- What is L-theanine? Often just called theanine, L-theanine, is a water-soluble amino acid found in black and green tea (See What It Is).
- What are the health benefits of L-theanine? Some small clinical studies (funded by manufacturers of L-theanine) have found L-theanine may reduce stress, anxiety and blood pressure in stressful situations, but not all studies have found a benefit (See What It Does).
- How much L-theanine should I take? L-theanine is typically taken at a dose of 200 mg to 400 mg per day (See Dosage).
- L-theanine safety and side effects: At these doses, it appears to be generally safe, but there are possible interactions with blood pressure medications and benzodiazepines (See Concerns and Cautions).
- Best value for L-theanine: ConsumerLab.com did not find problems with the quality of selected L-theanine products sold in the U.S., but did find large differences in the cost to obtain L-theanine. The least expensive, Approved product cost 22 cents to obtain 200 mg of L-theanine while the cost was often 60 cents for other products (See What CL Found).
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L-Theanine Supplements Review
Find the Best L-Theanine Supplement. Find Out If L-Theanine Helps for Stress and Which Products Are Best.
Medically reviewed and edited by Tod Cooperman, M.D.
Alphabetical list of L-theanine supplement brands compared in this review
Bluebonnet L-Theanine
Country Life L-Theanine
GNC L-Theanine
Jarrow Formulas L-Theanine 200
Life Extension L-Theanine
NOW L-Theanine Double Strength
Puritan's Pride L-Theanine
Solgar L-Theanine
Source Naturals L-Theanine
Swanson Ultra Suntheanine
Thorne Research Theanine
TwinLab L-Theanine Dots
Vitamin World L-Theanine
Make sure the L-theanine supplement you take passed our test and is right for you!
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Summary
You must join to see the full review and test results for L-theanine supplements along with ConsumerLab.com recommendations and quality ratings. You'll get test results and quality ratings for 8 supplements selected for review by ConsumerLab.com, plus 4 others which passed the same tests through ConsumerLab.com's voluntary, Quality Certification Program. Plus, you'll learn:
- Which L-theanine supplements failed testing and which passed
- Differences in the marketed forms of L-theanine
- The best L-theanine supplements at the lowest cost
- The dosage of L-theanine taken for different applications and the related clinical evidence
- Potential side effects and drug interactions of L-theanine supplements
- Tips for buying and using L-theanine, and more!
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Related CL Answers (7)
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