The original, most clinically researched L-theanine. Clinically proven to support calm, focus, and restful sleep without drowsiness. Backed by 50+ Suntheanine®-specific studies and 30+ years of trust for quality, consistency, and predictable results. Suntheanine® is produced through a patented enzymatic fermentation process that mirrors how L-theanine forms naturally, delivering a clinically meaningful dose with unmatched purity and fast-acting calm you can feel. If you've tried generic L-theanine, prepare for a real upgrade.
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Suggested Use: Take 1 capsule daily with water, or as directed by your healthcare practitioner. Relevant for: Stress management, work, study, performance and everyday mental balance.
Recommendations: Adults, as a dietary supplement, take once or twice daily.
Supplement Facts
Serving Size: 1 CapsuleServings per Container: 60
Amount per Serving
% Daily Value
Suntheanine® L-Theanine
200 mg
†
†Daily Value not established
Other Ingredients: Vegetable Cellulose, Rice Extract.
Contains No: Artificial Sweeteners, Dairy, Wheat or Yeast.
Do not use if safety seal is broken or missing. Store in a cool, dry place.
Suntheanine® is a trademark of Taiyo International, Inc.
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Suntheanine® 200 mg
$25.00
Why You’ll Love Suntheanine®?
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Improves focus*
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Reduces stress*
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Improves sleep*
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Calm focus from your first dose*
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Feel focused without drowsiness*
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Delivers a state of calm clarity in as little as 30 minutes*
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50+ clinical studies on Suntheanine®
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Enzymatic fermentation purity
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The original nature inspired form of L-theanine
Certifications
What Makes Suntheanine® Different ?
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The original L-theanine
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Bio-identical, mirrors nature
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Made by enzymatic fermentation
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50+ clinical studies
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FDA GRAS confirmed safety
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Consistent, predictable results
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Trusted worldwide for 30+ years
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How Suntheanine® Works
Suntheanine® L-theanine supports a calm, relaxed alertness by influencing the brain's natural alpha wave activity. This is the same brainwave pattern associated with deep focus and mental clarity.
01
Crosses the blood brain barrier efficiently*
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Helps promote focus*
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Improves cognitive performance when combined with caffeine*
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Quickly feel the benefits after your first dose*
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Promotes calm and clarity without grogginess*
For Moments When It Matters Most
When pressure builds, you need to stay clear, composed, and in control.
Calm without losing clarity
Focus without overstimulation
Rest without sedation
What the Experts Say
Shawn Talbott
PhDPsychonutritionistStress affects many areas of your life, from sleep to sports performance to energy levels. Suntheanine® helps you settle into a more positive cycle: sleeping better at night leads to more daytime energy which leads to more quality sleep and continued productive days.
Bryce Wylde
B.Sc. Hons. (BioPsyc), DHMHSFunctional Medicine ExpertSuntheanine® replaces my 2 p.m. cup of coffee, giving me the power of coffee without the jitters. A calm, focused and alert attention is the type of energy we all desire: energy that makes us more efficient, not frazzled and distracted.
Michael R. Lyon
MDPhysician, medical researcher and authorI was in charge of a large double blind study where 200 mg Suntheanine® was consumed twice per day for 6 weeks in 8-12 years boys with ADD. No side effects were reported and I now view Suntheanine® as one of the safest natural products that can be given to a child.
Frequently Asked Questions
How fast does Suntheanine® 200mg work?
Most people feel noticeably calmer and report more focus with their very first dose, often within about 30 minutes.*
Can I take it with caffeine?
Yes, you can take Suntheanine® with caffeine to help smooth out jitteriness while at the same time supporting mental clarity.*
What makes it different from generic L-theanine?
Suntheanine® is clinically researched, patented, nature inspired, and produced via a patented pure enzymatic fermentation.*
Will it make me drowsy?
No. Suntheanine® supports calm and clarity without sedation.*
Is it safe for daily or long-term use?
Suntheanine® has been used safely in numerous clinical trials and is trusted by healthcare practitioners.*
"I've taken other forms of L-theanine in the past, which were 100 mg and did not have noticeable sleep improvement. With Suntheanine and the Journey program, I was able to measure improvements in my sleep quality over a 30-day period and confirmed it works!"
— Mike D. (5/5)
Love the new 200 mg option!
"I've been a fan of the Tomorrow's Nutrition Suntheanine product, but am loving the new double strength 200 mg, especially for improving the quality of sleep."
— James S. (5/5)
"Works very well, definitely will be continuing to order!"
— John (5/5)
I have been able to sleep much better
"I find that when I take this product, I sleep much better throughout the night. I feel better in the morning too; it's been great."