What is L-Theanine?

What is L-Theanine?

All about this essential amino acid, an important nootropic.

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If you’ve ever felt overwhelming, exhausting stress, chances are you’ve already started to look into your options. There’s regular exercise,  changes in diet, and daily meditation, but if you’ve started to look into supplements, chances are you’ve already come across L-Theanine. This amino acid seems to be everywhere these days, but not a lot of information is out there about what it actually is. Here’s a guide to help you understand what it is, where it comes from, and how it impacts your brain –– specifically, how it can work to help improve memory and focus.

What is L-Theanine?

L-Theanine is technically an amino acid, although not a protein, (which are made up of amino acids), and is not naturally produced by the body. It bears a close resemblance to glutamate, another amino acid, although has the complete opposite effect.  Glutamate is the most abundant amino acid in our diet and functions as an excitatory neurotransmitter, but specifically, it is directly responsible for many of our body’s internal stress responses.  L-Theanine is able to bind to the same receptors as glutamate, only because it functions as an inhibitor, L-Theanine is able to suppress those same stress responses –– leading to decreased feelings of stress. 

Where does it come from?

L-Theanine is found naturally in green tea leaves, specifically Camellia sinensis. Though this plant has been traditionally used in Chinese medicine for thousands of years, it was identified by scientists in 1949. However, drinking a cup of tea will not provide you with the same amount of L-Theanine as you would get in a standalone supplement (approximately 20mg), and therefore would not provide you with the same benefits.

It also has been known to trigger taste buds that are associated with umami, or the “5th taste” and has the ability to “improve the taste of processed foods and beverages” by acting as a signal for proteins to then communicate directly to the brain of the available of important nutrients. In matcha tea specifically, L-Theanine is thought to the compound that provides the tea with its slightly sweet notes.


While it does help to reduce stress due to its ability to inhibit glutamate, the full extent of  L-Theanine’s benefits are just beginning to be discovered. Here are some of the other ways in which it works:

Improves mental clarity and relaxation, and boosts focus

When we’re unable to focus, chances are there are external factors (noisy neighbors, distracting environment), but the reality is that many of the reasons why we have trouble focusing actually live inside of our own head; specifically, in our brain. There are five different types of brain waves –– Alpha, Beta, Gamma, Theta, Delta, and Infra-Low ––  that are directly responsible for how our neurons communicate with each other, creating the basis for our emotions and thoughts.

Brain waves change depending on how we are feeling and what we are doing, and each have their own speeds and frequencies. We feel tired, slow, and dreamy when the slower brain waves are dominant, whereas when the higher frequencies are dominant, we feel alert and wired. In order of slowest to fastest, the brain waves can be organized as such: Infra-Low, Delta, Theta, Alpha, Beta, and Gamma. Infra-low brain waves are the slowest, with Gamma being the fastest. In terms of L-Theanine, however, the two important ones to focus on here are Alpha and Beta.

Beta waves are the most common ones during a conscious, awake state, and in general are the ones that help us focus on the task at hand. However when our beta levels are too high, we can swing into anxiety, feeling stressed out and unable to feel relaxed. This is where Alpha brain waves come in. Alpha brain waves are associated with feelings of creativity, relaxation, and rest, and aid overall mental coordination, alertness, mind/body integration and learning.

Studies have found that  L-Theanine helps to stimulate Alpha Waves in the brain while also decreasing the Beta waves –– creating an ideal focused mindset. In an additional study, those who paired L-Theanine with caffeine found was able to improve cognition and overall alertness –– making it a great option for those looking for focus tips.

Increases production of GABA and serotonin levels 

GABA, or gamma-aminobutyric acid, is an important amino acid that functions as a neurotransmitter, helping to provide a calming effect. Recent L-Theanine studies have shown a direct correlation between L-Theanine and increased GABA levels, meaning that continued supplementation could further help feelings of anxiety and stress.

Serotonin is an important hormone that acts as both a neurotransmitter, and a vasoconstrictor, or a substance that causes blood vessels to narrow. It stabilizes our mood and feelings of happiness, and an imbalance of it can lead to depression and excessive nerve cell activity.  L-Theanine has been studied for its ability to elevate serotonin levels as well, which can further help to regulate emotions, concentration, alertness, and sleep.

Heart helper: boosts nitric oxide production

Nitric oxide is essential for our bodies to function. It functions as a transmitter, and plays a particularly important role in our cardiovascular health. Nitric oxide  relaxes narrowed blood vessels, which then increases blood flow and oxygen in the heart. The endothelium, or the interior surface of your arteries, are able to produce nitric oxide, which is reduced when plaque builds up in them. Since nitric oxide helps blood through through our arteries properly, it helps to reduce the risk of a stroke, and has even been suggested by scholars that supplementing with L-Theanine directly after a stroke can help to reduce the damage and severity.

Improves sleep quality

A racing mind can often be a barrier between you and a restorative night’s sleep. Because of L-Theanine’s ability to boost GABA, serotonin, and dopamine levels, this helps your mind settle down, so you can relax and gently drift off. Due to its ability to enhance Alpha waves as well, which are directly associated with a calm and relaxed mind. So when anxiety and stress levels are managed by L-Theanine, you’re able to get a restful night’s sleep.

