Here's What You Need To Know About L-Theanine

If you deal with daily stress or trouble sleeping, you&#;ve probably turned to a hot cup of tea to settle your nerves. Indeed, there&#;s good reason tea has a reputation for being so comforting. Research shows that tea can help with everything from lowering cholesterol to improving gut health.

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So, it&#;s natural to think about the ingredients in tea that make it so beneficial. Enter L-theanine &#; an amino acid that&#;s present in tea leaves. It&#;s also used as a supplement, as it may help with anxiety and sleep conditions.

Dietitian Julia Zumpano, RD, LD, talks about what l-theanine is and what you should know before you consider taking it.

What is L-theanine?

L-theanine is an amino acid found in tea leaves, particularly green tea and loose-leaf tea, that has several potential health benefits. But first, let&#;s go over what amino acids are and why they&#;re important.

&#;Amino acids are proteins and they&#;re really the building blocks of our life,&#; explains Zumpano. &#;Amino acids are molecules used by all living things to make proteins. In total, we as humans need 20 different amino acids to function properly. But there are those 11 essential amino acids that our body really needs to get through food.&#;

While L-theanine isn&#;t essential for our survival, its presence in plants and fungi has been studied for its possible impact on our brain function.

L-theanine can be taken by drinking certain teas like green teas, white teas or matcha. It can also be taken as a tablet or pill form.

Benefits of L-theanine

But if you&#;ve looked up the benefits of L-theanine, you may have started to scratch your head. Some proponents claim it can help you feel more alert, while others say that it can help with insomnia. So, which is it? As Zumpano points out, the best way to get the most use out of L-theanine has a lot to do with when you&#;re taking it and what you&#;re pairing it with.

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It&#;s also important to know that these effects may vary from person to person and that there&#;s still limited research on the benefits of taking L-theanine to help with mental and cognitive issues.

Here are some of the explored benefits of L-theanine:

Improving sleep quality

You may have heard that taking L-theanine before bed can help if you experience disruptive sleep or have trouble falling asleep. A study explored the benefits of an L-theanine and GABA supplement combination on sleep quality and length. GABA, short for gamma-aminobutyric acid, is a naturally occurring chemical messenger in your brain that&#;s been linked to creating a calming effect. It&#;s also available as a dietary supplement. The study showed that this combination could potentially increase sleep duration and REM sleep.

According to Zumpano, if you&#;re looking to try L-theanine in tea or supplement form, it&#;s a good idea to take it in the evening before going to bed and not pair it with any coffee or caffeinated beverage. If you&#;re experiencing more serious sleep issues like insomnia or sleep apnea, L-theanine likely won&#;t do the trick.

Also, you should ask your healthcare provider before pairing any prescription medications with L-theanine before bed. L-theanine can be safely taken with melatonin, however.

Reducing stress and anxiety

Remember how a cup of tea can calm you down after a hectic day? Research shows that L-theanine supplements can elevate your levels of GABA, dopamine and serotonin, which promotes relaxation and reduces anxiety levels.

A randomized trial from found that healthy adults who took L-theanine over the course of four weeks had a decrease in stress-related symptoms. While these results are promising, it&#;s important to remember that stress reduction will look different for everyone, depending on what stress response you&#;re having and when you&#;re experiencing it.

Boosting mental clarity

If you&#;re feeling brain fog or a general blah feeling, L-theanine may be able to help give you a boost of mental clarity and enhance your ability to focus. According to the same study, L-theanine helped healthy adults with verbal fluency and the ability to stay focused. The benefits are heightened when taken with caffeine.

&#;If you&#;re going to take L-theanine to gain more alertness and mental clarity, you should take it during the day,&#; advises Zumpano. &#;It does seem to do better with coffee or a caffeinated beverage.&#;

Side effects and risks

L-theanine is generally considered safe and well-tolerated when taken at appropriate doses. In general, it&#;s recommended that you don&#;t exceed 500 milligrams (mg) a day. Most healthy adults can take between 200 mg and 500 mg a day.

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But like any supplement, it may cause side effects, particularly at high doses. You can also simply try upping your tea intake to help get a good dose of L-theanine.

&#;If you&#;re trying to get your L-theanine in the form of black tea or green tea, then you&#;re going to have similar side effects like having too much caffeine,&#; notes Zumpano.

Some of the reported side effects of L-theanine include:

• Headaches.
• Dizziness.
• Nausea.
• Jitteriness.
• Irritability.
• Diarrhea.

