XYMOGEN L-Theanine, 120 Vegetarian Capsules supplement bottle
XYMOGEN

L-Theanine, 120 Vegetarian Capsules Review

What We Researched
1 active ingredient analyzed · 5 inactive ingredients decoded · 7 brand certifications checked · Last updated: Aug 2026
100
Product Score Excellent
100
Brand Score Excellent

Two independent scores — the product and the brand behind it, never blended into one number. See our methodology.

Product Analysis

Transparency Excellent

Supplement Facts

IngredientAmount% DV
L-Theanine 400 mg *
Bioavailability Excellent

Absorption Rating

  • L-Theanine Good
Other Ingredients Excellent

Fillers & Additives

  • Hypromellose
  • Microcrystalline Cellulose
  • Ascorbyl Palmitate
  • Water
  • Medium-chain Triglycerides Oil
Efficacy Excellent

Dosage Analysis

  • L-Theanine 400 mg Effective

Supplement Facts

Ingredient Amount % Daily Value
L-Theanine 400 mg *

Other Ingredients

Inactive ingredients used in manufacturing. All rated for safety.

Hypromellose Safe

Forms vegetarian capsule shells. Dissolves easily in the stomach.

Microcrystalline Cellulose Safe

Adds bulk to small-dose supplements to make tablets/capsules a manageable size.

Ascorbyl Palmitate Safe

Prevents oxidation and extends shelf life of oil-based supplements.

Water Safe

Dissolves and carries water-soluble ingredients.

Medium-chain Triglycerides Oil Unknown
Brand Trust Report
XYMOGEN

Founded 2003 · Orlando, Florida, United States · 398 products · xymogen.com/

Certifications

7 certifications
Consumerlab Verified Source
Nsf Certified For Sport Verified Source
Fda Gmp Inspections Verified Source
Nsf Gmp Verified Source
NSF Certified for Sport Verified
NSF Contents Certified Verified
NSF Certified Verified

Transparency

6 claims
Third Party Testing Claim — Verified Source
Coa Availability — Verified Source
Testing Lab Disclosure — Verified Source
In House Testing — Verified Source
Contains Proprietary Blend — True

Violation History

1 incident
Fda Warning The warning letter cited violations of current Good Manufacturing Practice (cGMP) regulations for dietary supplements, including failure to establish product specifications for the identity, purity, strength, and composition of the finished dietary supplement, and failure to conduct at least one appropriate test or examination to verify the identity of a dietary ingredient. The letter also noted that several products were considered new drugs because they were not generally recognized as safe and effective for their intended use.2011-12-13Source
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Frequently Asked Questions
Is XYMOGEN L-Theanine, 120 Vegetarian Capsules a good supplement?

XYMOGEN L-Theanine, 120 Vegetarian Capsules received a product quality score of 100/100 in GoodSupp's independent analysis, placing it in the top tier of supplements we've analyzed. The product contains 1 active ingredients with 60 servings per container. Of the 5 inactive ingredients, 4 are rated safe and 0 are flagged for review. The manufacturer, XYMOGEN, holds a brand trust score of 100/100 with 7 verified certifications including Consumerlab, Nsf Certified For Sport, Fda Gmp Inspections, Nsf Gmp.

What are the ingredients in XYMOGEN L-Theanine, 120 Vegetarian Capsules?

XYMOGEN L-Theanine, 120 Vegetarian Capsules contains 1 active ingredients: L-Theanine (400 mg). Each ingredient's dosage, form, and safety rating is analyzed independently in GoodSupp's full product breakdown.

Is XYMOGEN L-Theanine, 120 Vegetarian Capsules safe to take?

XYMOGEN L-Theanine, 120 Vegetarian Capsules has been analyzed for ingredient safety across all its components. Always consult your healthcare provider before starting any new supplement, especially if you take medications or have underlying health conditions.

Is XYMOGEN a trustworthy supplement brand?

XYMOGEN receives a brand trust score of 100/100 based on GoodSupp's independent analysis of certifications, regulatory history, and transparency practices. Founded in 2003 and headquartered in Orlando, Florida, United States, the company offers 398 products in their lineup. They hold 7 verified certifications including Consumerlab, Nsf Certified For Sport, Fda Gmp Inspections, Nsf Gmp. Third-party certifications are independently verified and indicate the brand meets specific quality, purity, and manufacturing standards. Note: XYMOGEN has 1 historical regulatory incident on record, which are factored into the trust score.

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Disclaimer: GoodSupp provides independent supplement quality analysis for informational purposes only. Scores are generated algorithmically based on ingredient profiles, brand certifications, and public records — read our methodology. This is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Product data is sourced from manufacturer labels and public databases. GoodSupp is not affiliated with any supplement brand.