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Source Naturals

Serene Science L-Theanine

Serene Science L-Theanine

Item: SN387

  • L-Theanine from Source Naturals

  • Unique amino acid derived from the green tea plant

  • Supports natural relaxation

200 mg 60 Caps

Retail $33.98
Save 49%
In Stock
  • L-Theanine from Source Naturals

  • Unique amino acid derived from the green tea plant

  • Supports natural relaxation

L-Theanine from Source Naturals is a dietary supplement featuring this unique amino acid found almost exclusively in the tea plant (Camellia sinensis) and is the primary ingredient contributing to the unusual taste of green tea. Research has shown that L-theanine crosses the blood brain barrier, supports healthy neurotransmitter levels and inhibits the stimulatory properties of caffeine. Human studies have shown that taking L-theanine results in the emission of brain waves associated with a state of relaxation.

Terms and Ingredient Definitions

Product label for Source NaturalsSerene Science L-Theanine

Shipping Weight

.10 lbs

Source Naturals Serene Science L-Theanine Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

Serene Science L-Theanine is rated 4.5 out of 5 by 8.
Rated 4 out of 5 by from bmwtex My wife takes this product every evening to help her relax and sleep. it works very well for her and it was recommended to her by our family doctor. we have recommended it to several friends.
Date published: 2013-07-25
Rated 5 out of 5 by from great product I have tried many L-Theanine-and this is the best one I have found.
Date published: 2013-07-14
Rated 4 out of 5 by from Peaceful Sleep I heard this product can help you sleep better and fall asleep faster. Seems to be working for me!
Date published: 2013-04-22
Rated 4 out of 5 by from L-theanine my mom recommended that I take this product to help me sleep, and it really does work.
Date published: 2013-04-11
Rated 4 out of 5 by from L theanine IM seeing feeling results.
Date published: 2013-02-19
Rated 5 out of 5 by from Really helps I tr5ied these for about a week and I do see results that was not expected. There are so many products that makes claims that are never realized. With these I am more relaxed.
Date published: 2013-01-24
Rated 5 out of 5 by from As a women, with lots of things on my plate. It really helps me keep my self together, so I can be there for others.
Date published: 2012-11-06
Rated 5 out of 5 by from love it Dr Oz recommented this product it is great and the prices here are fantastic. Thanks for your great quality of product.
Date published: 2012-07-19
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Why Shop Swanson® Brands?

"With my personal 100% money-back satisfaction guarantee, you have nothing to lose and great savings to gain."

Lee Swanson, Founder of Swanson Health Products

Risk-Free Purchase Guarantee on Source Naturals Serene Science L-Theanine

If you are dissatisfied for any reason, we'll give you a full refund and pay return shipping.

Swanson's Standards

We are dedicated to offering the highest quality products at the best price. Find out more about how we ensure such a high standard in everything we do.

Learn More

200 mg 60 Caps

200 mg 30 Caps

200 mg 120 Caps

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© 2017 Ratings based on results of the 2017 Survey of Supllement Users. More information at
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