Suntheanine L-Theanine, 60 Tablets
Natural Factors Suntheanine L-Theanine delivers a patented, pure-form L-theanine, the amino acid found naturally in green tea, to support relaxed alertness and a calm mental state without drowsiness.
May be a fit for
- Adults seeking L-theanine to support calm, relaxed focus
- Those using Suntheanine before high-pressure work or presentations
- Individuals supporting restful sleep onset with pure L-theanine
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Natural Factors Suntheanine L-Theanine delivers a patented, pure-form L-theanine, the amino acid found naturally in green tea, to support relaxed alertness and a calm mental state without drowsiness. Suntheanine is produced via a proprietary enzymatic fermentation process that yields a pharmaceutical-grade, 99%+ pure L-theanine isomer, identical to what's found in tea leaves. This formulation is suited for adults seeking to support focus and stress management as part of a daily wellness routine.
Why It's Worth Considering: The Suntheanine trademark represents one of the most rigorously studied forms of L-theanine, with the specific isomer and purity level used in published clinical research on relaxation and cognitive support.
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Product details
Who it may suit
May be a fit for
- Adults seeking L-theanine to support calm, relaxed focus
- Those using Suntheanine before high-pressure work or presentations
- Individuals supporting restful sleep onset with pure L-theanine
- Coffee drinkers looking to maintain alertness while easing jitteriness
Considerations
- Taking blood pressure medications (L-theanine may lower BP)
- Very low blood pressure already
- Generally very safe — one of the best-tolerated supplements
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L-Theanine widely praised for reducing anxiety and mental fog while promoting calm focus without sedation, especially combined with caffeine.
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How fast does L-theanine work?
L-theanine produces measurable alpha brain wave increases within 30-40 minutes of ingestion. Most people notice a sense of calm focus within 30-60 minutes. Unlike prescription anti-anxiety medications, it works quickly without sedation, cognitive impairment, or dependence.
Can I take L-theanine with coffee?
Yes — this is the most well-studied nootropic combination. L-theanine (200mg) smooths caffeine's stimulatory effects, reducing jitteriness and anxiety while preserving alertness and focus. Studies show the combination improves attention and task-switching better than either alone. The ideal ratio is 2:1 theanine to caffeine.
Is L-theanine safe to take every day?
Yes. L-theanine is one of the safest supplements available — it's the primary amino acid in green tea. Doses up to 400mg/day have shown no adverse effects in clinical studies. No tolerance builds up, no withdrawal, and no dependence. It can be taken daily for years without concern.
Does L-theanine help with sleep?
L-theanine improves sleep QUALITY without causing drowsiness — it promotes relaxation and reduces racing thoughts, making it easier to fall asleep. It's particularly effective for people whose insomnia is driven by anxiety or an overactive mind. Take 200-400mg about 1 hour before bed. Unlike melatonin, it won't make you groggy if you need to wake up.
Supplement information is provided for education and is not a substitute for personalized medical advice. Supplements are not intended to diagnose, treat, cure or prevent disease. Read the current product label before use.