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.
This article is automatically generated from the structured evidence profile behind the claim above. Scores reflect the quality and quantity of available research, not clinical advice.
L-theanine improves subjective sleep quality and reduces anxiety without causing drowsiness The current body of evidence comprises 1 study, including 1 randomized controlled trial. EvidenceHub rates the overall confidence at 73/100 (moderate).
The Claim
L-theanine improves subjective sleep quality and reduces anxiety without causing drowsiness
This conclusion is most relevant to: Adults with high anxiety, Adults with mild sleep complaints.
How It Works
The proposed biological pathway:
- ▸L-Theanine
- ▸Glutamate receptor modulation (AMPA/kainate)
- ▸GABA and glycine neurotransmitter enhancement
- ▸Increased alpha brain wave activity
- ▸Reduced anxiety and physiological stress
- ▸Improved subjective sleep quality
Who Might Benefit
Evidence fit by population:
- ▸Adults with high anxiety
- ▸Adults with mild sleep complaints
Recommended Dose
200mg
Limitations & Caveats
Important context when interpreting this evidence:
- ▸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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