L-Theanine Explained: Supporting Calmness & Mind Relaxation
If you're feeling overwhelmed by the pressures of work, family responsibilities, or simply the demands of everyday modern life, then it’s natural to look for ways to keep yourself calm and feel more under control. Things like deep breathing, having time out, exercise and getting plenty of sleep can all help. But there may be another way to help calm the mind through the unique amino acid L-theanine.
What is L-theanine?
If you've ever felt that sitting down to a cup of tea can be a calming experience, you can thank L-theanine for helping with that experience. L-theanine is a naturally occurring amino acid found in tea leaves so you will consume it every time you drink black or green tea.
Unlike protein-building amino acids, L-theanine has a different effect on the body. What makes it especially interesting is its ability to cross into the brain. Once in the brain, it can have a calming and stress-reducing effect, while also supporting cognitive function.
How L-theanine helps manage stress
After you consume L-theanine, it can cross the blood-brain barrier and affect brain activity by increasing the activity of alpha waves. Alpha waves are a type of brainwave that are most prominent when a person is awake but in a relaxed, calm and alert state. Think of it as the mental state you experience during a peaceful walk or when you're completely absorbed in a creative activity that you enjoy. These same alpha waves may explain the calming effects of L-theanine.
What is AlphaWave?
L-theanine is found naturally in tea, but it also can be taken in a supplement form called AlphaWave®. This form of L-theanine is standardised to contain a specific and highly purified amount of L-theanine.
The benefits of taking L-theanine
Several clinical studies have confirmed the ability of AlphaWave® L-theanine to increase alpha brainwave activity and convey significant relaxation benefits. 1, 2
In the first of the clinical trials published in 2021, 16 healthy adults with moderate levels of stress took a single 200 mg dose of AlphaWave® L-Theanine or a placebo. When taking the AlphaWave® L-Theanine, there was a significant increase in alpha brain wave activity. This change in alpha brain wave activity was linked to lower levels of stress and less mild anxiety when faced people were faced with a challenging mental tasks.1
A second clinical trial involving 30 healthy adults who took 400 mg of AlphaWave® L-theanine for 28 days or a placebo was published in 2024. Similar to the first trial, people who took AlphaWave® experienced significantly less perceived stress while at the same time also reporting better cognitive attention.2
So beyond helping you feel calmer, L-theanine offers other benefits where it may support mental and cognitive function, helping you think more clearly even when life gets demanding.2
Understanding the different doses of L-theanine
The amount of L-theanine that works best can vary depending on your individual needs and what you're hoping to achieve. Common doses used in clinical trials range from 100 mg up to 400 mg daily.
For general support in managing everyday pressures, a dose of 200 mg per day has shown promising results in promoting a calming response.1 For people who need additional support, a higher dose of up 400 mg daily has also shown benefits in managing stress and helping to assist cognitive function.2
Making it work for you
Whether you're facing a particularly demanding week at work or simply want to support your overall sense of calm and focus, consuming L-theanine from tea or in a supplement form is an option worth considering.
Consult your healthcare professional before starting L-theanine supplements, especially if you're taking other medications or have existing health concerns.
References
1. Evans et al. A randomized, triple-blind, placebo-controlled, crossover study to investigate the efficacy of a single dose of AlphaWave® L-theanine on stress in a healthy adult population. Neurology and Therapy 2021;12:1061-1078. https://link.springer.com/article/10.1007/s40120-021-00284-x
2. Moulin M et al. Safety and efficacy of AlphaWave® L-theanine supplementation for 28 days in healthy adults with moderate stress: a randomized, double-blind, placebo-controlled trial. Neurology and Therapy 2024;13:1135-1153. https://link.springer.com/article/10.1007/s40120-024-00624-7
®AlphaWave is a registered trademark of Ethical Naturals.