L-Theanine Dosage Guide

L-Theanine Dosage Guide

L-Theanine, an amino acid found primarily in green tea leaves, has gained popularity in recent years for its potential health benefits, particularly in promoting relaxation and reducing stress.

As more people turn to natural remedies for managing their well-being, understanding the appropriate dosage of L-Theanine is crucial for maximizing its benefits without experiencing adverse effects.

In this article, we will explore its optimal dosage.

L-Theanine Dosage Guide: How Does L-Theanine Work?

Upon ingestion, L-Theanine crosses the blood-brain barrier and increases the production of various neurotransmitters, including GABA, serotonin, and dopamine, which are key regulators of mood, relaxation, and focus. L-Theanine is one of the amino acids found in green tea, comprising a significant portion of the amino acids in green tea leaves and existing in the free form.

By enhancing the levels of these neurotransmitters, L-Theanine promotes a sense of calmness and relaxation without inducing drowsiness, making it an effective tool for managing stress and anxiety.

Additionally, L-Theanine has been shown to increase alpha brain wave activity, which is associated with a relaxed yet alert mental state, further contributing to its cognitive and stress-relieving properties.

The Health Benefits of L-Theanine

L-Theanine has been the subject of numerous studies due to its potential health benefits. These benefits range from enhancing cognitive performance and reducing physical and psychological stresses to supporting cancer treatment.

Mental Focus and Cognitive Performance

L-Theanine’s impact on mental focus and cognitive performance is notable due to its ability to influence brain chemistry and function. Research suggests that L-Theanine promotes increased alpha brain wave activity, which is associated with a relaxed yet alert mental state. By enhancing alpha wave production, L-Theanine can improve attention and focus while simultaneously reducing feelings of stress and anxiety.

When combined with caffeineL-Theanine has been shown to synergistically enhance cognitive function, leading to improved attention, reaction time, and task-switching abilities. This combination is particularly beneficial as it mitigates the potential negative effects of caffeine, such as jitteriness and increased heart rate, while amplifying its positive cognitive effects. Studies highlight how caffeine improves cognitive performance, especially when used in conjunction with L-Theanine, enhancing both mood and cognitive tasks performance.

In a systematic review, Sohail et al. (2021) found that the combination of caffeine and L-Theanine improved short-term sustained attention and overall cognition. Reversed task-related mind-wandering and improved inhibitory control were also seen among boys with attention deficit hyperactivity disorder (ADHD). These findings underscore the potential therapeutic applications of L-Theanine in addressing cognitive challenges, particularly in populations with attention-related disorders. The combination's effect on human cognition has been extensively studied, showing significant benefits in cognitive performance, attention, and mood.

Sleep and Relaxation

L-Theanine's impact on sleep quality and relaxation stems from its ability to modulate neurotransmitter activity in the brain, particularly by increasing levels of GABA, serotonin, and dopamine. GABA is known for its calming effects on the nervous system, promoting relaxation and reducing feelings of stress and anxiety. By enhancing GABA levels, L-Theanine helps induce a state of relaxation without causing drowsiness, making it conducive to both relaxation and sleep.

The amino acid has also been found to increase the production of alpha brain waves, which are present when the mind is in a calm and relaxed state, such as during meditation or deep relaxation.

A 2018 clinical study found that participants reported greater sleep satisfaction after taking 450–900 mg of L-Theanine daily for eight weeks. To further consolidate the effects of L-Theanine on sleep quality, a study by Kim et al. (2019) found that a GABA/L-Theanine mixture could be used to treat insomnia and sleep disorders as a concept of nonpharmacological management of sleep.

These findings underscore the multifaceted effects of L-Theanine, not only in enhancing relaxation and sleep quality but also in offering potential solutions for addressing sleep disturbances.

Reducing Anxiety and Stress

By increasing the levels of GABA, serotonin, and dopamine, L-Theanine promotes a sense of relaxation and calmness, thereby reducing stress-related symptoms such as elevated heart rate and cortisol levels (stress hormone). This is evident as Kimura et al. (2007) found that L-Theanine reduces psychological and physiological stress responses, including a reduction in the heart rate and salivary immunoglobulin A responses.

Research also suggests that L-Theanine may be particularly beneficial for individuals with anxiety disorders, including generalized anxiety disorder (GAD) and social anxiety disorder (SAD). Studies have shown that L-Theanine supplementation can lead to a reduction in anxiety symptoms and improve overall well-being without causing sedation or impairment of cognitive function.

L-Theanine administration has been shown to alleviate symptoms of depression, such as low mood, anhedonia, and feelings of hopelessness, by promoting a sense of relaxation and calmness without causing sedation. For example, Hidese et al. (2017) found that eight weeks of L-Theanine administration had multiple beneficial effects on depressive symptoms, anxiety, sleep disturbance, and cognitive impairments in patients with major depressive disorder.

Therefore, taking L-Theanine offers a promising natural solution to reducing anxiety levels and alleviating symptoms of depression without causing sedation or cognitive impairment.


L-Theanine Dosage

Understanding supplements can be challenging, especially when it comes to determining the right dosage. This is particularly true for L-Theanine. While there's no one-size-fits-all dosage, there are some general recommendations and specific guidelines for certain conditions.

Dosage for Specific Conditions

L-Theanine dosage can vary based on the specific condition it’s being used to address. Here are a few examples:

  1. Cardiovascular Health: To manage caffeine-induced stress and blood pressure, doses of 50mg or 200 mg have been used in healthy adults. This dosage helps to moderate the effects of caffeine on heart rate and blood pressure.

  2. Schizophrenia: As an adjunct to antipsychotic medication, L-Theanine doses of 250 mg/day or 400 mg/day for eight weeks have been studied. This dosage showed potential in improving psychopathology scores in patients with schizophrenia.