Is it safe?

It&#;s important to add that these L-theanine side effects are relatively uncommon and tend to be mild. L-theanine is generally considered safe for most people, but it&#;s always a good idea to talk to your healthcare provider before taking any new supplement, especially if you have any underlying health conditions or are taking medications. In addition, pregnant or breastfeeding (chestfeeding) people should also exercise caution when taking L-theanine, as there&#;s limited research on its safety in these populations.

&#;As of right now, the FDA has classified L-theanine as generally safe, but we don&#;t have specific guidelines on how to take it, just what the studies have shown,&#; adds Zumpano.

It&#;s also important to know that, like all supplements, the U.S. Food and Drug Administration (FDA) doesn&#;t review or regulate L-theanine products. This means no one checks what&#;s sold to ensure it&#;s safe and effective. If you&#;re planning to try L-theanine in supplement form, you should look for a high-quality version with no added fillers.

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If you want to learn more, please visit our website L-Theanine for Nootropic.

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It&#;s said to help ease anxiety, stress, and reduce insomnia. Before trying it out yourself, learn more about the potential health benefits, as well as any possible risks or complications.

L-theanine is an amino acid found primarily in green and black tea and some mushrooms. It&#;s also available in pill or tablet form.

Most known for helping people relax, L-theanine has other potential health benefits, including:

Anxiety and stress relief

Sipping on a hot cup of tea can help you feel at ease, and research suggests that it not only relaxes the mind, but it also does so without causing drowsiness (1).

In a review of five randomized controlled trials that included 104 participants, four trials linked L-theanine with reduced stress and anxiety in people experiencing stressful situations (2).

Another study published in the Journal of Clinical Psychiatry focused on people living with schizophrenia or schizoaffective disorder. Researchers found that L-theanine decreased anxiety and improved symptoms (3).

Increased focus

Paired with caffeine, L-theanine may help increase focus and attention.

A small study found that a combination of L-theanine (97 milligrams, or mg) and caffeine (40 mg) helped a group of young adults focus better during demanding tasks. A typical cup of coffee contains 95 mg of caffeine (4, 5).

The study&#;s participants also felt more alert and less tired in general.

Better immunity

Some research suggests that L-theanine may improve the function of the body&#;s immune system. One study published in the journal Beverages found that L-theanine could help decrease upper respiratory tract infections (6).

Another one found that green tea catechins&#; antioxidants&#; and theanine could be effective at preventing the flu (7, 8).

Another study found that L-theanine could help improve inflammation in the intestinal tract. However, more research is needed to confirm and expand on these findings (6, 9).

Tumor and cancer treatment

L-theanine has also been associated with amplifying the anti-tumor effects of certain chemotherapy drugs. Because of these promising findings, researchers expect that L-theanine could also help improve chemotherapy&#;s ability to fight cancer (10).

Although there&#;s no definitive evidence to show that tea prevents cancer, a number of studies suggest that people who regularly drink tea have lower rates of cancer (10, 11, 12).

Researchers of one study in China found that women diagnosed with ovarian cancer who drank at least one cup of green tea a day lived longer than those who didn&#;t (13).

Another study that looked at tea drinkers compared to nondrinkers found that women who drank green tea were 32 percent less likely to develop pancreatic cancer (14).

Blood pressure management

L-theanine may be beneficial for those who experience increased blood pressure in stressful situations.

One study found that people who usually experienced higher blood pressure after specific mental tasks found that L-theanine helped reduce an increase in blood pressure.

In the same study, the researchers noted that caffeine had a similar but less beneficial effect (15).

Some research indicates that L-theanine could be beneficial for a good night&#;s sleep, which could be because it helps to promote relaxation.

Researchers in one study found that doses of 250 mg and 400 mg of L-theanine greatly improved sleep in animals and humans (16).

Also, 200 mg of L-theanine was shown to help reduce resting heart rate, pointing to its ability to promote relaxation (16).

L-theanine may also help boys diagnosed with attention deficit hyperactivity disorder (ADHD) sleep better.

A double-blind study looked at the effects of L-theanine on 98 boys ages 8 to 12 years old. A randomized group was given two 100 mg chewable tablets of L-theanine twice daily. The other group received placebo pills.

After 6 weeks, the group taking L-theanine had longer, more restful sleep. While the results are promising, more research is needed before it can be proven safe and effective, especially for children (17).

Other research suggests that L-theanine improved sleep quality for those diagnosed with schizophrenia (18).

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