L-theanine acts to balance their levels, our nootropic achieves its health benefits. While many nootropic compounds have targeted benefits, L-theanine’s wide-ranging effects on our CNS makes it a multi-faceted nootropic, which is why the health and wellness industry is so fond of this jack of all trades.


Is L-Theanine Safe?

L-theanine is generally recognized as safe by the FDA. This is backed by many studies where people took this amino acid supplement for 8-10 weeks without observable adverse side effects.


Some people report brain fog and headaches after taking L-theanine. Others have experienced nausea or irritability. However, these side effects are mostly linked to unusually-high doses.


We need more evidence to confirm the safety of L-theanine for certain groups of people. If you have any of the following conditions, it’s important to discuss adding a feel-good energy powder with L-theanine and other bioactive plants to your daily routine beforehand: 


  • People who are pregnant or breastfeeding
  • People with low blood pressure
  • People taking blood pressure-lowering medications
  • People taking stimulants for mental health disorders


Should You Take L-Theanine With Other Supplements?

L-theanine is often a part of stress relief and mental focus powder mixes and tonics because of its spectrum of versatile benefits. Clinical research and real-life application suggest L-theanine acts synergistically with a number of other bioactive plants, including adaptogens and superfoods. So, yeah - it combines great with other supplements. That’s why we’ve included it in the unique formulation of our More Than Energy (MTE) daily wellness powder.


MTE is a natural feel-good drink mix that promotes your energy levels and aims to help you deal with stress and anxiety. It combines L-theanine with 11 adaptogens, nootropics, and superfoods, giving you all the support you need to be your best self every day.


Drinking a daily dose of MTE may help boost energy levels, alertness, stress resilience, anxiety management, mood, calm focus, and so much more. We recommend mixing one scoop of MTE’s clean energy mix into water, your favorite smoothie, or to augment another daily green drink. Take it in the morning to wake yourself up, or in the afternoon to boost you through the rest of your day.


This unique energy supplement powder uses some of the most potent natural ingredients to achieve amazing things. It is formulated for a sustainable energy boost that doesn’t leave you crashing afterward. More importantly, it has the potential to mitigate the effects of stress and reduce anxiety levels, making this natural energy supplement a perfect stress relief drink.


Drinking MTE before a big exam, work presentation, or another stressful event could help you remain focused and tune out bad thoughts and distractions.


Order MTE to discover how this wellness-focused mix of greens can help you improve mood, reduce anxiety, manage stress, improve sleep, boost energy, and more.

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