L-Theanine is one of the most ubiquitous nootropics that few people are aware they ingest. As a main psychoactive constituent of tea leaves, this amino acid has been improving brain health for thousands of years across the globe. Despite deriving this from natural means, how useful is L-theanine really?

According to studies in the past few decades, this specific nonessential amino acid is one of the most useful tools for people using smart drugs. The primary effect and benefit of L-theanine is helping improve upon the positive aspects of caffeine while mitigating the negative aspects (such as anxiety, increased blood pressure, and diminished sleep quality) [1].

Beyond these benefits L-theanine alone can be a powerful nootropic often heralded as a relaxation enhancing tool similar to meditation. The compound improves alpha brain waves, which is a pattern in the brain correlated with the highest activity and mental capacity [2].

For beginners to nootropics, L-theanine may be one of the safest nootropic options that you can find. In the United States it has “Generally Regarded As Safe” (GRAS) status and dozens of studies prove efficacy and safety even at high doses [3].

Also Known As

Theanine, 5-N-Ethyl-Glutamine, Suntheanine (Brand name)

Editors’ Thoughts on L-Theanine

I don’t actually “feel” much of L-theanine when I take it by itself, but perhaps that is the point. Unlike stimulants, it helps to calm the nervous system and I suppose it has helped even if I did not notice it.

The best experiences I’ve had with L-theanine include caffeine as well, which is definitely noticeable. I actually rarely have caffeine without the pairing of L-theanine because it is so effective at preventing the anxiety and jittery nature of the stimulant beast.

I’d suggest L-theanine is probably one of the best bets for someone who is on the fence about starting nootropics. You’ll find this to be a simple way of getting started and effective as most people use caffeine in some form or another.

Mansal Denton, Nootropedia Editor



History of Theanine

The actual molecule of theanine was discovered only in 1949 and separated from leaves in order to supplement. However, theanine has been used for far longer than that. The records suggest people in China have been using tea leaves for thousands of years.

As legend goes, a Chinese emperor was boiling water when tea leaves fell into his water and he drank the concoction. Whatever the true origins of tea consumption, the effects they had on sensitive ancestors of ours made them staple crops and highly popularized.

Today, tea is still highly consumed around the world and specifically for the medicinal benefits. The relaxing and calming nature of tea comes primarily from the theanine content in the leaves and brew. The only drawback of L-theanine from tea is the quantity and dosage is very low. This is one of the main reasons for the growth in L-theanine supplements.

Benefits of L-Theanine

There are a whole host of benefits of L-theanine that users experience simply drinking tea or taking a higher dose of the extracted and supplemented form. For one, L-theanine is an anxiety reducer, which can consistently support people suffering from mental tension [4]. One study showed that, while not as powerful as prescription drugs like Xanax, L-theanine was able to promote relaxation and calmness [5].

Another benefit of L-theanine is a notable increase in feelings of relaxation and calmness without the feeling of sedation (which can make one lethargic) [6]. There is one study that focuses on how theanine improves relaxation via alpha waves in the frontal and occipital lobes within 30 minutes of consuming the supplement.

Of course, a downstream effect of improving feelings of anxiety and relaxation is improved sleep quality. Even though the sleep duration and latency are not affected by theanine, one study on children showed sleep quality was far higher when taking this supplement [7].

One of the unique L-theanine benefits is how it can improve attention and focus despite the relaxation response. If this seems contradictory, argue the point with science which has repeatedly showed theanine’s ability to enhance attention independent [8] and in a combination of caffeine [9]. This improvement in focus is often why people turn to nootropics and makes it simple for a new person to get started with a simple and natural nootropic like L-theanine.

Finally, as if theanine wasn’t already useful enough, the supplement can also increase a chemical called brain derived neurotrophic factor (BDNF) by up to 25% and NGF by 100% in regions where memories are formed (the hippocampus) [10].

L-Theanine and ADHD in Children

Given that there are so many children in the United States (and other western countries) who are being given medications for attention deficit disorder (ADD / ADHD), it is worthwhile to look at alternatives. Most of the prescription drugs are made with amphetamine salts that have long-term effects on children that are not beneficial.

Children who often suffer from ADHD often have poor sleep quality and theanine is a great remedy. One study showed children using theanine did not sleep any longer, but had far better quality [11], which significantly alters their ability to focus during waking hours.

