L-Theanine
Amino acid found in tea that promotes relaxation without drowsiness.
How it works
Mechanism of Action
L-Theanine increases alpha brain wave activity and boosts GABA, serotonin, and dopamine levels, promoting calm focus.
Evidence-based uses
What L-Theanine Is Used For
Works well combined with magnesium. Promotes relaxation without sedation.
Clinical Evidence
Systematic review of 9 studies found 200-400mg L-theanine improved sleep quality, reduced sleep latency, and enhanced next-day alertness without sedation in adults with stress-related sleep issues.
L-theanine (200mg daily) significantly decreased sleep latency, reduced sleep disturbance scores, and increased sleep quality compared to placebo in adults with generalised anxiety.
Can be taken as needed for acute stress. Works within 30-60 minutes.
Clinical Evidence
RCT found 200mg L-theanine significantly reduced salivary cortisol and subjective stress responses to an acute stressor compared to placebo, with effects within 1 hour of ingestion.
Promotes calm focus. Works well with caffeine. Fast-acting.
Clinical Evidence
Crossover RCT found 200mg L-theanine improved attention and reaction time during demanding cognitive tasks, with effects observed within 1-2 hours of ingestion.
Safety
Interactions & Warnings
L-Theanine may have mild blood pressure lowering effects, potentially enhancing antihypertensive medications. Generally considered safe but monitor.
Compare prices
Buy L-Theanine in Australia
6 products compared across Australian retailers. Sorted by price per serve.
| Product | Price | /serve | |
|---|---|---|---|
Best NOW Foods L-Theanine 200 mg, 120 Veg Capsules iHerb | $17.99 | $0.15 | Buy |
NOW Foods NOW Foods L-Theanine 200mg 120 Veg Caps Amazon AU | $34.95 | $0.29 | Buy |
Nature's Own L-Theanine 200mg 60 Capsules Chemist Warehouse | $19.99 | $0.33 | Buy |
Nature's Own Nature's Own Stress & Sleep 60 Tabs Chemist Warehouse | $24.99 | $0.42 | Buy |
Thorne Thorne Theanine 200mg 90 Caps iHerb | $42.00 | $0.47 | Buy |
Thorne PharmaGABA-250, 60 Capsules Thorne | $54.99 | $0.92 | Buy |
Prices in AUD. Some links are affiliate links — we may earn a commission at no extra cost to you.
Should you take L-Theanine?
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This information is for educational purposes only and is not intended as medical advice. Always consult a healthcare professional before starting any supplement. Evidence ratings are based on peer-reviewed clinical research. Individual results may vary.