Unlocking the Benefits of L-Theanine: A Comprehensive Guide - HONE
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Unlocking the Benefits of L-Theanine: A Comprehensive Guide

In today's fast-paced world, stress and anxiety are on the rise. But what if there was a natural way to reduce these feelings, improve cognitive function, and get an abundance of other benefits?

Enter L-theanine, an amino acid found in green tea leaves and matcha. In this guide, we’ll take a detailed look at the many benefits L-theanine can offer.

Article Jumplinks:

What does L-theanine do?

What are the benefits of L-theanine?

What are the negative effects of L-theanine?

Does L-theanine interact with medications?

Can I take L-theanine with caffeine?

How can I take L-theanine?

What Is L-Theanine?

L-theanine is an amino acid that occurs naturally in green tea (Camellia sinensis), matcha, black tea (Camellia sinensis assamica), and bay bolete mushrooms (Xerocomus badius).

Whether you’re looking to reduce stress and anxiety, improve focus, or just improve your overall wellbeing, L-theanine can help achieve that and more. Our matcha and cordyceps tea blend is chock-full of this amazing amino acid. 

What Does Taking L-Theanine Do?

L-theanine has calming properties, which come as a result of its antagonistic (blocking) effects on glutamate receptors. Excess glutamate is associated with high brain excitation, which can cause stress, anxiety, and even schizophrenia. By blocking glutamate receptors, L-theanine may alleviate the symptoms of these mental health conditions.

L-theanine also appears to increase alpha waves in the brain, which enhances its anti-stress effects. Alpha brain waves are electrical wave patterns in the brain and are prominent during quiet thoughts and meditative states.

Neuroscientists have linked these alpha oscillations to improved mental coordination, creativity, calmness, alertness, and mind-body integration and learning. On top of this, when alpha waves are prominent, your mind is generally clear of unwanted thoughts, and sensory inputs tend to be minimized.

L-Theanine Chemical Composition

What Foods Are Rich in L-Theanine?

Green tea and matcha contain the most L-theanine. Because of the different preparation processes, which allow more of the compound to be extracted, you will get more of this amino acid through matcha than you do when drinking green tea. Black tea and some mushroom types also contain L-theanine, but at lower doses.

L-Theanine Benefits

People with various ailments, as well as healthy adults and children, can all benefit from L-theanine consumption. Here are some of the key benefits of L-theanine:

  • provides neuroprotective effects
  • reduces stress and anxiety
  • improves cognitive performance
  • promotes sleep quality
  • aids in blood pressure regulation
  • protects against cancer

Mental Health Benefits of L-Theanine

L-theanine is one of the best supplements you can take for mental health. This compound is thought to cross the blood-brain barrier and counteract psychological stresses within 30 minutes of consumption. 

L-Theanine for Depression

2016 study looked into the possible benefits of L-theanine in the treatment of major depressive disorder (MDD).

The Hamilton Depression Rating Scale (HAMD-21) was administered to participants at baseline, as well as after 4 and 8 weeks of L-theanine administration.

Participants on L-theanine had significantly improved HAMD-21 scores compared to the control group, indicating that L-theanine treatment improves symptoms of depression.

L-Theanine for Anxiety

The effects of L-theanine on stress and anxiety symptoms have been widely researched. A 2016 randomized, controlled trial investigated the effects of this compound on stress and concluded that it significantly reduced stress responses in human, adult subjects.

Another placebo-controlled trial, published in 2019, looked at the effects of L-theanine on anxiety in humans. 46 participants with diagnosed generalized anxiety disorder were given from 450 to 900 mg of L-theanine, or a placebo.

Those given the supplement reported feeling and sleeping better, which suggests that L-theanine administration could aid in the treatment of anxiety. 

L-Theanine for ADHD

The effects of L-theanine on attention deficit hyperactivity disorder (ADHD) were researched in a 2020 study.

Children with ADHD were asked to perform a visual sustained attention task before and after taking L-theanine. Their results improved significantly after taking the supplement, suggesting that L-theanine may be beneficial in relieving attention deficit symptoms in those with ADHD.

