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.
We may earn a commission when you buy through our links.
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 |
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
Customer Reviews
Alternatives to Consider
California Gold Nutrition, L-Theanine, Featuring AlphaWave, 100 mg, 60 Veggie Capsules
California Gold Nutrition
Each vegan capsule supplies 100 mg of branded AlphaWave L-theanine without caffeine. A published iTested report identifies the product codes, laboratories, potency result, and microbial results, although it covers lot 3533 from 2018 rather than current inventory.
Doctor's Best, L-Theanine, AlphaWave, 200 mg, 60 Veggie Caps
Doctor's Best
One vegan capsule supplies 200 mg of AlphaWave L-theanine with no caffeine. The label fully discloses the active dose and excipients, but the iHerb page does not link a recognized finished-product certification or product-specific certificate of analysis.
Nutricost, L-Theanine, Unflavored, 3.6 oz (100 g)
Nutricost
Each 0.2 g scoop contains 200 mg of generic L-theanine, and the label lists no other ingredients. It is by far the lowest-cost option per active milligram, although the page supplies only a general third-party-tested claim rather than a named certification or published COA.
EVLution Nutrition, L-Theanine, 200 mg, 60 Veggie Capsules
EVLution Nutrition
Each vegan capsule supplies 200 mg of generic L-theanine without caffeine. It provides strong active-ingredient value and a trial-aligned dose, but the label does not identify a branded purity process, recognized certification, or product-specific COA.