Does L Theanine Make You Sleepy?

L-theanine helps support sleep but is not a powerful sedative. Instead of directly acting as a sedative, L-theanine helps relax the mind and reduce anxiety, thereby allowing sleep to come naturally. For many people, L-theanine can help improve sleep quality, especially with stress or insomnia.

However, not everyone fully understands how L-theanine works or whether it can help you fall asleep as easily as other supplements. Let's explore whether L-theanine can help you sleep better and what benefits it offers through the article below.

What Is L-Theanine?

L-theanine is a natural amino acid primarily found in tea leaves, especially green tea, and some types of mushrooms. It plays a crucial role in the body's biological processes, contributing to protein synthesis and potentially influencing brain function and mental health.

L-theanine affects various chemical compounds in the brain, particularly through interactions with glutamate, another amino acid that helps transmit nerve signals in the brain. In some cases, L-theanine can mimic glutamate, while in other situations, it may block the effects of glutamate.

This flexible interaction helps L-theanine provide calming effects, as it also influences other important neurotransmitters in the brain, such as GABA, dopamine, and serotonin — chemicals related to mental health and alertness [1].

Where L-Theanine Is Found?

L-theanine occurs naturally in several food sources, most notably green tea and some types of mushrooms:

Tea

Green tea contains the highest amount of L-theanine, with approximately 6.56 mg of theanine per gram of tea [2]. Black tea also contains L-theanine, but usually in smaller amounts than green tea. The ratio of caffeine to theanine in green tea is lower than in other teas, which may explain why green tea induces a relaxed feeling despite containing caffeine.

Mushrooms

Some mushrooms, particularly those in the Boletus family, also contain L-theanine, but mushrooms are not as common a food source as tea.
In addition to these natural sources, L-theanine is also available as a supplement, allowing users to easily supplement with a controlled, higher dose. However, if you want to incorporate L-theanine into your diet, enjoying a cup of green or black tea daily is the simplest and most effective choice.

Does L-Theanine Make You Sleepy?

The answer is yes. L-theanine is known for its ability to promote relaxation and improve sleep quality, although it does not make you feel sleepy directly like some sedatives. However, some studies suggest that L-theanine can help you fall asleep more easily and experience deeper sleep [3]. This effect primarily stems from L-theanine's impact on brain chemicals involved in sleep regulation.

How Does L-Theanine Affect Sleep?

L-theanine has a special effect on sleep, primarily through its impact on neurotransmitters and the stimulation of brain activity to promote relaxation. Some of the ways L-theanine affects sleep include:

Impact on neurotransmitters

L-theanine works by crossing the blood-brain barrier, affecting several neurotransmitters in the central nervous system. One of the main ways L-theanine works is by interacting with glutamate. Animal studies have shown that L-theanine can block glutamate from binding to brain cells, reducing the excitatory effects of glutamate and decreasing brain activity, which helps create the relaxed state necessary for sleep [5].

In addition, L-theanine also helps boost calming neurotransmitters like gamma-aminobutyric acid (GABA), serotonin, and dopamine, contributing to emotional regulation, relaxation, and supporting sleep.

Stimulating brainwave activity

L-theanine's effect on brain wave activity is also crucial in promoting sleep. Research indicates that L-theanine can enhance the production of alpha brainwaves, which occurs when we are relaxed but still awake [4]. Alpha waves are also common during REM sleep and light sleep. By stimulating alpha waves, L-theanine helps create a state of relaxation, focus, and calm, making it easier to fall asleep.

Relaxation without drowsiness

One of the advantages of L-theanine is that it promotes relaxed alertness, causing less drowsiness compared to other sedatives. Simply put, you can enjoy relaxation without worrying about feeling sluggish or tired when using this compound.

Benefits of L-Theanine for Sleep

Improving Sleep Quality

L-theanine can help improve sleep quality indirectly by promoting relaxation and reducing stress. While L-theanine does not directly cause drowsiness, it can help you fall asleep more easily and enjoy deeper sleep. Studies have shown that L-theanine can reduce nighttime awakenings and support recovery from fatigue, making you feel more alert upon waking.

L-theanine also helps those with stress and those taking antidepressants feel improved sleep quality. A 2018 study showed that participants were satisfied with their sleep after using L-theanine daily for 8 weeks, although there were no significant improvements in stress levels or insomnia [6].

Reducing Stress

L-theanine is effective at reducing stress due to its ability to increase neurotransmitters like GABA, dopamine, and serotonin, creating relaxation and maintaining deeper sleep.

L-theanine also helps reduce symptoms of stress, such as lowering heart rate and blood pressure. Research has shown that L-theanine may reduce stress in people with mental disorders like schizophrenia and schizoaffective disorder [7].

A 2019 study demonstrated that L-theanine could reduce stress symptoms in healthy adults after 4 weeks [8]. While the degree of stress reduction may vary among individuals, L-theanine is widely recognized for calming the nervous system and encouraging relaxation.

Support Weight Management

L-theanine not only helps improve sleep but also indirectly supports weight management. Stress and poor sleep are often linked to weight gain and unhealthy eating habits. By reducing stress and improving sleep quality, L-theanine helps maintain a healthy lifestyle and supports weight control.

Moreover, some studies have shown that L-theanine may help reduce fat accumulation, supporting the body in managing the negative effects of stress on health and weight [9].

