ConsumerLab.com Answers  

Question:
Can L-theanine help as a sleep aid? Will ConsumerLab.com be testing these supplements?

Answer:
L-theanine is an amino acid found in green and black tea. When given as a supplement in amounts higher than in a cup of tea, preliminary studies suggest a number of effects, such as improving mental alertness, reducing stress, and enhancing the quality of sleep -- although it does not cause drowsiness.

ConsumerLab.com has tested the quality of popular brands of L-theanine. You can find out how these L-theanine supplements fared in the tests; how they compare on quality and ingredients; which offer the best value; and learn about proper dosage and potential side effects in ConsumerLab.com's Review of L-Theanine Supplements >>


See other recent and popular questions >>
COMMENTS

Anna16587   March 14, 2018
If one has sleep disorder known as alpha intrusion (alpha waves interrupt deep sleep delta waves), would taking L-theanine make that worse? are there any studies on this?

ConsumerLab.com   March 15, 2018
Hi Anna - As noted in the L-Theanine Supplements Review, there is some evidence that L-theanine may have an effect on alpha brain waves (https://www.consumerlab.com/reviews/L-Theanine-Supplements-Review/L-Theanine/#whatitdoes); however we are not aware of any research specifically on the effects of L-theanine supplementation in individuals with this sleep disorder.

ConsumerLab.com   January 13, 2015
Hi Don - Thank you for adding these studies! You can read more about these in the Encyclopedia article about L-theanine: http://www.consumerlab.com/tnp.asp?chunkiid=653856

Don384   January 12, 2015
Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. The effects of L-theanine, caffeine, and their combination on cognition and mood. Biol Psychol . 2008;77(2):113-122.

Don383   January 12, 2015
Kimura K, Ozeki M, Juneja LR, Ohira H. L-Theanine reduces psychological and physiological stress responses. Biol Psychol . 2007;74(1):39-45


Share your thoughts and comments about this topic in the space below. Please abide by the following rules:
  • If you make a statement of fact, such as whether a type of treatment does or does not work, state your basis -- such as personal experience or a published study.
  • If you make a positive or negative comment about a product, note whether or not you have a financial interest in the product or in a competing product.
  • Please be respectful in your tone.
  • Please do not submit any type of HTML markup or scripting as it will not be accepted, nor will comments that exceed 2,500 characters.
For your privacy, only your first name (from your account) followed by a random number will appear with your comment. Your last name and email address will not be displayed.
Comment:

Share your thoughts and comments about this topic in the space below. Please abide by the following rules:
  • If you make a statement of fact, such as whether a type of treatment does or does not work, state your basis -- such as personal experience or a published study.
  • If you make a positive or negative comment about a product, note whether or not you have a financial interest in the product or in a competing product.
  • Please be respectful in your tone.
  • Please do not submit any type of HTML markup or scripting as it will not be accepted, nor will comments that exceed 2,500 characters.
For your privacy, only your first name (from your account) followed by a random number will appear with your comment. Your last name and email address will not be displayed.
Comment:

You can modify your comment below. Please be aware the comment will have to approve the changes before they will be shown:
Comment:

Your edit has been submitted and is being reviewed by ConsumerLab.com prior to publication.
This CL Answer initially posted on 1/9/2015. Last updated 8/4/2017.
ConsumerLab.com members may submit questions to CLAnswers@ConsumerLab.com. We read all questions and try to answer those of popular interest.

 

   BECOME A MEMBER
JOIN NOW


Product Reviews

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

Herbs & Supplements

Conditions

Drug Interactions

Alternative Therapies

MEMBER TESTIMONIALS


Follow us on...
 
 
 
Join |  Sign In
   
Join Us on Facebook! Join Us on Instagram! Join Us on Twitter! Join Us on YouTube! Join Us on YouTube!
Product Tests
Brands Tested
Health Conditions
Encyclopedia
CL Answers
Clinical Updates
News
Recalls & Warnings
RDAs
Where to Buy Products
Raw Materials Tests
Testing Program
How Products Were Tested
Join CL Today
Testimonials
Join Free Newsletter
Group Subscriptions
Gift Membership
About Us
The CL Seal
CL Survey
Privacy Policy
Sitemap
Contact Us/Help

©2018 ConsumerLab.com, 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.
ConsumerLab.com name and flask logo are both registered trademarks of ConsumerLab.com, LLC. This site is intended for informational purposes only and not to provide medical advice.