In the News - Press Coverage     Testimonials     Press Releases

Feeling Stressed? Reviews the Evidence for L-Theanine and Test Popular Products

White Plains, New York, August 21, 2015 — L-theanine is often promoted to reduce stress, and for conditions such as ADHD — but does it really work? recently reviewed the evidence and purchased popular brands of L-theanine to test their quality. While products selected for testing contained their claimed amounts of L-theanine and met other quality criteria, they differed significantly in dose and price, with some high quality supplements costing nearly one-third less than other brands.

The test results and quality ratings appear online in's new L-Theanine Supplements Review. The report covers 8 products selected by, and three others which passed the same tests in's voluntary Quality Certification Program. Also included is one product similar to one which passed testing but which is sold under a different brand name. The report discusses the evidence for L-theanine and doses have been found to be effective in clinical studies. Information about safety, side-effects and potential drug-interactions is also presented.

The following products are included in the report: Bluebonnet L-Theanine, Country Life 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 and Vitamin World L-Theanine.

Founded in 1999, is a leading provider of consumer information and independent evaluations of products that affect health and nutrition. Membership to is available online and provides immediate access to reviews of more than 1,000 products from over 400 brands. The company is privately held and based in Westchester, New York. It has no ownership from, or interest in, companies that manufacture, distribute, or sell consumer products.

— END —

back to top



Coronavirus Information Center
Coronavirus Information Center
Answers to Critical Questions About COVID-19.

Product Reviews

In addition to our product reviews our encyclopedia covers the following:

Herbs & Supplements


Drug Interactions

Alternative Therapies



Follow us on...
facebook twitter
Join |  Sign In
Join Us on Facebook! Join Us on Instagram! Join Us on Twitter! Join Us on YouTube! Join Us on YouTube!
Product Reviews
Brands Tested
Health Conditions
CL Answers
Clinical Updates
Recalls & Warnings
Recommended Intakes
Where to Buy Products
Testing Program
How Products Were Tested
Quality Certification Program
Join CL Today
Join Free Newsletter
Group Subscriptions
Gift Membership
About Us
The CL Seal
CL Survey
Privacy Policy
Contact Us/Help

©2020, LLC. All rights reserved. A single copy of a report may be printed for personal use by the subscriber. It is otherwise unlawful to print, download, store or distribute content from this site without permission. name and flask logo are both registered trademarks of, LLC. This site is intended for informational purposes only and not to provide medical advice.