Summary
L-theanine is an amino acid found primarily in green and black tea and some mushrooms, and is available in pill or tablet form. It is said to help ease anxiety, stress, and reduce insomnia.
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It may also improve mental focus
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, help people sleep more easily and deeply
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, and contribute to feelings of relaxation by reducing resting heart rate.
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Additionally, research suggests that L-theanine could benefit a person’s mental and physical health.
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According to
