Does L-Theanine Increase Serotonin and Dopamine?

Updated on January 31, 2024
 by — reviewed by Jason Williams, PhD (Contributor: George Collins / Editor: Yoko Hill)
The influence of L-Theanine on serotonin and dopamine levels explored through surreal art.

Does L-Theanine really increase BOTH serotonin and dopamine?

Serotonin and dopamine are two neurotransmitters that play a crucial role in regulating our mood, emotions, and overall mental well-being. Many people are curious about whether a certain compound, like L-Theanine, can increase the levels of these neurotransmitters in the brain.

In this article, we will explore the scientific research on L-Theanine and its potential effects on serotonin and dopamine levels. We will discuss its cognitive effects and what this amino acid’s potential is in the world of natural nootropics

By examining the factual data, we aim to provide a concise understanding of whether L-Theanine can boost both these vital brain chemicals.

Understanding L-Theanine and Its Effects

L-Theanine is an amino acid that is commonly found in green tea and has gained significant attention for its remarkable effects on the body. This naturally occurring compound is known for its ability to promote relaxation and stress relief.

Originating from the leaves of the Camellia sinensis plant, which is used to produce green tea, L-Theanine has long been recognized for its calming properties and its ability to improve focus and concentration.

When consumed, it crosses the blood-brain barrier and affects the levels of certain neurotransmitters, ultimately leading to a sense of tranquility and mental clarity. This makes L-Theanine a popular dietary supplement for those seeking natural stress relief and improved cognitive function.

Although you can find it in green tea, the best way to take L-Theanine into your body is by incorporating it into your supplementation regimen. Adding L-Theanine into your daily routine allows you to get regulated doses of this essential amino acid consistently.

Some of the key benefits of L-Theanine supplements include:

  • Reduces Stress and Anxiety: L-Theanine treatment has been shown to reduce stress and anxiety levels by increasing alpha waves in the brain, which are associated with a relaxed state of mind. Research has found that L-Theanine can significantly decrease stress and anxiety in various situations, making it a valuable tool for those seeking mental calmness.(1)
  • Improves Sleep Quality: By promoting relaxation, L-Theanine can enhance the quality of sleep. Studies have shown that L-Theanine supplementation improves sleep in both animals and humans.(2) It helps to reduce resting heart rate and create a more relaxed state, which leads to better sleep. If you struggle with insomnia or have difficulty falling asleep, L-Theanine may be a natural remedy worth considering.
  • Enhances Mental Function: L-Theanine has been found to have cognitive-enhancing effects, especially when taken with caffeine. It increases alertness and focus and improves cognitive performance during demanding tasks. Furthermore, L-Theanine has been shown to improve attention and memory in individuals with attention deficit hyperactivity disorder (ADHD).(3) It is a versatile compound that can help sharpen your mental abilities. When used in combination with caffeine supplements, these effects are amplified.(4)
  • Supports Immune Function: Research suggests that L-Theanine may improve immune function. It has been found to reduce upper respiratory tract infections and help prevent the flu.(5) Additionally, L-Theanine has shown potential for improving inflammation in the intestinal tract. While more research is needed to confirm these findings, incorporating L-Theanine into your routine may offer immune-boosting benefits.
  • Provides Relaxation Without Drowsiness: Unlike sedatives, L-Theanine promotes relaxation without causing drowsiness. It can help calm your mind without making you feel tired or groggy. This makes it an ideal option for individuals who want to unwind or reduce stress without the negative side effects associated with sedative medications.

Understanding L-Theanine and its effects can provide valuable insights into harnessing the potential benefits of this amino acid for overall well-being.

The Connection Between L-Theanine, Serotonin, and Dopamine

L-Theanine has gained attention for its potential neuroprotective and cognitive-enhancing effects.

One key aspect of its mechanism of action involves its interaction with neurotransmitters in the brain, particularly serotonin and dopamine.

What are neurotransmitters?

Neurotransmitters are chemical messengers that play a crucial role in communication between nerve cells in the brain. They are involved in various functions, including mood regulation, cognition, and overall brain function.

Serotonin and dopamine are two well-known neurotransmitters that have a significant impact on mood and mental health. Here is a brief overview:

  • Serotonin: Serotonin is often referred to as the “feel-good” neurotransmitter. It is involved in regulating mood, sleep, appetite, and social behavior. Low levels of serotonin have been associated with depression and anxiety disorders.
  • Dopamine: Dopamine is often called the “reward” neurotransmitter. It is involved in motivation, pleasure, and reward-seeking behavior. Imbalances in dopamine levels have been linked to conditions such as Parkinson’s disease and addiction.

Does L-Theanine Raise Serotonin and Dopamine Levels?

