How Does L-Theanine Benefit Your Sleep?

A good night’s rest is vital for holistic wellness and everyday enjoyment. Good sleep helps you stay alert, perform your best at work, have energy for exercise, and feel like your best self. In contrast, bad sleep (or not enough sleep) has some not-so-fun side effects. It can leave you feeling groggy, confused, and chronically fatigued. Not to mention, sleep disturbances can mess with more serious things such as your attention span, blood pressure, cortisol levels (stress hormone), your reaction times, and even your emotions and irritability. Your sleep time is very important so you can experience wakeful relaxation each morning!

Unfortunately, many people suffer from low sleep quality, and the duration of their sleep is just not enough. This is undoubtedly exacerbated by our tendency to stay up too late, our workaholic culture, our caffeine intake, and our reliance on electronic devices.

But aside from changing habits or your lifestyle, you may be able to improve your sleep quality, sleep latency, and consistency by using natural sleep aid supplements with L-theanine: a vital amino acid, in more ways than one. Let’s explore  L-theanine and its sleep enhancement benefits.

What Is L-Theanine?

First identified in tea products like long and green tea in 1949, L-theanine is a special amino acid found not only in the aforementioned tea leaves but also in other food products and the human body. 

This amino acid is vital for several bodily processes, especially in the brain. In particular, scientists believe that L-theanine administration can help facilitate sleep by relaxing the mind and causing several neurochemical changes in the brain (almost like it has natural sedative effects). 

While many people have enough L-theanine to sleep soundly, some have difficulty sleeping without supplementary assistance. L-theanine can be found in food products, which can then be consumed before bed for beneficial effects.

Some of the most common teas with high L-theanine content include:

  • Korean Green Tea, with 10.93 mg of L-theanine per gram of tea leaves
  • Hwa Gung, with 12.37 mg of L-theanine per gram of tea leaves
  • Lord Nelson Early Gray, with 1025 mg of L-theanine per gram of tea leaves
  • Vietnamese Green, with 10.11 mg of L-theanine per gram of tea leaves

In addition to tea, L-theanine can be found in various types of mushrooms, broths, and more. Some scientists believe that the “umami” flavor typical of meat-based for savory products comes from L-theanine, at least in part.

How Does L-Theanine Work? 

L-theanine works in several ways to cause neurochemical shifts in the brain. For example, L-theanine:

  • Raises levels of Gamma-Amino Butyric Acid or GABA, a molecule responsible for the levels of serotonin and dopamine in your brain tissue. In other words, it increases the amount of this mood and emotional regulator if it’s currently imbalanced.
  • Boosts the level of other calming brain chemicals, like serotonin.
  • Lowers the level of various excitatory brain chemicals, like cortisol. Such chemicals are linked to anxiousness and stress.
  • Enhances the presence of Alpha brain waves. These unique brain waves are associated not only with REM or rapid eye movement sleep but also with meditation and creativity.

In summary, L-theanine shifts the way the brain operates in the short term and may be able to help your minds settle down into a sleep-ready state at the end of a long day.

L-Theanine’s Effects On Your Sleep Cycles

A full sleep cycle is roughly 90 minutes. Throughout a full sleep cycle, your mind will gradually progress from light sleep into a deep sleep and then rise back into light sleep again. L-theanine is most effective during the first and last stages of a complete sleep cycle.

Normally, our minds gently drift off into the REM stage of sleep as Alpha brain waves increase and our minds settle down. As a complete 90-minute sleep cycle progresses, our brains go into a deep sleep and then rise back into a REM stage of sleep to complete the process.

L-theanine can help your mind drift off to sleep by stimulating the alpha wave brain activity normally experienced in REM sleep. In effect, by calming your brain down and lowering the concentration of excitatory chemicals in mind, L-theanine makes your brain more receptive to sleep.

Because L-theanine has these effects, supplements with this amino acid can help you fall asleep faster and more efficiently. Additionally, L-theanine can help to minimize anxiousness or stress. Many people start worrying about the next day’s responsibilities or mistakes they made during the previous day. L-theanine may help you avoid these thoughts and drift off into sleep without suffering from sleep problems.

However, it’s important to note that L-theanine is not a direct sedative in any way. It promotes relaxation and lowers anxiety levels but doesn’t make you groggy or sleepy by itself.

It’s also crucial to understand that L-theanine alone cannot change your sleep cycle and will not offset unhealthy habits that may affect your sleep readiness.

For example, if you drink a cup of green tea before bed but are on your phone up until you lay down, the L-theanine may not have the intended, sleep-inducing effect.

Additional Benefits of L-Theanine

Aside from being a sleep aid, L-theanine is also known to provide other benefits when taken as a supplement or consumed in green tea, broth, or other foods.

Relief from Stress and Anxiousness

Some individuals choose to prioritize L-theanine in their supplements or diets because they experience higher than average levels of stress or anxiousness. Sipping on a hot cup of tea isn’t just calming because the sensation is soothing to your throat; it may also be calming thanks to the concentrations of L-theanine.

Several trials have indicated that L-theanine is linked with lower anxiousness and stress, even in individuals who experience very stressful situations. 

Improved Focus

L-theanine may also be able to increase your focus, particularly when paired with caffeine. Both molecules are naturally included with green tea, which may explain why many people find that beverage so effective and helpful!

Small concentrations of L-theanine can be particularly helpful for young adults who need to concentrate during demanding or cognitively stressful tasks. But unlike caffeine, L-theanine is not known to make you jittery. The alertness you feel from L-theanine is calmer and steadier, making L-theanine a good supplementary ingredient for those sensitive to caffeine and other stimulants.

Improved Immunity

Furthermore, L-theanine may also be able to boost the function of your body’s immune system. For example, a study recently found that L-theanine may decrease the likelihood of upper respiratory tract infections.

Other studies have indicated that antioxidants, including the catechins found in green tea, can help prevent the flu and similar viral infections. All in all, adding more L-theanine to your diet could provide benefits not only to your sleep quality but also help you feel better overall.


As you can see, doses of L-theanine can help your brain feel calmer and lower the likelihood of anxious or stressful feelings as you drift off into sleep. While it can’t correct bad sleep habits by itself, L-theanine is an important supplement ingredient and can do wonders if you’re having trouble getting your mind to settle down as your head hits the pillow.

Fortunately, you can pick up an effective L-theanine supplement gummy from Hope Health. Our Melatonin Gummies are flavored with healthy botanicals and are effective if you just can’t go to sleep or are trying to support your sleep health.

Try our gummy supplements today to fall asleep and, more importantly, stay asleep with a gentle and effective formula you can’t find anywhere else.



L-theanine, a natural constituent in tea, and its effect on mental state | NCBI

The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent | NCBI

Stages of Sleep | Sleep Foundation

Theanine consumption, stress, and anxiety in human clinical trials: A systematic review | Science Direct

Inhibitory effects of l-theanine on airway inflammation in ovalbumin-induced allergic asthma | NCBI