L-theanine improves subjective sleep quality and reduces anxiety without causing drowsiness
L-theanine (200mg daily) improves subjective sleep quality and reduces anxiety in adults with high anxiety levels. Unlike many sleep aids, it does not cause daytime drowsiness and promotes relaxation via alpha-wave enhancement.
Evidence Score
Mechanism Graph
Limitations
- ⚠Small sample size (n=12 in primary RCT)
- ⚠Subjective measures only (no PSG)
- ⚠Limited to high-anxiety population
- ⚠No dose-response data
Frequently Asked Questions
Does L-theanine help with sleep?▼
L-theanine (200mg) improves subjective sleep quality and reduces anxiety. It promotes relaxation without sedation, making it suitable for daytime use as well.
Can I take L-theanine every day?▼
L-theanine is safe for daily use. No adverse effects have been reported at doses up to 400mg/day in studies.
Should I take L-theanine with caffeine?▼
L-theanine is commonly paired with caffeine to promote calm alertness. For sleep, take it alone 30-60 minutes before bed.
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