Best L-Theanine Supplements

Class of Compound


Mechanism of Action

L-Theanine is an amino acid that is found in green tea. It is supposed to work by increasing the levels of dopamine in the brain that improves mood.

Street Names



  • Improves cognition and mood
  • Improves sleep quality
  • Helps relieve stress and anxiety

Side Effects and Dangers

  • Increases irritability
  • Stomach upset
  • Nausea

Chemical Structure

Sometimes, you just want to feel relaxed, not sleepy or sedated, sadly most supplements capable of inducing relaxation are also capable of making you feel sleepy, in other words; they equally act as sedatives. They don’t offer one without the other.

This is where L-theanine supplements come into play. It’s arguably the only supplement that is capable of making you feel relaxed, without putting you to sleep. If this sounds like something you’re looking for; then let’s delve into the subject of theanine for the proper understanding of the supplement and how it works.

In reviewing the top 5 L-theanine supplements; some of the criteria considered include brand, digestibility, taste, percentage yield per serving, vegan-friendly, supporting components, as well as the price. After the top five you can read more about L-theanine, Dosage, and best practices.

Best Pure: L-Theanine by Bulk Supplements

Best L-Theanine Supplements L-Theanine by Bulk Supplements offers wide-ranging health benefits which include better sleep, enhanced cognitive function, improved heart health, and greater immunity.  This product contains 250 milligrams of L-Theanine per serving and is free of additional ingredients or additives such as sugar, soy, dairy, yeast, gluten, and corn. L-Theanine is available in pure powder form as well as in vegetarian or gelatin capsules. The powder form of this product is available in quantities ranging from 50 grams to 25 kilograms whereas both forms of gelatin capsules are available in quantities of 100 or 300 capsules. This product should be taken by adults one to three times daily at a serving size of 100 mg to 250 mg.

BulkSupplements offers over 500 supplements which fall under categories such as fitness and sports, heart health, brain and memory, weight management, and immune support. All of its products contain pure raw ingredients, are lab tested for purity, and are manufactured at a facility that is FDA inspected. BulkSupplements stands out among its competitors due to its product versatility and ability to serve customers who stem from diverse health backgrounds, lifestyle choices, and dietary preferences.

  • Free of additives No other ingredients Wide range of health benefits
  • Some people may want additional ingredients Some people may require higher dosage

Disclaimer: The content on and the information included in this article is intended for entertainment and informational purposes only. It is not intended nor implied to be a substitute for professional medical advice. Prior to buying anything, check that it is compliant where you live with your current government laws. Your access is subject to our full Terms of Use.

Best Blend: Mind Lab Pro

Mind Lab Pro Review

Price: $65 for 60 capsules Mind Lab Pro® is the cleanest nootropic ever developed. A 100% natural, vegan and stim-free whole-brain optimizer that supports daily mental performance and healthy long-range function. Formulated to promote a healthy, peak-performing mindstate known as 100% Brainpower™.

best nootropics review

Features: Mind Lab Pro® is the world’s first Universal Nootropic™. Stacking 11 research-backed ingredients in range dosages. To support full spectrum cognitive function for all types of people. From athletes to entrepreneurs to older adults.

Optimizing mental performance in four key categories: Memory – for recall, learning and test-performance. Performance – for focus, alertness and speed of thought. Mindset – for calm, creativity, motivation and mood. Structural – for repair, restore and neural regeneration. Ingredients Mind Lab Pro® sources premium quality ingredients, in advanced forms. Branded and patented, standardized and calibrated for maximum potency. Featuring Suntheanine® L-Theanine (100 mg), Citicoline (250 mg) as Cognizin®, Phosphatidylserine PS (100 mg) as Sharp PS® Green, L-Tyrosine (175 mg) as N-Acetyl-L-Tyrosine (NALT). Plus, Bacopa Monnieri (150 mg), organic Lion’s Mane Mushroom (500 mg) and B6, B9 and B12-vitamins.

  • High Purity

  • Stimulant-Free

  • Fully Transparent

  • Only Available on Company Website

Qualia Mind by Neurohacker Collective

Best L-Theanine Supplements

Qualia Mind by Neurohacker was carefully developed by top scientists to enhance cognition through the use of natural, extremely potent ingredients. This product is best known for improving energy duration, providing mental clarity and enhanced cognition, and amplifying willpower while decreasing procrastination. 

