Background

• Theanine is an amino acid found naturally in tea. Besides caffeine, theanine has been identified as a major component of tea. While younger and fresher tea leaves tend to be richer in caffeine, older leaves tend to have higher theanine levels; furthermore, the withering process of tea production also increases theanine content.
• Some evidence suggests that theanine affects mental performance and reduces blood pressure. Research has examined the cognitive effects of this substance alone and when combined with caffeine.

References

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