L-theanine in tea and supplements may have benefits for stress, brain health, and sleep. Learn more about the benefits of l-theanine in this expert review.
If you’re like the millions of people looking for natural relief for issues like anxiety, stress, insomnia, and brain health, you may have heard of a supplement or compound found in tea called l-theanine. What is l-theanine? L-theanine is a water-soluble, non-protein amino acid found naturally in green and black tea leaves, as well as some varieties of mushrooms. Its leaves Camellia sinensis The plants are used to make green, black and oolong tea and contain moderate amounts of l-theanine. The amount of l-theanine present in tea depends on several variables, including the variety of tea, the geographic region in which it was grown, and when and how it was harvested. However, a cup of green tea usually contains 8-30 mg of l-theanine, while supplement forms of the amino acid are usually sold in doses of 200 mg or 400 mg. L-theanine is not produced by the human body, nor is it an essential nutrient that must be obtained from the diet, but that does not mean that it should not be included in the diet. Although l-theanine is not classified as an essential nutrient, researchers are studying how its supplemental use may provide a number of health benefits, particularly helping with anxiety, stress, insomnia and cognition operation.
Further research is needed to fully understand the full range of effects that l-theanine supplements have on human health. However, it is believed to be associated with an increase in neurotransmitters, brain alpha wave activity, and protecting cells from free radical damage. Study subjects have been reported to have increased levels of serotonin, dopamine, and gamma-aminobutyrate (GABA) in the brain after taking l-theanine, suggesting that l-theanine can increase neurotransmitters. People have also reported feeling more relaxed, calm, and focused after taking l-theanine supplements, which researchers believe may be attributed to an increase in alpha brain wave activity. In addition, l-theanine is known to contain antioxidant properties, which may help protect cells from free radical damage in the body. Although research is ongoing, studies have shown that this supplement can provide a number of benefits, including improved cognitive function, an improved immune system, reduced blood pressure, reduced anxiety, improved mood, and better sleep.
Four benefits of L-Theanine
Research has found the following potential health benefits of consuming l-theanine.
1. Improves Cognitive Function
A study in which people were given a 100 mg l-theanine supplement or a placebo showed that people who received l-theanine made fewer errors on an attention task than the control group. Correlations have also been made between taking l-theanine with caffeine and an even greater increase in concentration and focus.
2. Reduces stress and blood pressure
Researchers have found that moderate doses of l-theanine can lower resting heart rate and help reduce blood pressure spikes in response to stressful situations where people’s blood pressure previously increased. In one study, a 200 mg dose of l-theanine lowered participants’ resting heart rate, which may help reduce stress and promote relaxation.
3. Improves relaxation and sleep
Many people drink green or black tea in the evenings to relax and prepare for a good night’s rest. One of the reasons for tea’s relaxing properties is probably l-theanine. Consuming l-theanine has been shown to slow your resting heart rate, aid in relaxation, and promote deeper, more restful sleep. Researchers from one study observed that doses of 250-400 mg of l-theanine improved sleep in animals and humans.
4. Improves the immune system
Several studies have shown how l-theanine can benefit the immune system. Although more research is needed, studies have linked l-theanine supplementation to a reduction in upper respiratory infections, improvement in intestinal tract inflammation, and, when combined with the antioxidant properties of green tea, to successful flu prevention.
Who Should Take L-Theanine?
What is the dose of l-theanine for anxiety and other benefits? The recommended dosage usually ranges from 200-400 mg per day, but this varies by product and individual, and additional research is needed to determine appropriate dosages. These supplements available in capsule, tablet, soft gel and powder form. you can buy supplements from health food stores, pharmacies and online retailers. As with any supplement, choosing a reputable brand and following the directions is essential. I always recommend proven third-party supplements. The most common seals to look for are NSF certified, BSCG certified, and USP verified. Although L-theanine is generally safe, it could react with some medications and is not suitable for everyone. Therefore, it is also important to talk to your doctor before taking l-theanine supplements, especially if you are pregnant, receiving chemotherapy treatments, or taking blood pressure medications. A safe way to enjoy the anti-anxiety benefits of l-theanine is to sip a cup of green or black tea more often, as is the tradition in many healthy eating patterns, such as the Japanese diet.
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Written by Anna Tobin, Dietitian with Sharon Palmer, MSFS, RDN
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