What is L-Theanine?

What is L-Theanine?

In the pursuit of holistic health, we're constantly looking into and learning more about the solutions Mother Nature has provided. Natural supplements can be a great addition to support physical and mental well-being. L-theanine, an amino acid primarily found in tea leaves and certain mushrooms, has garnered attention for its potential health benefits. L-theanine in included in quite a few of our products, and in this week's blog we explore what it is and the various ways it may contribute to overall health, supported by scientific research.

What is L-Theanine?

L-theanine is an amino acid predominantly present in green and black tea. The unique umami taste of green tea is partially attributed to the presence of L-theanine. Unlike many amino acids that are building blocks for proteins, L-theanine is known for its unique ability to influence brain function. It promotes relaxation and has been studied for its potential impact on mental health and cognitive performance.

Health Benefits of L-Theanine

1. Promotes Relaxation and Reduces Stress:
L-theanine is widely recognized for its calming properties. Research suggests that it can increase the levels of GABA (gamma-aminobutyric acid), serotonin, and dopamine in the brain—neurotransmitters that help regulate emotions, mood, and stress response. This effect can lead to improved relaxation and occasional stress reduction without causing drowsiness.

2. Enhances Mental Focus and Cognitive Performance:
While L-theanine promotes relaxation, it also enhances alertness and cognitive function. Studies have shown that L-theanine can improve attention, reaction time, and working memory, especially when combined with caffeine, as found naturally in tea.

3. Improves Sleep Quality:
Many people experience improved sleep quality with L-theanine supplementation. It promotes relaxation and reduces anxiety, which can help facilitate better sleep. Unlike traditional sleep aids, L-theanine does not cause drowsiness or dependency, making it a safer option for improving sleep.

4. Supports Immune Function:
Emerging research suggests that L-theanine may have a positive impact on the immune system. It has been shown to enhance the activity of T-cells, which play a crucial role in the body's immune response, potentially aiding in better defense against infections.

5. Reduces Symptoms of Premenstrual Syndrome (PMS):
L-theanine's ability to alleviate stress and anxiety can also help reduce the emotional and physical symptoms associated with PMS. By promoting a sense of calm, it may provide relief from mood swings, irritability, and tension during the menstrual cycle.

6. Supports Cardiovascular Health:
Chronic stress is a known risk factor for cardiovascular disease. By promoting relaxation and reducing stress, L-theanine may contribute to better cardiovascular health. Although more research is needed, these effects are promising for heart health.

How to Incorporate L-Theanine into Your Routine

To experience the potential benefits of L-theanine, consider incorporating it into your daily routine. Drinking high-quality green or black tea is a simple and enjoyable way to consume L-theanine. Alternatively, L-theanine supplements are available in various forms. Many of our products include L-theanine. If you're interested in learning more, you might like to check out our Essence of Life, Detox Cleanse Renew, Fulvic Green, and Essensiac. It is always advisable to consult with a healthcare provider to determine whether a supplement is right for you.

L-theanine is a natural supplement with a variety of potential health benefits, from reducing stress and enhancing cognitive performance to supporting immune function and improving sleep quality. Incorporating L-theanine into a holistic health regimen can support overall well-being. Always consult with a healthcare provider before starting any new supplement to ensure it aligns with your health goals and needs. By embracing the calming and revitalizing effects of L-theanine, you can take a significant step towards a balanced and fulfilling state of well-being.



1. Nobre, A. C., Rao, A., & Owen, G. N. (2008). L-theanine, a natural constituent in tea, and its effect on mental state. *Asia Pacific Journal of Clinical Nutrition*, 17 Suppl 1:167-8.

2. Nathan, P. J., Lu, K., Gray, M., & Oliver, C. (2006). The neuropharmacology of L-theanine (N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent. *Journal of Herbal Pharmacotherapy*, 6(2):21-30.

3. Einöther, S. J. L., & Martens, V. E. G. (2013). Acute effects of tea consumption on attention and mood. *American Journal of Clinical Nutrition*, 98(6 Suppl):1700S-1708S.

4. Bryan, J. (2008). Psychological effects of dietary components of tea: caffeine and L-theanine. *Nutrition Reviews*, 66(2):82-90.

5. Lyon, M. R., Kapoor, M. P., & Juneja, L. R. (2011). The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. *Alternative Medicine Review*, 16(4):348-354.

6. Sugiyama, T., Kang, S. M., & Watanabe, N. (2008). L-theanine mobilizes human peripheral CD34+ cells and inhibits the growth of human leukemia cell lines in vitro. *Cytotechnology*, 58(3):207-211.

7. Nagato, Y., Aoi, N., & Utsunomiya, K. (2012). Effects of L-theanine on the release of alpha brain waves in human volunteers. *Journal of the Food Hygienic Society of Japan*, 42(2):103-110.

8. Eschenauer, G., & Sweet, B. V. (2006). Pharmacology and therapeutic uses of theanine. *American Journal of Health-System Pharmacy*, 63(1):26-30.

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DISCLAIMER: This content is not intended to encourage self-diagnosis, and is purely informational in nature. We are not suggesting any of these supplements, herbs, or natural practices be used in place of medicine or as medicinal alternatives. We do suggest you work with your chosen herbalist, physician, and/or mental health professional about how to best integrate any holistic remedies into your well-being practices. The ancient wisdom of holistic remedies includes a complex system requiring guidance from practitioners whose expertise cannot be summarized in just one article. Discuss any questions or doubts directly with a healthcare practitioner.