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L-Theanine Reduces Symptoms of Anxiety

An amino acid in green tea helps reduce generalized anxiety.

The amino acid L-theanine is an effective treatment of moderate and severe anxiety and does not cause drowsiness.

Green tea is used as a restorative in traditional Chinese medicine and contains many bioactive constituents, including the amino acid L-theanine. In recent years L-theanine has been extracted from green tea and is now widely used to treat anxiety symptoms and depressed mood in China, Japan, and other Asian countries. The calming effects of L-theanine are believed to compensate for the stimulating effects of caffeine in green tea (Kakuda 2000).

The anti-anxiety effect of L-theanine is achieved through enhanced alpha brain wave activity and increased synthesis of GABA (Juneja 1999; Kakuda 2000). Increased GABA, in turn, increases brain levels of dopamine and serotonin, resulting in general feelings of calm and well-being (Mason 2001).

Changes in brain electrical activity measured by EEG are dose-dependent, and are similar to beneficial EEG changes observed in meditation, including increased alpha waves in the occipital and parietal regions (Ito 1998).

A calming effect is usually noted within 30 to 40 minutes after L-theanine is taken at a dose of 50 to 200mg, and typically lasts 8 to 10 hours. Moderate anxiety symptoms often improve with a regimen of 200mg once or twice daily. More severe anxiety symptoms may require doses up to 600mg to 800mg daily taken in increments of 100mg to 200mg spaced over the day.

Unlike benzodiazepines and other conventional anti-anxiety treatments, L-theanine does not result in increased drowsiness, slowed reflexes, or impaired concentration. There is no risk of developing tolerance or dependence, and there have been no reports of serious adverse side effects or interactions with other natural products or synthetic drugs.

Learn more in my e-book, Anxiety: The Integrative Mental Health Solution.

About the Author
James Lake, MD

James Lake, M.D., a clinical assistant professor at the University of Arizona College of Medicine, works to transform mental health care through the evidence-based uses of alternative therapies.

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