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L-theanine is a non-essential amino acid that is found in tea leaves — particularly black tea and green tea — as well as in Bay Bolete mushrooms. It's considered "non-essential" because, despite its benefits to the mind and body, L-theanine is not necessarily needed.

L-theanine can also be obtained through supplement form in addition to food products.

This amino acid affects nerve impulses in the brain and releases neurotransmitters to induce a sense of sedation because it is a natural anxiolytic.

Studies suggest¹ that L-theanine can help promote a sense of relaxation without causing drowsiness. In fact, the biggest reason why people take L-theanine is to help alleviate stress and achieve a state of tranquility.

Benefits of L-Theanine

L-theanine offers a varitey of health benefits, including the following.

Alleviates Stress and Anxiety

While L-theanine has plenty of health benefits, perhaps the biggest and most-well known perk of taking this amino acid is its ability to promote relaxation. Its sedative properties help to put a person at ease and reduce feelings of stress and anxiety.

The great thing about using L-theanine for anxiety is that it is able to increase relaxation without actually making the person feel overly tired. As such, it should not impact a person's ability to continue with regular daily activities.

That said, L-theanine may not be as effective for those who suffer from severe anxiety.

Increases Focus and Attention

While L-theanine may help to relax a person, it can also help to boost attention and mental clarity when taken alongside caffeine. When taken together, both L-theanine and caffeine can improve a person's level of cognition and attention without causing the "jitters."

One study² showed that taking L-theanine and caffeine together helped study participants experience better focus while performing demanding tasks.

To achieve the best effect, proper dosing is required. In this case, taking anywhere between 100-200mg of both L-theanine and caffeine offers the best results.

May Improve Memory

In addition to boosting mental clarity, L-theanine may also be effective in helping to improve long-term memory. One study³ found that patients who suffered from mild cognitive impairment experienced an improvement in recognition skills after taking 60mg of theanine along with green tea extract three times a day for 16 weeks.

Researchers suggest that L-theanine's role in cognitive repair and memory improvement³ is through the prevention of excessive glutamate stimulation of cells in the brain, which may be associated with neurodegenerative disorders and schizophrenia. Blocking glutamate effects may help L-theanine protect the brain, especially as it ages.

Promotes Better Sleep

Since L-theanine is able to induce a sense of relaxation, it only makes sense that it would be able to promote better sleep. The amino acid is also able to reduce resting heart rate, which also helps to relax a person and create the ideal environment in which to fall and stay asleep.

One study4 assessed the effects of L-theanine on a group of children and found that the group who took L-theanine was able to experience longer periods of quality sleep compared to the group who took a placebo. L-theanine may also help to improve quality of sleep in those who suffer from hyperactivity such as ADHD.

May Help Regulate Blood Pressure

L-theanine may be helpful for those who experience an elevation in blood pressure after particularly stressful situations. One study found that L-theanine was able to control higher blood pressure5 after specific stressful mental tasks.

May Help Boost Immunity

Studies suggest that L-theanine may help the body ward off common ailments thanks to a strengthened immune system6. Further, its anti-inflammatory properties may also play a role in combating illness.

How to Use L-Theanine

L-theanine is most effective when taken in supplement form and can be easily consumed through tablets or capsules.

Recommended Dosage

There currently aren't any official guidelines in terms of the amount of L-theanine that can be safely taken. That said, 200mg per day is said to be a safe yet effective amount. In fact, many supplements come already dosed at 200mg per tablet. It's important to follow the directions of manufacturers when dosing L-theanine and speak with a physician first.

Supplementing With L-Theanine

According to the US Food and Drug Administration (FDA), L-theanine is classified as generally safe. However, there may be certain side effects associated with consuming too much of the amino acid, especially when combined with too many caffeinated beverages:

  • Nausea
  • Stomach upset
  • Irritability
  • Interactions with cancer-treating drugs

Further, women who are pregnant or nursing should not use L-theanine, or at least significantly limit the amount of black or green tea they drink. As always, it's best to consult with a physician before taking supplements like L-theanine.

Symptoms of L-Theanine Deficiency

While there are no direct symptoms of a deficiency of L-theanine, there are deficiency symptoms in those who are low in GABA, or Gamma-aminobutyric acid, the brain’s main inhibitory neurotransmitter that prevents overstimulation and promotes a sense of calm.

Supplementing with L-theanine, among other substances, may help alleviate GABA deficiency symptoms7 by boosting GABA function.

Those who are deficient in GABA may experience the following symptoms:

  • Depression
  • Anxiety
  • Panic disorders
  • Drug and alcohol dependence

Is L-Theanine Healthy?

Those who suffer from insomnia, stress, and anxiety may find supplementing with L-theanine helpful. This amino acid has been shown to help promote a sense of relaxation and can even help to improve mental clarity and focus. Be sure to talk to your healthcare provider regarding supplementing with L-theanine and ensure adequate dosage to achieve the desired effects without the side effects.

L-Theanine Supplementation With Total Sleep and Testro-X

There are always certain instances where diet is not going to give you everything you need. There's no need to worry if your diet does not provide the necessary amount of L-theanine. Oral supplements are available for those who want to make sure they are consuming enough in their daily diet.

Total Sleep and Testro-X are powerful, all-natural supplements that contains clinically-proven dosages of L-theanine and other herbs and nutrients. Total Sleep is specially designed to help you sleep naturally. Testro-X is engineered to restore balance to your hormonal ecosystem and optimize the endocrine system for testosterone production. Learn more about Total Sleep, Testro-X and UMZU's line of natural supplements by visiting our online showroom.

With crazy, busy schedules it is easy to be tempted by fast food, processed food, and an abundance of poor eating choices. With obesity and bad eating habits on the rise, it's more important now than ever to pay attention to what you put in your body. Your health is one of the most important investments you can make. After all, you will need it for years to come! Take care to make sure you are receiving adequate amounts of both macronutrients and micronutrients, as well as engaging in healthy exercise. Begin your journey to a healthier you today!

Citations and Source:

1 Nutrients, "Anti-Stress, Behavioural and Magnetoencephalography Effects of an l-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial"

2 Nutritional Neuroscience, "Acute effects of theanine, caffeine and theanine-caffeine combination on attention."

3 Journal of Medicinal Food, "A Combination of Green Tea Extract and l-Theanine Improves Memory
and Attention in Subjects with Mild Cognitive Impairment: A Double-Blind Placebo-Controlled Study"

4 Journal of Child and Adolescent Psychopharmacology, "To Sleep or Not To Sleep: A Systematic Review of the Literature of Pharmacological Treatments of Insomnia in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder"

5 Nutrients, "Anti-Stress, Behavioural and Magnetoencephalography Effects of an l-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial"

6 Beverages, "L-Theanine as a Functional Food Additive: Its Role in Disease Prevention and Health Promotion"

7 University Health News, "4 GABA Deficiency Symptoms You Can Identify Yourself"

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