Not only does Qualia Mind exhibit immediate effects, but it also enhances long-term cognitive health through supporting neuron and synapse development and increasing mitochondrial ATP. 

Some of the major ingredients found in this product include L-Theanine, Huperzine A, Coffeeberry® (caffeine), Pyrroloquinoline Quinone (PQQ) and Cognizin® Citicoline. Adults should take 7 capsules daily for up to 5 days.

  • Vegan-Friendly

  • Both caffeine and caffeine-free versions available

  • Non-GMO

  • Needs to be cycled

  • 7 capsules at once

  • Can only be used 5 days a week

15% OFF WITH CODE: Nchip

How L-Theanine Works

L-theanine is an amino acid first discovered by Japanese scientists in green tea in 1949, although it’s lately been discovered that humans have been benefiting from this fascinating substance for centuries. It is an analog of glutamate and with plenty of benefits.

It’s also capable of modulating and increasing alpha brain waves being a form of L-glutamic acid. Alpha brain waves are electric impulses which produce feeling of calmness and relaxed alertness. Higher presence of these waves helps to control the over-activity of beta waves. Larger presence of beta waves creates a sense of fear and anxiety. Because of its ability to keep beta waves in check, it’s often supplemented for general anxiety disorders, social anxiety, and depression.

Another way L-theanine helps to fight off anxiety is by increasing the secretion of joy hormone known as dopamine. Increase of dopamine in the brain automatically improves the mood.

Other neurotransmitters such as serotonin, norepinephrine, and GABA are also targeted by this substance, all of which are responsible for treating anxiety. These neurotransmitters regulate different actions of the sympathetic nervous system, such as the “fight or flight” response. A sense of calmness is achieved as an inhibitory effect of this substance on the mind.

The effects on different neurotransmitters also help with other cognitive processes such as sleep and relaxation cycles, pleasure, and the brain’s reward system.

L-theanine has a unique ability to cross the blood-brain barrier, which allows it to be absorbed into the bloodstream faster, causing the substance to show results faster. This allows all effects of L-theanine to be seen at a faster rate. One huge benefit of L-theanine being able to break the blood-brain barrier is found when paired with GABA.

L-Theanine and GABA

GABA is one of the amino acids that is found to occur naturally in the body. This amino acid works to keep neurons in the brain from over-working. GABA also has other purposes, like boosting muscle growth, but its main function is to work as a neural calming agent. It is classified as an anxiolytic, which is the term given to any supplements that is capable of reducing anxiety symptoms. GABA supplements have also been created by scientists in an attempt to fight anxiety symptoms. However, there is one small problem. When GABA is taken orally as a supplement, it fails to cross the blood-brain barrier, thus limiting its effects compared to natural GABA.

But, L-theanine and GABA can work harmoniously. We have already discussed that L-theanine is psychoactive, which means it can break the blood-brain barrier and be absorbed in the bloodstream fast. GABA can then do its job, and the L-theanine also stimulates GABA production. This is one of the major reasons why L-theanine is so effective in fighting off anxiety and depression.

What is the Right Dosage of L-Theanine?

While L-theanine is really helpful in treating anxiety, taking this supplement in the right amount is extremely important. The dosage isn’t the same for everyone. Various factors like body weight, sensitivity, symptoms of anxiety, etc., are the factors that matter when determining the right anti-anxiety dose of L-theanine.

You will want to start with a small dose of somewhere around 50 mg to 100 mg. This is the same dosage used in the supplement Cognishield. The effects of L-theanine are generally felt somewhere around the 60-minute mark. Don’t jump through the dosage amount too quickly. You must properly assess your physique and your health status in order to decide just how much L-theanine your body requires. Regularity of this supplement is the key to maintaining proper brain health. So, your best bet is to take low doses, but at a regular time interval for maximum effects. Doing so will equip your brain with the right neurochemicals and your neurotransmitters will be stimulated regularly. Taking this supplement in a proper way means you don’t have to worry about the risk of side effects, also you can avoid having to spend your hard-earned money on prescribed medications.