  3. General health and wellness: The optimal dosage of L-Theanine for general health and wellness, a typical L-Theanine dosage is between 100-200 mg per day. NMN Bio’s NAD+ Brain supplement contains 100 mg of L-Theanine per serving, offering a convenient way to incorporate this beneficial amino acid into your daily routine for enhanced cognitive support and stress management.

  4. Anxiety: For immediate relief from acute anxiety symptoms, a single dose of 200-400 mg of L-Theanine may help promote relaxation and reduce stress.

  5. Long-term anxiety: For longer-term anxiety conditions like GAD, daily doses of L-Theanine may be more effective in managing symptoms over time. However, larger doses are also more likely to cause side effects like headaches, nausea, and dizziness.

These are just guidelines. Always consult with your healthcare provider before starting any new supplement regimen. They can provide personalized advice based on your specific health circumstances. The dosages recommended for specific conditions are often derived from placebo controlled clinical trials.

Potential Side Effects of L-Theanine

  • Generally considered safe when consumed in appropriate doses

  • Rare reports of mild side effects such as headaches, dizziness, and gastrointestinal discomfort

  • May interact with certain medications, particularly those affecting blood pressure or mood

  • High doses may lead to excessive relaxation or drowsiness

  • Individuals with specific health conditions, such as low blood pressure or bipolar disorder, should exercise caution and consult a healthcare professional before use

How to Consume L-Theanine: Tea vs Supplements

L-Theanine is naturally present in green tea leaves, contributing to its unique flavor and calming properties. A cup of green tea contains around 20 mg of L-Theanine. However, this amount can vary based on factors like the type of green tea and brewing time. 

So, while green tea is a great source of L-Theanine, supplements can be a more reliable way to meet your daily needs. L-Theanine supplements, such as NMN Bio's NAD+ Brain supplement, offer a concentrated dose of this beneficial amino acid, ensuring you get the right amount for optimal health benefits. To really utilise the adaptogenic benefits of L-Theanine, you might want to titrate your supplement dosage to your individual needs. NAD+ Brain also contains 25mg of caffeine per capsule, so depending on how much caffeine you are used to, you might want to start from the recommended serving size.

The suggested serving size of NAD+ Brain is two capsules, however, you have the flexibility to consume anywhere from one to seven capsules daily. Initially, begin with two capsules per day to gauge your response and performance. 

FAQs about L-Theanine

Navigating the world of supplements can be a daunting task, especially when it comes to understanding the right dosage and timing. In this section, we aim to address some of the most frequently asked questions about L-Theanine, a popular supplement known for its calming effects. We'll delve into its daily intake and the optimal time to take it for anxiety relief.

Is it safe to take L-Theanine every day?

Sure, taking L-Theanine daily is generally considered safe. It's a natural compound found in tea leaves, after all. But, like with anything, moderation is key.

Overdoing it might lead to some side effects like headaches or dizziness. But these are rare and usually happen with high doses.

So, if you're thinking about taking L-Theanine every day, it's a good idea to start with a low dose. Then, you can gradually increase it if needed.

But remember, everyone's body is different. What works for one person might not work for another.

So, it's always a good idea to check with your doctor before starting any new supplement regimen. They can help you figure out the right dosage for you.

In a nutshell, yes, it's safe to take L-Theanine daily. But, as always, moderation and medical advice should be your guiding principles.

When is the best time to take L-Theanine for anxiety?

If you're dealing with anxiety, L-Theanine can be a great help. But when should you take it? Well, it's suggested to split your dosage into two parts. One in the morning, say with your breakfast, and the other one at night, perhaps with your dinner. Each dose could be around 100 mg. This way, L-Theanine can work throughout the day to keep your anxiety in check. But remember, if you're anticipating a stressful event like a public speaking gig or an exam, taking L-Theanine 30-60 minutes before can be really helpful. It's like giving your brain a little extra support to handle the stress.

Final Thoughts on L-Theanine

The benefits of L-Theanine consumption are extensive and multifaceted, ranging from the modulation of brain chemicals to the improvement of mental and physical health outcomes. By influencing the levels of key neurotransmitters, L-Theanine can have acute effects on the brain, leading to increased relaxation, improved focus, and reduced stress. These benefits are particularly relevant for individuals looking to treat anxiety and manage stress-related symptoms in a natural and effective way.

Green tea consumption serves as a natural source of L-Theanine, offering a synergistic blend of compounds that enhance overall well-being. However, for those seeking more pronounced effects, supplementation may provide a more targeted approach to managing anxiety levels and optimizing cognitive function.

Ultimately, L-Theanine represents a promising natural compound for those interested in exploring alternative methods to enhance their mental health and cognitive performance. Whether through green tea consumption or as a supplement, L-Theanine offers a safe and beneficial option for individuals aiming to treat anxiety, improve brain health, and support a balanced mood through the natural modulation of brain chemicals. The benefits of L-Theanine, especially when combined with caffeine, have been thoroughly researched, including caffeine stimulation evaluated on cognitive performance and mood.

For those interested in exploring the benefits of L-Theanine further, NMN Bio’s NAD+ Brain supplement contains 100 mg of L-Theanine per serving, offering a convenient way to incorporate this beneficial amino acid into your daily routine for enhanced cognitive support and stress management.

Researched and reviewed by Dr Elena Seranova, Ph.D.

Dr Seranova holds a master’s degree in Translational Neuroscience from the University of Sheffield, UK, and a Ph.D in Stem Cell Biology and Autophagy from the University of Birmingham, UK. She is a published author in multiple peer-reviewed journals, including Cell Reports and Developmental Cell.


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