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L-Theanine Powder

Goes Well With

One of the major problems people have these days is stress. Stress from traffic, stress from work, and stress from home. Stress clouds our thinking, and stress makes us unhappy.

There is a naturally occurring amino acid, L-Theanine, which has shown to not only reduce stress but also promote lifespan, health, and focus. By supplementing with L-Theanine, you just might find yourself relaxing and taking on life in calm, alert, and productive way.

What is L-Theanine Powder?

L-Theanine is an amino acid found most commonly in green tea (Camellia sinensis).[1] [2] It is a form of L-Glutamic acid and can increase alpha waves in the brain.[2] Alpha waves promote a feeling of relaxed alertness.[2] It is considered safe and is well-tolerated in humans.[1]

L-Theanine Benefits and Side Effects

L-Theanine is a popular supplement for many purposes. The vast array of advantageous Theanine side effects include its ability to benefit cognitive and mental states, help counteract beta-amyloid formation, possibly improve body mass, and support healthy blood pressure.[1] Scientific studies of L-Theanine have concluded that it can provide immune system benefits.[2]

Some evidence suggests that through its stress fighting mechanisms, L-Theanine could help improve the quality and length of life.[1]

L-Theanine can support recovery from the high-activity mental state caused by rigorous exercise.[3] It does this by bringing brain waves back to normal levels quickly and helps promote mental regeneration.[3]

When used in combination with caffeine, L-Theanine can help reduce the increase in blood pressure that results from the stimulation of caffeine.[4] L-Theanine can also eliminate the jittery, over-wired feeling caffeine can sometimes cause, and, on top of that, L-Theanine synergistically increases the cognitive benefit of caffeine.[4, 5] For this reason, many often combine L-Theaine and caffeine to create a potent and popular nootropic stack.

L-Theanine has shown to have effects on serotonin, dopamine, GABA, and other neurotransmitters including norepinephrine.[2] Its increases of GABA in the brain help lower activity in the adrenaline systems, another pathway for L-Theanine to promote a sense of calm.[2]

L-Theanine Dosage

L-Theanine is present in many varieties of tea, but almost always occurs in too small a dose to be effective. For this reason, L-Theanine supplementation is crucial to derive the most benefit from this natural compound.

L-Theanine can be active with as little as 50 mg, but 100 mg is a more common dose.[3] When combining with caffeine for the synergistic mental boost, a ration of two parts Theanine supplement for one part caffeine is typical.

Check out our Theanine Serene with Relora Capsules!


  1. L-Theanine extends lifespan of adult Caenorhabditis elegans
  2. Eschenauer, Gregory, and Burgunda V. Sweet. "Pharmacology And Therapeutic Uses Of Theanine." American Journal of Health-System Pharmacy 63.1 (2006): 26. Academic Search Elite. Web. 12 Sept. 2012
  3. Improving mental regeneration after physical exercise
  4. Herbal Extracts and Phytochemicals: Plant Secondary Metabolites and the Enhancement of Human Brain Function

Additional Resources

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L-Theanine Powder Reviews
4.8 out of 5, based on 4 reviews
Sebastian from Poland on Sep 15, 2014
Makes me very productive along with with coffee, alone visibly decreases anxiety.
John from Florida on Sep 12, 2014
Awesome stuff. I make a cap first thing in the morning so it's in my system before I make my coffee. It takes a lot of the edge off of the days I need take Phenylracetam.

I would recommend is getting a jar for this powder. It's like flour, so you are going to have powdered covered hands every time you reach in the bag to take a scoop.
Justin DiMuccio from Waxhaw, NC on Sep 09, 2014
I ordered this for the use of anxiety reduction as well as a sleep aid. Being prescribed to benzos, the anxiety reducing effect was very minimal. It was however, noticeable. TRY THIS BEFORE A BENZO! Please don't trap yourself like I did. Anyway, at 400+mg with melatonin, this stuff gives me a great sleep. I wake up feeling refreshed!
Stacy from Mississippi on Sep 03, 2014
This is another go-to for anxiety. Almost as effective as xanax. Combined with melatonin and inositol, it makes an excellent sleep mixture.


Statements found within have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease. Always consult a physician if you are unsure about taking a new supplement or nootropic. Do not take this product if you are under 18, if you are pregnant, nursing, or have any cardiovascular issues.

Scientific studies cited are not conclusive and have limitations, due to of their closed environment nature. Referenced studies will not necessarily determine your experience with a supplement or nootropic, since there are many unaccounted variables, which fall outside the scope of the studies.

The reviews contained within are the opinions of contributors and are not necessarily the views or opinions of Powder City. These reviews should not be taken as fact or recommendation, and are only opinions of products that the contributors may have or may have not used. Powder City makes no warranty, implied or expressed, to the accuracy of information provided by these reviews.