L-Theanine (N-ethyl-L-glutamine) is known for its calming effects. Research indicates that L-Theanine works by increasing levels of serotonin and dopamine in the brain, neurotransmitters that play a crucial role in mood regulation.(6) Additionally, L-theanine also boosts GABA levels and interacts with AMPA, Kainate, and NMDA receptors, contributing to its overall relaxing effect.

If we have a closer look, we see that L-Theanine can increase serotonin levels in the brain. Higher serotonin levels are associated with improved mood, reduced anxiety, and increased feelings of well-being. By promoting the release and availability of serotonin, L-Theanine may contribute to mental relaxation and stress reduction.

Similarly, L-Theanine has been found to influence dopamine levels in the brain. It has been shown to increase dopamine release and enhance dopamine receptor activity. This may help improve motivation, attention, and focus.

Overall. the interplay between L-Theanine, serotonin, and dopamine can have several positive effects on brain function:

  • Mood enhancement: By increasing serotonin levels, L-Theanine can promote a positive mood and reduce feelings of anxiety and stress.
  • Stress reduction: L-Theanine’s ability to increase serotonin and dopamine levels can help reduce mental and physical stress, leading to a sense of relaxation.
  • Cognitive enhancement: The influence of L-Theanine on dopamine levels may support improved cognitive function, including attention, memory, and learning.

Potential Side Effects and Considerations

While L-Theanine is considered safe and well-tolerated, there are some potential side effects and considerations to keep in mind when using L-Theanine. Here are five important things to know:

  1. Headaches and Dizziness: In rare cases, some individuals may experience headaches or dizziness when taking L-Theanine supplements. If you notice these symptoms, it is recommended to reduce your dosage or discontinue use. It’s important to note that these side effects are not common, and most people tolerate L-Theanine well.
  2. Gastrointestinal Issues: L-Theanine is gentle on the stomach, but some individuals may experience gastrointestinal issues such as nausea or upset stomach. If you experience any digestive discomfort, try taking L-Theanine with food or reducing your dosage.
  3. Allergic Reactions: While rare, allergic reactions to L-Theanine can occur in some individuals. Symptoms may include itching, hives, swelling, or difficulty breathing. If you experience any signs of an allergic reaction, seek immediate medical attention.
  4. Drug Interactions: L-Theanine is safe to use with most medications. However, it’s always a good idea to consult with your healthcare provider before adding any new supplements to your regimen, especially if you’re taking prescription medications. They can help assess potential interactions and ensure that L-Theanine is safe for you to use.
  5. Safety Considerations: L-Theanine is considered safe for most adults when taken in recommended dosages. However, it’s important to follow the dosage instructions provided by the manufacturer or your healthcare provider. Taking excessive amounts of L-Theanine can disrupt your natural sleep-wake cycle or cause other unwanted effects.

Conclusion: Does L-Theanine Increase Dopamine and Serotonin Levels?

Overall we have verified that L-Theanine has been shown to improve mood and promote relaxation by increasing serotonin and dopamine in the brain.

This powerful amino acid can be found in a cup of green tea, however, the most effective way to obtain L-Theanine is through supplementation. By taking L-Theanine supplements, you can experience the benefits it offers for mood enhancement and stress reduction. 

This could be the answer you’ve been looking for!

As always, remember to consult with a healthcare professional before adding to your regimen.

Sources, Studies, and Scientific Research
  1. Williams, Jackson L et al. “The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review.” Plant foods for human nutrition (Dordrecht, Netherlands) vol. 75,1 (2020): 12-23. doi:10.1007/s11130-019-00771-5 ↩
  2. Dasdelen, Muhammed Furkan et al. “A Novel Theanine Complex, Mg-L-Theanine Improves Sleep Quality via Regulating Brain Electrochemical Activity.” Frontiers in nutrition vol. 9 874254. 5 Apr. 2022, doi:10.3389/fnut.2022.874254 ↩
  3. Lyon, Michael R et al. “The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial.” Alternative medicine review : a journal of clinical therapeutic vol. 16,4 (2011): 348-54. ↩
  4. Anas Sohail, Anas et al. “The Cognitive-Enhancing Outcomes of Caffeine and L-theanine: A Systematic Review.” Cureus vol. 13,12 e20828. 30 Dec. 2021, doi:10.7759/cureus.20828 ↩
  5. Chen, Shuna et al. “L-Theanine and Immunity: A Review.” Molecules (Basel, Switzerland) vol. 28,9 3846. 1 May. 2023, doi:10.3390/molecules28093846 ↩
  6. Nathan, Pradeep J et al. “The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent.” Journal of herbal pharmacotherapy vol. 6,2 (2006): 21-30. ↩