L-Theanine for Schizophrenia

According to research, L-theanine may alleviate symptoms of schizophrenia by inhibiting glutamate transporters in the brain. Excess glutamic acid in the brain has been linked to schizophrenia. Due to the promising link between L-theanine and glutamate reduction, several studies have examined its effects on people with schizophrenia.

2015 study examined the possible effects of this compound on chronic schizophrenia patients. Results show that there was a significant improvement in schizophrenia symptoms and sleep quality in these test subjects.

Another study, published in 2010, looked at the effects of L-theanine on patients with schizophrenia and schizoaffective disorder. Sixty participants diagnosed with these disorders were given 400 mg of L-theanine per day for eight weeks.

Compared with those who were given a placebo, participants who were given L-theanine supplementation showed significant improvements, especially in positive, activation, and anxiety symptoms.

Cognitive Performance Benefits of L-Theanine

L-theanine can improve cognitive performance, with the combined effects of theanine and caffeine on cognitive functions being particularly beneficial. Combinations of L-theanine and caffeine and their effects on brain activity were researched in a 2010 study.

According to this study, though there was no increase in reaction times in participants after taking the supplement, caffeine and theanine significantly improved subjective alertness in participants.

L-Theanine for Sleep Support

According to the Sleep Foundation, L-theanine is one of the best supplements to take for improving sleep quality and alleviating sleep apnea and other sleep disorders. A study published in 2019 seems to confirm these findings.

This study examined the effects of a GABA and L-theanine mixture on sleep latency (time needed to fall asleep) and sleep quality. The results show that this mixture significantly decreased sleep latency, increased sleep duration, and improved sleep quality (NREM sleep quality, in particular).

Relaxing Properties of L-Theanine Promote Healthy Sleep

L-Theanine for Pain Relief

L-theanine appears to reduce chronic nerve pain, at least in animals. A recent animal study looked at the effects of cysteine and L-theanine on oxaliplatin-induced neuropathy in rodents.

After being given 80 mg of L-theanine and 200 mg of cystine per day for two weeks, the rodents showed fewer signs of neuropathic pain.

There is no way to conclude which of these compounds had a more significant effect on pain reduction, so more research is needed to learn more about the pain-relieving properties of L-theanine.

Anticancer Properties of L-Theanine

According to the Memorial Sloan Kettering Cancer Center, L-theanine is one of the best anticancer agents in integrative medicine. Anticancer benefits of L-theanine on cancer were studied in a 2009 clinical trial.

This trial investigated the effects of the compound on the growth of human lung cancer and leukemia cells and found that L-theanine not only significantly suppressed the growth of these cancer cells, but also enhanced the anticancer activity of several anticancer drugs by reducing cancer cell viability and migration.

L-Theanine Side Effects

There are no long-term side effects of L-theanine, but you may experience some short-term discomfort in the first few days of taking it. Some people experience mild headaches, nausea, and digestive issues after taking L-theanine for the first time, but these side effects subside after a few days.

L-Theanine Drug Interactions

L-theanine may interact with some drugs. Due to its antihypertensive properties, this compound can interact with medications that have the same effect. In the same way, L-theanine's ability to calm anxiety may cause it to interact with sedatives, so make sure to consult a healthcare professional if you want to take matcha and are on anti-anxiety drugs.

Can I Take L-Theanine and Caffeine Together?

Yes, you can take caffeine and L-theanine together. The effects of caffeine and L-theanine are complementary, so it can be incredibly beneficial to take them together. For example, the results of a study published in 2013 suggest that the combination of L-theanine and caffeine improves cognition and mood.

Is it Safe to Take L-Theanine Every Day?

Yes, it is safe to take L-theanine every day, so long as you stick with the recommended daily dose. You will reap more benefits from this adaptogen by taking it every day than if you were to take it occasionally. 

Can Too Much L-Theanine Be Bad?

There are no studies that show any serious side effects of taking too much L-theanine. However, you should not exceed the dose of 200-400 mg per day, especially if you’re new to this compound, as it can cause digestive discomfort and headaches at high doses.

Are You Interested in Taking L-Theanine?