Enhance Focus & Mental Health

When the body is stressed, hormones like cortisol can impair memory and learning ability. L-theanine helps reduce the levels of these stress hormones, thereby supporting memory improvement and learning ability.

Research indicates that L-theanine can enhance focus, reduce reaction times, and improve accuracy in thinking, especially for those prone to stress. When combined with caffeine, L-theanine can help improve cognitive performance and increase information processing ability [10].

Should You Take L-Theanine for Sleep?

L-theanine should be used to support relaxation before sleep or when you feel stressed or anxious, as these factors can affect sleep quality.

L-theanine does not directly cause drowsiness but helps create an ideal relaxed environment for falling asleep and recovering energy. By affecting glutamate receptors, L-theanine can help reduce stress and improve sleep without making you feel sleepy during the day.

Although some preliminary studies suggest that L-theanine may help extend sleep duration and reduce sleep disturbances when combined with other minerals like magnesium [11], more research is needed to confirm its effects in humans. Before using L-theanine, you should consult your doctor to rule out any underlying medical conditions like sleep apnea or chronic insomnia.

How to Use L-Theanine for Sleep

How Much L-Theanine for Sleep?

Although there is no "perfect" dosage of L-theanine for everyone, studies suggest that 200 mg of L-theanine per day is an effective dose for supporting sleep [12]. Some studies have even tested doses up to 400-500 mg per day, with results indicating it is safe for healthy adults [13].

If you are new to L-theanine, start with a lower dose (e.g., 100 mg to 200 mg) and gradually adjust according to your body’s response. It is important to consult a doctor before starting any supplementation regimen to ensure that L-theanine is appropriate and safe for your health, especially if you have underlying health conditions.

What is the Best Time to Take L-Theanine for Sleep?

There are several good times to take L-theanine to improve sleep quality. Many people find the following times ideal:

• Before bed (30-60 minutes before sleep): This is the ideal time to help you sleep well and reduce nighttime awakenings.
• In the evening (a few hours before bed): Taking L-theanine slightly earlier helps with relaxation and stress relief after a long day.
• In the morning or afternoon (when needed): If you need to reduce stress during the day, you should take L-theanine in the morning or early afternoon.

The timing of L-theanine usage can vary depending on individual needs, but to improve sleep quality, it’s best to take L-theanine about 30 to 60 minutes before bed. This timing is sufficient for L-theanine to cross the blood-brain barrier and take effect as you prepare to fall asleep.

Possible Side Effects of L-Theanine You Need to Know

L-theanine is recognized by the U.S. Food and Drug Administration (FDA) as a safe food ingredient when used up to 250 mg per dose. Higher doses may cause some side effects, such as:

• Liver issues: Some people have reported that green tea extract, a common source of L-theanine, can cause liver problems.
• Low blood pressure: L-theanine may lower blood pressure, so those with low blood pressure should consult a doctor before using it.
• Interaction with caffeine: Caffeine may reduce the relaxing effects of L-theanine due to symptoms like restlessness and insomnia, which the compound often causes.
• Caution with children: L-theanine can be safe for children at low doses, but tea should not be used as a source of L-theanine. If you plan to give L-theanine to children, consult a doctor first.
• Pregnant and breastfeeding women: It is best to avoid using L-theanine during pregnancy or breastfeeding to ensure safety.

L-Theanine Interactions

Similar to other compounds, L-theanine can interact with certain medications, such as:

• Antihypertensive drugs: L-theanine has a natural blood pressure-lowering effect, so combining antihypertensive medications with L-theanine may cause your blood pressure to drop too much.
• Stimulants: Stimulant drugs, such as those used for ADHD or narcolepsy, may have their effects reduced when combined with L-theanine or may alter the body’s sensations.
• GABA-related medications: L-theanine can increase GABA levels, so combining it with medications like benzodiazepines (e.g., Xanax, Valium) or other sedative drugs may enhance their calming effects, potentially causing excessive drowsiness or other side effects.
• Cancer medications: L-theanine may affect the immune system and cell activity, and since the interaction between L-theanine and cancer drugs has not been thoroughly researched, it is best to avoid using them together.
• Other medications: It is important to avoid combining L-theanine with other medications such as anticonvulsants, asthma medications, antidepressants, and blood thinners.

Other Supplements for Sleep You Can Choose

If you are looking for other supplements to improve sleep aside from L-theanine, here are a few options you can consider:

• Melatonin: Supplementing with melatonin can be helpful for those with sleep problems, especially for jet lag or shift work.
• Magnesium is an important mineral that helps relax muscles and calm the nervous system. Supplementing with magnesium may help reduce stress, relax the body, and make it easier to fall asleep.
• Valerian Root: Valerian root calms the nervous system and reduces stress, helping you relax before sleep.
• Chamomile: Chamomile tea is known for its relaxing properties and can help you fall asleep more easily.
• Lavender: Lavender essential oil is known for its ability to reduce stress and promote sleep.
• GABA: GABA supplements can help calm the mind, reduce restlessness, and improve sleep quality.

Conclusion

In conclusion, L-theanine is a great choice to reduce stress and improve sleep quality, but it is not as powerful in inducing sleep as melatonin. Instead, L-theanine helps relax the body and mind, allowing sleep to come naturally. If you are looking for a natural way to support sleep without feeling immediately drowsy, L-theanine may be the right choice. However, optimal results should be combined with a healthy lifestyle and a proper sleep routine.