Home/ Supplements/ L Theanine/ L-Theanine

L-Theanine

product on market Capsule Dr. Berg Safety: 90/100
90/100

This product looks safe

  • Contains proprietary blend — exact ingredient amounts not disclosed
  • 60% of ingredients have research evidence
A Label Compliance Grade

What the Evidence Says

✨ AI-generated · Qwen 3.6 · methodology

L-theanine is supported by strong evidence for promoting relaxation and cognitive focus. Zinc, copper, and manganese provide essential mineral support for metabolic and immune functions, though the proprietary blend lacks specific dosing data. Overall evidence coverage for this specific formulation is limited.

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

Alerts

Safety Alerts

Contains proprietary blend — exact ingredient amounts not disclosed

Label

Product Label

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

Label Data

1 Capsule(s)
Serving Size
90
Servings
Other Combinations
Product Type
60%
Evidence Coverage
Ingredients

Supplement Facts — Evidence Check

0.4 mg (4% DV)
Market median: 18.0mg (1009 products) 263 studies (A:6, B:134)
0.03 mg (3% DV)
Market median: 2.0mg (138 products) 37 studies (A:0, B:11)
3 mg (130% DV)
1.3× RDA — within safe limits 9 studies — no high-quality reviews
200 mg
Market median: 200.0mg (358 products) 9 studies (A:0, B:2)
Proprietary Blend
385 mg

Other Ingredients

Gelatin Microcrystalline Cellulose Magnesium Stearate
Claims

Label Claims — Verification

Unverified Nutrient
Unverified All Other
Unverified Structure/Function
Info

Product Information

Directions for Use

Suggested use: As a dietary supplement, take 1 capsule, with meals, 3 times per day.

Warnings & Precautions

Caution: Do not exceed recommended dose. Do not use if safety seal is damaged or missing.

Pregnant or nursing mothers, children under the age of 18, and individuals with known medical conditions should consult a physician before using this or any dietary supplement.

Pregnant or nursing mothers, children under the age of 18, and individuals with known medical conditions should consult a physician before using this or any dietary supplement.

Formulation Notes

Adrenal support

L-theanine + L-tyrosine + Ashwagandha + Desiccated adrenal

Additional Information

Store in a cool, dry place, with a lid.

To reorder: shop.drberg.com

Metadata

Product Details

DSLD Entry Date2025-07-24
Product TypeOther Combinations
FormCapsule
BrandDr. Berg
DSLD ID337162
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
View all evidence for L Theanine →
Compare

Similar Products

L-Theanine
XYMOGEN · Capsule
100
L-Theanine
XYMOGEN · Capsule
100
Thea-Zen
HBC Protocols · Capsule
100
L-Theanine 100 mg
Newflower Farmers Markets · Capsule
100
L-Theanine 200 mg
Vitamin World · Capsule
100
View all L Theanine products →
L Theanine research Best L Theanine All L Theanine products More from Dr. Berg View on NIH DSLD →

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