If you’re looking for a supplement with high-quality L-theanine, we've got you covered. Our matcha and cordyceps blend, which comes in two sizes—a 10-serving mushroom matcha box, and a mushroom matcha jar that contains 30 servings—is a functional food with matcha and cordyceps. It contains L-theanine, cordycepin, adenosine, beta-glucans, and many other powerful compounds.

Hone Compostable Mushroom Matcha Packets

Family-Sourced, Ceremonial Grade Matcha

Our matcha comes from an eco-friendly, carbon-neutral family farm in Japan's Shizuoka Prefecture, where matcha has been farmed for generations. This proud farm produces some of the best matcha in the industry and has a strong handmade tradition.

We use "ceremonial matcha," the highest quality grade available. This means that the leaves are grown in the shadow and picked when their nutritional value is at its peak. The process provides you with the best matcha that nature has to offer.

Each serving contains more than 20 mg of L-theanine, which is more than 137 times the quantity found in infused green teas. The silky, refreshing natural flavor is the result of meticulous attention to detail, enthusiasm, and high quality standards. It's no surprise that we're so proud of this matcha.

Premium Cordyceps for Added Benefits

Our blend also contains Cordyceps militaris, an adaptogenic mushroom known for its numerous benefits. The cordyceps mushroom functions as an anti-inflammatory agent, provides energy-boosting properties, and improves general physical and mental well-being.

To learn more about the wonders of this fungus, take a look at our guide to cordyceps mushrooms.

FAQ on L-Theanine

Is L-theanine for energy or sleep?

L-theanine can be used both for energy and for sleep. When combined with caffeine, L-theanine can have incredible energy-boosting properties. On its own, L-theanine is one of the best natural sleep aids and an integral part of a well-maintained sleep hygiene.

Who should not take L-theanine?

Pregnant and breastfeeding women should consult a healthcare provider if they want to take L-theanine due to the lack of research on its effects on fetuses and infants. People on certain medications should also be cautious when taking L-theanine, as this compound may interact with sedatives and blood pressure medication.

Does L-theanine increase serotonin?

Yes, L-theanine appears to increase brain serotonin, as well as dopamine and GABA levels in the brain. The effects L-theanine has on these neurotransmitters are likely the cause of its relaxing properties.

Can L-theanine cause brain fog?

No, L-theanine can’t cause brain fog. On the contrary, this compound may reduce symptoms of brain fog, such as delayed reaction time and memory issues, so it’s safe to assume taking L-theanine can only improve brain fog.

Should I take L-theanine as needed, or daily?

It’s best to take L-theanine daily, especially if you’re new to this supplement. Taking L-theanine regularly increases its effectiveness, especially if you are taking it to treat symptoms of a health condition or to prevent an ailment.

How often should you take L-theanine for anxiety?

You should take L-theanine once or twice per day if you are taking it for anxiety. Unlike anti-anxiety medication, L-theanine is not habit-forming, so you can take it to treat anxiety long-term without the risk of drug dependence or withdrawal.

Is L-theanine safe for the liver?

Yes, at recommended doses, L-theanine is safe and can be quite beneficial for the liver. A 2012 animal study examined the effects of L-theanine on liver injuries caused by alcohol. Results show that this compound significantly reduced the liver damage and oxidative stress caused by alcohol consumption. 

What is the optimal L-theanine dose for anxiety?

Research on taking L-theanine for anxiety suggests that a dosage of 200 mg per day is effective at calming anxiety. However, the exact optimal dosage of L-theanine for anxiety will vary from person to person, so it’s best to experiment until you find the ideal dosage for you. 

Is L-theanine safe for kids?

Yes, L-theanine is safe for kids when taken in recommended doses. WebMD recommends up to 400 mg per day, and a 2020 study on the effects of L-theanine on children used 2.5 mg per kg of body weight with no ill effects. L-theanine supplementation may improve symptoms of hyperactivity disorders and sleep issues in kids.

Is there L-theanine in tea?

Yes, L-theanine is one of the most widely-researched tea components. It’s present in green and black teas, and is especially high in matcha. 


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