L-Theanine Sleep Dosage: How It Improves Sleep

L-Theanine Sleep Dosage: How It Improves Sleep

In today's fast-paced world, sleep often takes a back seat to the demands of daily life. According to a report by the Centers for Disease Control and Prevention (CDC), only 65% of adults report a healthy duration of sleep. This lack of sleep can have significant impacts on their overall health and well-being. However, natural supplements can help improve sleep quality, one of which is L-Theanine.

In this article, we will explore the benefits of L-Theanine for sleep and discuss the optimal dosage for achieving maximum results.

What is L-Theanine?

L-Theanine is a naturally occurring amino acid found primarily in tea leaves, particularly in green tea. It is known for its relaxing and calming effects, making it a popular choice for reducing stress and promoting relaxation. L-Theanine works by increasing levels of neurotransmitters such as GABA, serotonin, and dopamine, which are associated with feelings of relaxation and well-being.

How L-Theanine Can Help You Sleep

L-Theanine has been linked to improved sleep quality in several studies. Its unique impact on brain chemicals influences sleep patterns making it a potential sleep aid. Not only does it help individuals fall asleep more easily, but it also enhances the quality of sleep by increasing sleep efficiency and the duration of REM sleep, the stage where most dreaming occurs.

L-Theanine and Relaxation

Several studies have validated L-Theanine's ability to promote relaxation. For example, a study by Williams et al. (2016) found that doses of 250 mg and 400 mg of L-Theanine greatly improved sleep in animals and humans. They further discovered that 200 mg of L-Theanine reduced resting heart rate, indicating its ability to promote relaxation. This is crucial for sleep, as a relaxed state of mind is a prerequisite for a good night's sleep.

L-Theanine works by influencing neurotransmitters, the body's chemical messengers, rather than building proteins like other amino acids. The amino acid has been shown to increase levels of gamma-aminobutyric acid (GABA), a neurotransmitter known for its calming effects on the brain. GABA helps to regulate neuronal excitability, promoting a state of relaxation and reducing feelings of stress and anxiety.

The amino acid also affects serotonin and dopamine levels in the brain. Serotonin is a neurotransmitter that plays a key role in mood regulation, while dopamine is associated with feelings of pleasure and reward. By modulating the activity of these neurotransmitters, L-Theanine can help promote a sense of well-being and relaxation.

L-Theanine and REM Sleep

L-Theanine's impact on REM sleep is a significant factor in its sleep-enhancing properties. REM sleep, the stage of sleep where most dreaming occurs, is crucial for cognitive function and overall health. Studies have shown that L-Theanine can increase the amount of time spent in this vital sleep stage.

For example, a 2019 clinical study found that a GABA/L-Theanine mixture (100/20 mg/kg) showed a decrease in sleep latency and an increase in sleep duration. The combination led to a significant increase in rapid eye movement (REM) (99.6%) and non-REM (NREM) (20.6%) compared to controls.

L-Theanine contributes to a more restful and rejuvenating REM sleep phase by increasing GABA levels and influencing serotonin and dopamine. 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. This provides further evidence for its potential to facilitate a deeper and more tranquil REM sleep phase.

L-Theanine and Sleep Quality

L-Theanine has garnered attention for its potential to enhance sleep quality. By increasing levels of neurotransmitters like GABA, while influencing serotonin and dopamine activity, L-Theanine promotes relaxation and reduces stress and anxiety, facilitating faster sleep onset and deeper, more restful sleep. Its ability to boost alpha brain waves, indicative of a calm and relaxed mental state, further contributes to its efficacy in improving sleep quality.

A 2018 clinical study found that participants reported greater sleep satisfaction after taking 450–900 mg of L-Theanine daily for 8 weeks. This suggests that L-Theanine can improve sleep quality over time, rather than just having a one-off effect.

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.

However, it's important to note that the effects of L-Theanine on sleep quality may vary from person to person, and more research is needed to fully understand its potential benefits.

Other Health Benefits of L-Theanine

Recommended L-Theanine Dosage for Sleep

Research suggests that doses ranging from 100 mg to 400 mg can be beneficial for sleep. It's generally advised to start with the smallest suggested dose and gradually increase it until you notice an effect. The exact dosage may vary depending on individual needs.

It's important to note that a single dose of L-Theanine will have a limited effect, and studies have generally measured results between 4 and 8 weeks. Therefore, consistent use over a period of time is key to experiencing the full benefits.

Sources of L-Theanine

L-Theanine is primarily found in tea, specifically green and black tea. The Camellia sinensis plant, more commonly known for producing green, black, white, or oolong teas, is the primary source of this compound.

The amount of L-Theanine in a serving of tea can vary, depending on the quantity of tea leaves used and the steeping duration. On average, a serving of tea contains about 25 to 60 milligrams of L-Theanine, with green teas typically having slightly higher levels than black teas.

While tea remains the primary natural source of L-Theanine, it's worth noting that this amino acid has also been identified in some types of mushrooms. However, the concentration of L-Theanine in mushrooms is lower compared to that in tea leaves.

L-Theanine is also available as a supplement. Per serving of two capsules, NMN Bio's NAD+ Brain contains 100 mg of L-Theanine to promote calm and focus and 50 mg of apigenin, a potent natural compound known for its calming effects on brain cells and its ability to preserve NAD+. You can take anywhere from one to seven capsules per day, making it a suitable supplement for sleep hygiene. NAD+ Brain is take in the morning, as it contains caffeine, but due to it's anti-inflammatory properties for the brain, we've seen deeper sleep, decreased resting heart rate (meaning better physical and cognitive recovery), and increased REM and overall sleep time. 

While L-Theanine supplements are generally considered safe for most people, they should be used with caution in certain populations. For instance, pregnant or breastfeeding women, individuals with low blood pressure, and children should consult with a healthcare provider before starting any new supplement regimen.

Potential Side Effects of L-Theanine Supplements

While taking L-Theanine is generally well-tolerated, it's crucial to be aware of potential side effects. Although rare, some individuals may experience:

  • Headaches
  • Dizziness
  • Upset stomach
  • Drop in blood pressure
  • Nausea

Interactions with Other Medications

L-Theanine, while generally safe, may interact with certain medications, potentially altering their effectiveness or causing unexpected side effects. For instance, those on high blood pressure medication should exercise caution. L-Theanine could potentially amplify the effects of these drugs, leading to an unsafe drop in blood pressure.

Stimulant medications, often used to treat conditions like attention deficit hyperactivity disorder, may also interact with L-Theanine. The calming effects of L-Theanine could potentially counteract the intended effects of these stimulants, leading to decreased efficacy.

In all cases, it's crucial to consult with a healthcare provider before starting L-Theanine, especially if you're currently on any medication. They can provide personalized advice based on your health history and current medications.

The Impact of L-Theanine on Sleep

L-Theanine emerges as a promising natural solution to improve sleep quality. Its ability to promote relaxation, influence neurotransmitter activity, and enhance REM sleep underscores its potential as a valuable sleep aid. Supported by scientific evidence and centuries of traditional use in tea, L-Theanine offers a gentle yet effective approach to achieving restful and rejuvenating sleep.

NMN Bio's NAD+ Brain contains 100 mg of L-Theanine per serving to promote calm and focus. The supplement, in general, enhances mood and cognitive performance and supports long-term brain health. Take from one to seven capsules per day in the morning to improve your sleep. NAD+ Brain is considered a much better and healthier alternative to coffee, as it provides both short-term effects of focus and concentration within 20 minutes, and long-term benefits of slowing down the aging process in the brain. 

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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