L-Theanine vs. Suntheanine

While L-Theanine is the name of the amino acid, Suntheanine is a patented version of the ingredient that was engineered to provide maximum efficacy. It’s clinically studied and is generally considered to be the superior option due to the fact that it is more concentrated and therefore able to be taken in smaller doses, and is overall purer in terms of quality. It is important to note, however, that Suntheanine is not a green tea extract, but rather, is produced via a process that mimics the natural process in green tea leaves.  

How we use it

Instead of creating a single L-Theanine supplement, we wanted to design a cognitive supplement that took care of focus and mental clarity immediately, but also provided users with long-term cognitive support. This led to NOOTRO-FOCUS, our first cognitive supplement that, in addition to L-Theanine, incorporates other nootropics and adaptogens such as Rhodiola, Bacopa, Citicoline, and Lion’s Mane Mushroom. It provides you with the same benefits from a standalone L-Theanine pill, but with additional support, ensuring that your brain and mental health are covered from all angles. Suntheanine, the version of L-Theanine that we use in Nootro-Focus is isometrically pure, made from amino acids ethylamine and L-glutamine and created by using a proprietary enzymatic process that directly imitates the natural green tea leaf process.

But wait –– what are nootropics and adaptogens? 


Nootropics (pronounced new-troh-picks) are supplements that are designed to function as brain boosters, commonly referred to as “smart drugs” because of this. The term comes from Greek, meaning “to bend or shape the mind,” and was originally coined by Dr. Corneliu Giurgea, a Romanian chemist and psychologist, when he was attempting to invent a sleeping pill but instead created piracetam, which he then called a nootropic.

According to Dr. Giurgea, there are a few requirements for what constitutes a nootropic. The proposed substance needs to:

  • Enhance memory
  • Improve behavior under adverse conditions
  • Shield the brain from injury through either chemical or physical means
  • Improve tonic cortical/subcortical control mechanisms
  • Demonstrate a low toxicity and side-effect profile

Though this is a relatively new term, certain plants have been used traditionally in medicine for thousands of years to improve mood and cognition, causing them to be defined as nootropics only recently in history. You may be already with some of these natural, plant-sourced ones such as Ginkgo and Bacopa, as well as recent pharmaceuticals Ritalin and Adderall, which are also considered to be nootropics due to their ability to strengthen concentration.

L-Theanine is classified as a nootropic as well, due to its ability to impact neurotransmitters, cognition, and brain waves, among other benefits.


Where nootropics are specifically designed to target performance and overall cognition, adaptogens work to help balance your hormone levels, in an attempt to help your body adapt to stress. They are plants and herbs that work to stabilize the endocrine and autonomic nervous systems.

Many adaptogens could technically be classified as nootropics due to their makeup and benefits, which often leads to a confusion between the two, or for the two terms being used interchangeably. However, it’s important that the two terms remain distinguished, as at the end of the day, they have separate goals: adaptogens work primarily on stress, whereas stress reduction is just one of many goals for a nootropic.

If they have overlapping goals, can I take them together?

Since there are so many different types of nootropics and adaptogens, it’s not as easy as saying “yes, you can take any of them together,” but rather it is important to note that there are certain combinations of adaptogens and nootropics that work symbiotically. The blend of adaptogens and nootropics in our Nootro-Focus were individually selected due to their ability to work together in taking on a plethora of goals, but specifically, with the intention of creating a supplement that offered both instant results as well as long-term ones. In general, if you’re on the fence about which nootropics and adaptogens you should take, starting with a supplement like Nootro-Focus that has a pre-selected combination of the two is a smart way to go, as its ingredients have been clinically proven to support mental energy, focus, and attention. You can also speak with your doctor or pharmacist for any additional recommendations, especially if you are currently taking additional medication, to avoid any negative effects from the nootropic.

What people had to say about our nootropic, Nootro-Focus

Customer testimonials:

“A month ago, I got invited to an onsite interview at one of the largest tech companies. I knew I had to try Nootro-Focus before my interview. Right before getting into the building, I realized I had no water with me. I took two pills from my bag and just swallowed without any water. The interviews were a blast, first I did an amazing presentation to the whole team and then killed every single interview after it. And I received the job offer at my dream company last week!” -YG

“On the 3rd day of taking this alone, it was like my speech patterns were switched on auto pilot. I find it to work best (for me) when taken on an empty stomach, plus I take a natural peach tea energy shot which I find it to be the best combination I have ever come across. My focus has gotten better and honestly I don’t want to overhype it for anyone but this stuff is really good.” -Alan

“I started using this product during a super hectic time at work. It has kept me from reaching for that second (or third) cup of coffee throughout my work day. I am able to focus on my big tasks, and when I get torn away and need to help a colleague, I am still able to offer my assistance and get back on track. I've also been feeling like I still have some brain power left after work to dedicate to my personal projects. Highly recommend!” - Taylor R.


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