Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets
The label defines one serving as two chewable tablets, providing 200 mg of enzymatically produced Suntheanine. The product is vegan and carries Isura non-GMO documentation and mass-spectrometry laboratory verification, but each serving also contains 3 g of added sugar.
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Our Verdict
Its Suntheanine form, 200 mg serving, and named Isura verification are strong on the heavily weighted criteria. It ranks below the winner because of its substantially higher active-ingredient cost and added-sugar chewable formulation.
Score Breakdown
Pros & Cons
Pros
- •200 mg Suntheanine serving directly matches several human-trial doses
- •Isura mass-spec laboratory verification and non-GMO documentation are identified
- •Vegan chewable format with no caffeine
Cons
- •Costs $0.63 per 200 mg serving, the highest cost in this list
- •Two-tablet serving contains 3 g added sugar plus xylitol and flavoring
Specifications
| L-Theanine Per Serving | 200 mg |
| L-Theanine Form | Suntheanine® enzymatically produced L-theanine |
| Serving Size | 2 chewable tablets |
| Servings Per Container | 30 |
| Caffeine | 0 mg; none listed |
| Format / Vegan | Chewable tablets; suitable for vegans |
| Other Ingredients | Organic cane sugar, xylitol, stearic acid, silica, natural tropical flavor, citric acid, magnesium stearate |
| Testing / Certification | Isura non-GMO documentation and mass-spec lab verification; no USP/NSF certificate or downloadable current-lot COA on the page |
Quick Answers
What is the l-theanine per serving of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets l-theanine per serving: 200 mg.
What is the l-theanine form of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets l-theanine form: Suntheanine® enzymatically produced L-theanine.
What is the serving size of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets serving size: 2 chewable tablets.
What is the servings per container of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets servings per container: 30.
What is the caffeine of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets caffeine: 0 mg; none listed.
What is the format / vegan of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets format / vegan: Chewable tablets; suitable for vegans.
What is the other ingredients of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets other ingredients: Organic cane sugar, xylitol, stearic acid, silica, natural tropical flavor, citric acid, magnesium stearate.
What is the testing / certification of the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets?
Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets testing / certification: Isura non-GMO documentation and mass-spec lab verification; no USP/NSF certificate or downloadable current-lot COA on the page.
How much does the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets cost?
The Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets lists at $18.87 at iHerb as of August 5, 2026. Prices change often, so the merchant page shows the current figure.
Who is the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets for?
It suits buyers prioritizing Suntheanine and a 200 mg labeled serving, people who prefer chewables over capsules or powder. It is not the right pick for buyers avoiding added sugar or xylitol, value-focused buyers seeking a low cost per active milligram.
Is the Natural Factors, Stress-Relax, Suntheanine L-Theanine, 100 mg, 60 Chewable Tablets worth buying?
The label defines one serving as two chewable tablets, providing 200 mg of enzymatically produced Suntheanine. The product is vegan and carries Isura non-GMO documentation and mass-spectrometry laboratory verification, but each serving also contains 3 g of added sugar. It ranks #2 in our Top 5 L-Theanine for Calm Focus. Its Suntheanine form, 200 mg serving, and named Isura verification are strong on the heavily weighted criteria. It ranks below the winner because of its substantially higher active-ingredient cost and added-sugar chewable formulation.
Who Is This For?
Best For
- Buyers prioritizing Suntheanine and a 200 mg labeled serving
- People who prefer chewables over capsules or powder
Not For
- Buyers avoiding added sugar or xylitol
- Value-focused buyers seeking a low cost per active milligram
Where to Buy
Appears In
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Customer Reviews
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