L-Theanine: An Amino Acid With Health Benefits

L-Theanine is an amino acid found primarily in the leaves of the tea plant. It has numerous benefits for physical and mental health.
L-Theanine: An Amino Acid With Health Benefits

Last update: 30 November, 2021

L-Theanine is an amino acid found in tea leaves. It was discovered in the 1940s and has a number of important health benefits. In fact, you can find this nutrient in certain foods of plant origin, such as some mushrooms. Some experts attribute properties to it at an organoleptic level. They suggest it provides the umami flavor.

There’s a multitude of amino acids in different foodstuffs. Ensuring the consumption of these nutrients contributes to improving the functioning of your body. Furthermore, each of them affects specific parts of your physiology.

How does L-Theanine work?

In your body, L-Theanine facilitates relaxation and sleep. This happens because it increases the levels of GABA in your body as well as serotonin and dopamine. These neurotransmitters are essential to ensure adequate rest. This fact is evidenced by research published in The International Journal of Biochemistry & Cell Biology.

In addition, L-Theanine can help modulate your moods, concentration, and other sensations such as your appetite. Ensuring a regular supply of it would contribute to an optimal synthesis of neurotransmitters at your brain level. This translates into more efficient internal communication.

On the other hand, another of the properties attributed to L-Theanine is that it takes care of the production of certain of your brain waves. They’re the waves associated with your state of relaxation when you’re awake. In fact, it’s said that specific activities enhance them, such as meditation. In addition, these types of waves are closely related to creativity. For this reason, it’s a really positive step to take care of them.

Sleeping woman

Benefits of L-Theanine

One of the main benefits of L-Theanine is its impact on the quality of your sleep via increased relaxation. According to a study published in Pharmaceutical Biology, its consumption could increase the duration of the REM phase of sleep. This is associated with better rest. Therefore, experts suggest its supplementation is useful in the achievement of optimal sleep.

Scientists have also speculated about the possibility of administering this amino acid to children with attention deficit hyperactivity disorder (ADHD) to help them achieve a deeper and more restful sleep. Although it’s true that the results of the trials aren’t yet confirmed, they’re encouraging.

L-Theanine could also have a positive effect on blood pressure levels. It reduces them. This decreases the incidence of cardiovascular problems.

Doctors have also identified some positive effects of the consumption of this amino acid for people with schizophrenia. That’s because it reduces anxiety. Furthermore, it enhances the attention span and memory of these patients.

Other important dietary points

An adequate supply of L-Theanine isn’t the only dietary requirement you need for optimal levels of sleep. In fact, there are other strategies at the dietary level that experts consider important in terms of rest. For example, they claim that the amino acid tryptophan is important. That’s because it acts as a precursor to serotonin and melatonin. There are several foods that contain tryptophan, such as nuts.

You should also reduce your intake of ultra-processed trans fats and simple sugars. These compounds increase inflammatory states in your body. This means they negatively affect your rest and disrupt your emotional balance. It’s also advisable that you exercise in order to slow down oxidation.

Woman eating salad after exercising

L-Theanine and its relationship with rest and mental health

As you’ve seen, L-Theanine is an amino acid that plays a key role in rest. It’s found mainly in tea and some mushrooms. For this reason, not everyone has it in their diet. However, its inclusion certainly has significant health benefits.

Finally, in order to improve your health, you must combine good life habits with adequate rest. Sports practice is essential. Also, maintain a good diet and avoid the consumption of toxic substances. Finally, don’t forget the importance of frequent exposure to sunlight.

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  • Jones, L. A., Sun, E. W., Martin, A. M., & Keating, D. J. (2020). The ever-changing roles of serotonin. The international journal of biochemistry & cell biology125, 105776. https://doi.org/10.1016/j.biocel.2020.105776
  • Kim, S., Jo, K., Hong, K. B., Han, S. H., & Suh, H. J. (2019). GABA and l-theanine mixture decreases sleep latency and improves NREM sleep. Pharmaceutical biology57(1), 65–73. https://doi.org/10.1080/13880209.2018.1557698
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