L-Theanine 400 mg

product on market Capsule OL Olympian Labs 🟢 Safety: 100/100
Brand: OL Olympian Labs
🟢 100/100

This product looks safe

  • No ingredients exceed tolerable upper intake levels
  • 100% of ingredients have research evidence
A Label Compliance Grade

Product Label

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Label Data

2 Capsule(s) Serving Size
30 Servings
Non-Nutrient/Non-Botanical Product Type
100% Evidence Coverage

Supplement Facts — Evidence Check

400 mg
📊 Market median: 200.0mg (358 products) 📚 9 studies (Tier A: 0, B: 2)
This product: 400mg

Other Ingredients

Vegetarian Capsule Rice Flour Microcrystalline Cellulose Silicon Dioxide Ascorbyl Palmitate

Label Claims — Verification

❓ All Other
❓ Structure/Function
All Other (99% of products) Structure/Function (92% of products) Nutrient (22% of products)

Target Groups

Vegan Vegetarian Adult (18 - 50 Years) No Allergies Gluten Free Dairy Free

Product Information

📋 Directions for Use

Suggested Use: As a dietary supplement, take two (2) capsules daily on an empty stomach, or as directed by a healthcare professional.

⚠️ Warnings & Precautions

Discontinue use if allergic reaction occurs.

Keep out of reach of children.

Caution: If you are pregnant or nursing, have a medical condition, or are taking medication, consult your healthcare professional before using this or any other nutritional supplement.

🧪 Formulation Notes

Non-GMO

Vegan

Gluten free

Allergen free

No: Milk, Eggs, Fish, Crustaceans Shellfish, Tree Nuts, Peanuts, Wheat, or Soybeans.

L-Theanine 400 mg per serving

Allergen free

Additional Information

Helps reduce stress & anxiety

Rev 07-18-16

Mental focus support

Relax without feeling drowsy

30 servings

Made in USA

We do not use ingredients that were produced using modern biotechnology

Pharmaceutical grade

Store in a cool, dry place.

Olympian Labs, Inc. products are made with the highest quality ingredients and manufactured according to current Good Manufacturing Practices (cGMP).

Product Details

UPC / SKU 7 10013 03231 7
DSLD Entry Date 2016-12-23
Product Type Non-Nutrient/Non-Botanical
Form Capsule
Brand OL Olympian Labs
DSLD ID 67068
Data Updated 2026-04-11

Research Evidence

37 Research Sources
53 Avg Quality Score
22 Rct
10 Systematic Review
3 Meta Analysis
1 Clinical Trial
1 Openfda Safety
B Examining the effect of L-theanine on sleep: a systematic review of dietary supplementation trials
Systematic Review Nutritional neuroscience 2026
PubMed DOI
B The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis
Meta Analysis Sleep medicine reviews 2025
PubMed DOI
B The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness
Rct Nutritional neuroscience 2010
PubMed DOI
B Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial
Rct Nutrients 2019
PubMed DOI
B The Role of Supplements and Over-the-Counter Products to Improve Sleep in Children: A Systematic Review
Systematic Review International journal of molecular sciences 2023
PubMed DOI
B Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Meta Analysis Nutrition reviews 2025
PubMed DOI
B Effect of Alpha-S1-Casein Tryptic Hydrolysate and L-Theanine on Poor Sleep Quality: A Double Blind, Randomized Placebo-Controlled Crossover Trial
Rct Nutrients 2022
PubMed DOI
B Effect of L-theanine on selective attention in a traffic-related reaction task in sleep-deprived young adults: a double-blind placebo-controlled, crossover study
Rct Nutritional neuroscience 2025
PubMed DOI
B The combined effects of L-theanine and caffeine on cognitive performance and mood
Rct Nutritional neuroscience 2008
PubMed DOI
B Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a systematic review and meta-analysis
Meta Analysis Nutrition reviews 2014
PubMed DOI
View all evidence for L Theanine →

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