L-Theanine and Sleep

l-theanine sleep supplement

Sleep is an extremely complex process.  High quality L Theanine has been proven to help with certain aspects of sleep and to improve the overall quality of sleep. L-Theanine is interesting in that it’s generally considered to be non-drowsy and helpful for improving mood and focus when taken during the day, yet it is also quite helpful for improving sleep when taken at night.

How does L Theanine improve sleep quality?

L Theanine increases alpha brain wave activity. Alpha brain waves are mainly known to be present during 2 phases.
One time alpha brain wave activity is high is when a person is in a deep state of mental relaxation. This is when their eyes are closed but they are neither drowsy nor sleeping. This is a very deep state of mental relaxation – a state which masters of Zen Buddhism are able to reach.

The other time alpha brain wave activity is high is during REM (rapid eye movement) sleep. REM sleep is one of the 5 phases of sleep and it’s often regarded as the most important phase. Measuring the total amount of time a person sleeps is less important than measuring the quality of a person’s sleep. L Theanine is better known for improving sleep quality. Generally speaking, the more REM sleep a person has, the better the quality. We’ll get to the specific scientific studies on this below.

Another significant way L Theanine works to improve sleep is the effect it has on the inhibitory neurotransmitter GABA. The more GABA in the brain, or the more efficiently GABA is working, the better the sleep quality. GABA is an anxiolytic (anti-anxiety) neurotransmitter. By increasing the effectiveness of the GABA system, L Theanine works to quiet the mind, slow down racing thoughts, and prepare it to drift off into a deep and peaceful sleep.
L Theanine has also been scientifically shown to reduce the edgy or jittery effects from caffeine. So if you are wondering how to counteract or neutralize the effects of caffeine, L Theanine can be a great antidote. And if you drink tea, coffee, cola, or anything caffeinated in the afternoon or evening, L Theanine is a wise choice to help you with your sleep.
Caffeine stays in the system for a long time and the effects can last up to 14 hours. So if you have caffeine at noon, it could still be affecting you by 2 am!

The Science behind L Theanine and Sleep:

Here are a few interesting scientific studies which show L Theanine’s benefits for improved sleep quality.

Study 1:

This study is a direct measurement of alpha brain wave activity from taking L Theanine vs a placebo. We know that alpha brain wave activity is very high during deep meditative states of relaxation, and also during high quality REM sleep.
The study aimed to show that low levels of L Theanine (50mg per day) were enough to produce significant results. The reason they chose such a low amount of L Theanine to study was to see if a realistic dietary intake of L Theanine is enough to make a difference. L Theanine is found naturally in green tea, about 20 mg’s per cup.
The results were such that even 50 mg of L Theanine was enough to significantly increase alpha brain wave activity in subjects resting with their eyes closed, and also when performing moderate activity. There is significant evidence that higher levels of L Theanine (125-250 mg per day) produce even more significant results.
Here is a link to the study

Study 2:

This study from the NIMH actually measured L Theanine’s effects on sleep quality. The researchers looked at 22 young men (12 daytime workers and 10 students). They gave half of them 200 mg of L Theanine each day for 6 days, and the other half a placebo. Then they switched the groups.

The researchers gave everyone interviews and questionnaires upon waking. They also hooked all of their wrists up to a device which measures movements during the night. What they found was quite amazing:

They found that the people in the L Theanine group experienced a much better quality of sleep. 

The people who took L Theanine woke up more refreshed and were “less exhausted” than subjects in the placebo group. The subjects actually reported this during their interviews and in their questionnaires.
This clearly indicates that they had a better sleep quality, even though they didn’t sleep any longer than those in the placebo group; they just slept better.

Another huge benefit was that the people who took L Theanine reported both better mental states before falling asleep, and also experienced significantly fewer nightmares.

Study 3:

Here was a recent crossover study that looked at several benefits of l theanine compared to placebo.  They gave participants 200 mg of l theanine or an identical looking placebo. 

The way they measured sleep was assessed using the Pittsburgh Sleep Quality Index (PSQI). 

They concluded:

“The reduction in sleep quality problems (disturbances in sleep latency, sleep disturbance, and use of sleep medication) was greater in the L-theanine administration compared to the placebo administration”

Study 4:

Another double blind study looked at subjects with general anxiety disorder.  They took relative high dose l theanine (450 – 900) mg per day, along with their current antidepressant medication.  

One conclusion of the study was:

Participants treated with l theanine “reported greater self-reported sleep satisfaction than placebo”

Study 5:

This double blind study looked at boys, aged 8 – 12 years old, with ADHD.  

They took 200 mg of l theanine (twice daily) or a placebo. 

The study results showed that:

“Actigraph watch data findings indicated that boys who consumed L-theanine obtained significantly higher sleep percentage and sleep efficiency scores”

These studies are great to view in conjunction with one another. The first study shows that L Theanine actually increases alpha brain waves on a physical level, which would indicate a better sleep from more time in REM sleep, explain the potential for fewer nightmares, and also predict a better state of mind before drifting off to sleep. This is all due to what we know about increased alpha brainwave activity. See above.

The second study backed it up by actually asking people through interviews and questionnaires how they felt and what they experienced from taking L Theanine before bed.

The subjects in this study experienced what the first study would have predicted; better quality and more REM sleep, less nightmares, a better and calmer mindset before sleeping.

And most of all, the people who took L Theanine before sleeping reported feeling “less exhausted” and more “well rested” upon waking – basically the definition of improved sleep quality.

The final 2 studies indicate that l theanine can be useful as an adjunct sleep therapy, even in patients who have conditions that would typically make them more likely to have sleep problems (eg. people with general anxiety disorder or boys with ADHD)

What is an ideal dose when using L Theanine for sleep?

Stating the absolute right dose of L Theanine for sleep is impossible to say with 100% certainty. It’s not a “one size fits all” type of thing, and this depends on many factors. The way doses are normally recommended is based from the relatively few studies done on the subject. What we do know is that even doses as low as 50 mg per day could have a significantly positive effect on sleep. More studies on L Theanine and sleep have looked at doses in the range of 200-250 mg per day.  Some studies, as mentioned above, even go up to 900 mg per day (This is a much higher than normal dose, but it does help to indicate that l theanine is safe and well tolerated)

Where to buy high quality l theanine for sleep?

We use a pharmaceutical grade l theanine that has been a huge hit with our customers all over the world.  We use pure veggie caps and no fillers.


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