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L-Theanine 200 mg

product on market Tablet or Pill Best Naturals Safety: 100/100
100/100

This product looks safe

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

What the Evidence Says

AI-generated · Qwen 3.6 · grounded in 1 source · methodology

L-theanine is supported by moderate to strong evidence for its ability to promote relaxation and reduce stress without causing sedation. Research indicates it may improve cognitive focus when paired with caffeine. The ingredient profile is generally recognized as safe for most healthy adults.

AI-generated summary based on research evidence. Not medical advice.

Label

Product Label

Label for L-Theanine 200 mg
Open Full PDF View on NIH DSLD →
Details

Label Data

1 Tablet(s)
Serving Size
120
Servings
Non-Nutrient/Non-Botanical
Product Type
100%
Evidence Coverage
Ingredients

Supplement Facts — Evidence Check

200 mg
Market median: 200.0mg (358 products) 9 studies (A:0, B:2)

Other Ingredients

Dicalcium Phosphate Microcrystalline Cellulose Stearic Acid Croscarmellose Sodium Silicon Dioxide Magnesium Stearate Pharmaceutical Glaze
Claims

Label Claims — Verification

Unverified All Other
Unverified Structure/Function
Info

Product Information

Directions for Use

Suggested Use: As a dietary supplement, take one (1) tablet one to two times daily as needed, preferably on empty stomach, or as directed by your qualified healthcare professional.

Warnings & Precautions

Keep out of the reach of children.

Do not use if safety seal is broken or missing.

GMP Good Manufacturing Practice Product

Caution: For adults only, if you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.

Discontinue use and consult your doctor if any adverse reactions occur.

Formulation Notes

L-Theanine is a unique amino acid naturally found in green tea that exerts beneficial effects on brain metabolism. Animal studies have shown that L-theanine crosses the blood brain barrier, increases dopamine and GABA levels in the brain, and inhibits the stimulatory properties of caffeine. L-Theanine promotes relaxation without the drowsiness or negative side effects associated with other calming agents as measured by increased generation of alpha-waves. Certain research publications indicate that L-Theanine may help support the following: Supports healthy cardiovascular system. Supports healthy brain and nervous system. Supports learning ability. Supports relaxation and well-being.

Premium formula

3rd party lab tested

No artificial color, flavor or sweetener, no preservatives, no sugar, no starch, no corn, no soy, no egg, no lactose, no gluten, no wheat, no yeast, no fish. Sodium free.

Additional Information

Keep in cool, dry place.

Made in USA

Metadata

Product Details

UPC / SKU8 17716 01854 6
DSLD Entry Date2022-07-21
Product TypeNon-Nutrient/Non-Botanical
FormTablet or Pill
DSLD ID269823
Data Updated2026-04-11
Research

Research Evidence

37
Research Sources
53
Avg Quality
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
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This product page is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before taking any supplement.