While more evidence is needed on the subject (especially supplementation during the day), it is clear that L-theanine can be a great supplement for ADHD and an Adderall alternative for your children.

Side Effects of L-Theanine

From a safety perspective, there are few drugs you need to worry about less than L-theanine. There are relatively few side effects of L-theanine and only anecdotally do we see headaches by dosing this nootropic. In many of the studies on extreme doses, there is no adverse or toxic effects. In fact, one study showed no adverse effects at 6500 mg / kg of bodyweight, which is 4225 grams of L-theanine in a single day [12].

Unlike some of the other more potent drugs, you don’t really need to concern yourself much with L-theanine side effects. In general, they are mild and do not effect many people.

L-Theanine Dosage

The L-theanine dosage will depend on your own personal biochemistry, but most sources suggest a range of 200 mg per day at one time. This dosage is usually paired with caffeine so your 200 mg dosage might be best in the morning.

There is a lot of evidence to suggest a ratio of 2:1 L-theanine to caffeine is perfect for the cognitive enhancing and synergistic properties of both substances. Usually, there is around 100 mg of caffeine in a cup of coffee so pairing with a theanine supplement can probably do the trick.

How and Where to Buy L-Theanine

Theanine is generally regarded as safe (GRAS), which means it has a regulated status in the United States that makes it almost ubiquitous. You can find it in your local grocery store, supplement shop, or there are plenty of retailers online.

One of the main advantages if you buy L-theanine online is that you will have access to price check all of the different options available to you. Even though this might not be something that seems like a good use of your time, researching your L-theanine purchase might teach you a thing or two that you didn’t know.

Vendors like Pure Nootropics are not only offering safe L-theanine for sale, but they also have sublingual solutions to help with administration. Some people like this administration method because the psychoactive ingredients are not metabolized by the intestinal tract so it can enter the bloodstream faster and more effectively.

Selected Community Experiences

The bottle says to take it on an empty stomach, so I ate breakfast around 7:30, went to work, had a cup of coffee + shot of espresso around 9, then at 10 I took 150mg of l-theanine. Next thing I know it's 5:30 and I got a ton of work done. It seemed unreal, the day felt like an accordion smushed together. [13]- ep0

been taking it for over a week now, and it's awesome. I'm a coffee snob, but I was getting too jittery and stressed. With L-Theanine, I feel so much more relaxed, I don't carry as much stress in my shoulders/neck, and my coffee just makes me awake and focused now without feeling strung out. [14]- dgutty

References (Click to Expand)
  1. //www.ncbi.nlm.nih.gov/pubmed/16930802
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  11. //www.ncbi.nlm.nih.gov/pubmed/22214254
  12. //www.taiyointernational.com/Downloads/2007.rao.suntheanine.nutracos.pdf
  13. //www.reddit.com/r/Nootropics/comments/2162cd/omg_is_ltheanine_amazing/
  14. //www.reddit.com/r/Nootropics/comments/3ouv0y/adding_to_the_ltheanine_praise/
Other Scientific Resources (Click to Expand)
  1. //www.ncbi.nlm.nih.gov/pubmed/17904164
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  4. //www.ncbi.nlm.nih.gov/pubmed/18296328
  5. //www.sciencedirect.com/science/article/pii/S0924224499000448
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  10. //www.ncbi.nlm.nih.gov/pubmed/18997398
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  12. //www.taiyointernational.com/Downloads/2007.rao.suntheanine.nutracos.pdf
  13. //www.google.com/patents/WO2004016798A1?cl=en
  14. //www.ncbi.nlm.nih.gov/pubmed/16930802
  15. //www.ncbi.nlm.nih.gov/pubmed/15378679
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  20. //www.ncbi.nlm.nih.gov/pubmed/4397636
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  22. //www.ncbi.nlm.nih.gov/pubmed/9566605
  23. //www.ncbi.nlm.nih.gov/pubmed/383083
  24. //www.ncbi.nlm.nih.gov/pubmed/23458739
  25. //www.koreamed.org/SearchBasic.php?RID=0124KJN/2003.36.9.918&DT=1
  26. //www.sciencedirect.com/science/article/pii/S1756464611000351
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  28. //www.ncbi.nlm.nih.gov/pubmed/17272967
  29. //lib.bioinfo.pl/paper:16003896
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  31. //www.ncbi.nlm.nih.gov/pubmed/9572588
  32. //www.ncbi.nlm.nih.gov/pubmed/3769108


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