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100 mg, 60 vegetarian capsules
Item# 01683



Promotes a calming and mood-enhancing effect

100 mg, 60 vegetarian capsules
Item# 01683


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  • L-Theanine
  • 100 mg, 60 vegetarian capsules
  • Item Catalog Number: 01683

Theanine is the predominant amino acid of tea that produces calming effects in the brain by increasing levels of serotonin and dopamine, and blocking the binding of L-glutamic acid to glutamate receptors.1-18 Life Extension customers can enjoy the benefits of this unique ingredient in a 100 mg supplement. This "feel good" supplement causes no adverse reactions. In fact, in Japan, theanine is added to soft drinks and chewing gum for the purpose of inducing relaxation.

The calming, mood-enhancing effect is achieved by helping to increase alpha-brain waves, electrical brain activity commonly present when you are very relaxed, literally putting you in a better mood.7

Just as meditation, massage or aromatherapy quiets the mind and body, theanine plays a role in inducing the same calm and feeling of well-being. It is a non-toxic, highly desirable mood modulator.

Beware of Imitations: The L-theanine used in this product is Suntheanine®, the only pure form of L-theanine protected by 40 U.S. and international patents and scientifically proven in clinical studies to be safe and efficacious. Independent laboratory analysis has verified that certain other products on the market claiming to contain "L-theanine" are only half L-theanine, the other half being a different form of theanine known as "D-theanine" which has not been scientifically evaluated in published studies.

These statements have not been evaluated by the Food and Drug Administration.
These products are not intended to diagnose, treat, cure, or prevent any disease.

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  2. Journal of Functional Foods, Volume 3, Issue 3, July 2011, Pages 171-178
  3. Phytother Res. 2011 Nov;25(11):1636-9.
  4. Trends Food Sci Technol 10 (1999), 199–204.
  5. J Physiol Anthropol. 2012 Oct 29;31(1):28. 
  6. Biol Pharm Bull. 2002 Dec;25(12):1513-8.
  7. J Herb Pharmacother. 2006;6(2):21-30.
  8. Biol Psychol. 2008 Feb;77(2):113-22. 
  9. Free Radic Biol Med. 2009 Dec 1;47(11):1601-10.
  10. Biochem Biophys Res Commun. 2004 Jul 16;320(1):116-22.
  11. Neurotoxicology. 2008 Jul;29(4):656-62. 
  12. J Med Food. 2011 Apr;14(4):334-43.
  13. Pharmacol Res. 2011 Aug;64(2):162-8.
  14. Biological & Pharmaceutical Bulletin, 25, 1513e1518.
  15. LWT - Food Science and Technology 46 (2012) 64e70
  16. J Sci Food Agric. 2011 Aug 30;91(11):1931-9.
  17. Neurochem Res. 1998 May;23(5):667-73.
  18. Brain Topogr. 2009 Jun;22(1):44-51.


Supplement Facts

Serving Size 1 vegetarian capsule

Amount Per Serving

Vitamin C (as ascorbyl palmitate)

2 mg

Suntheanine® (L-Theanine)

100 mg

Other ingredients: microcrystalline cellulose, vegetable cellulose (capsule).


Suntheanine® is a registered trademark of Taiyo International, Inc. Use of Suntheanine® is protected by U.S. Trademark Reg. No. 2548957.

Dosage and Use
  • Take one (1) capsule one to four times daily with or without food, or as recommended by a healthcare practitioner.


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