User Reviews

While L-theanine has been proven to be highly effective for anxiety, users have expressed different opinions on what the effects of this supplement are. Many users have expressed that taking higher doses of L-theanine, around 400mg produces a more relaxing effect, and can even encourage feelings of sleepiness and fatigue. However, it’s not to say that lower doses aren’t effective, in fact, there are plenty of users who are happy enough taking lower doses. Those who take higher doses for extra relaxation also agree that even lower doses help them to concentrate better and for longer hours without the feelings of panic and nervousness. It can be stacked with either Phenylpiracetam or Noopept to help bring a feeling of calmness to balance the intensity of these nootropics.

What is L-Theanine?

L-theanine or Theanine is an amino acid, present only in green tea. A larger percentage of the amino acid needed by the body to function effectively are either produced in the body system or readily available in our diet. This isn’t the case for L-theanine. It’s a very rare amino acid found only in tea leaves and some fungal species. What this implies is that; if you want to enjoy the benefits that the amino acid offers; then you have to source for it through supplements. The aim of this article is to discuss in details what L-theanine supplement does and also offer a good recommendation on the best L-theanine supplements in the market. L-theanine has an enantiomer, the D-theanine.

Very few research work has been done to examine the effectiveness of the D-theanine since the most prevalent type is the L-theanine. Even though D-theanine is less discussed, it’s been shown that they are usually present in most theanine supplements; albeit in minute proportion. One of the unique characteristics of L-theanine is its ability to cross the blood-brain barrier; which is like a filter that prevents the absorption of materials into the brain cells.  The structure of L-theanine is very similar to a neurotransmitter called glutamate. Glutamate is an excitatory neurotransmitter. The ability of L-theanine to cross the blood-brain barrier makes it an antagonist on glutamate receptor. It also increases the level of serotonin; an inhibitory neurotransmitter. This results in various psychoactive effects, which will be discussed in details in later part of this guide.

Benefits Of L-Theanine Supplements

Fix For Stress and Anxiety: The major reasons why people take L-theanine is to calm their nerve against anxiety. If you’re prone to anxiety, then you would want to take less of caffeinated drink and opt for theanine. The supplement is capable of interacting directly with the brain cells to reduce the presence of glutamate which is an excitatory neurotransmitter.

Improve Cognition and boost mood: L-theanine has been associated with the increase in alpha brain wave during the scan. Research has also shown that alpha brainwave is associated with increased creativity and reduces depression.

Inhibit Glutamate Excitocity: Accumulation of glutamate in the cell usually result in excitotoxicity due to the excessive stimulatory action of the neurotransmitter. Since L-theanine is similar in structure with glutamate, then it shares it’s receptor by binding with them as an antagonist, thereby reducing the overall impact of the neurotransmitter on the cell.

Improve sleep quality in people with ADHD: Although not a sedative, the supplement has been reported to improve quality of sleep by getting rid of anxiety and making user calm; especially in those with ADHD.

Improve learning and memory: It’s been reported to have a direct impact on the learning and memory of users. This is explainable based on its ability to cross the blood-brain barrier and act as a psychoactive. There are other benefits such as treatment of stomach cancer, asthma etc, but the effect is not well documented in these cases and the further test must be conducted before it becomes an ascertained fact.

What is the Right Dosage OF L-Theanine

Drug or supplement dosage depends on a wide range of several factors, from body weight to tolerance, as well as age. However, based on general consensus, from frequent users; it’s been reported that 200mg is the average dose required to elicit the desired effect.

This explains why taking green tea does not give the desired result. Because a typical cup of green tea contains just about 25mg of L-theanine, to get the desired result that supplement will give, about 8 to 10 cups of green tea must be consumed to attain the average dosage. It’s important to take note that tea does not just contain L-theanine, it has other ingredients as well, such as caffeine


There have been reports that taking this supplement alongside caffeine gives a whole new level of experience. It’s important to understand your body system before you load up on dietary supplements generally. Ask questions when you’re not clean about the ingredient of a particular product and go the extra mile getting the answer before taking the supplement.

Dr. Dimitar Marinov

Dr. D. Marinov is our medical expert. He has written, fact-checked and medically reviewed tons of articles on topics about medicine, health, infections, and nutrition.

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1 Response

  1. Very good article, easy to understand.
    However, there are a number of grammatical errors and misspellings. Correcting these would enhance the professionalism & credibility of the info.

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