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L-theanine Green Tea Nutritional Supplement for Relaxation and Concentration

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  • L-theanine is studied as the substance potentially responsible for all the relaxing and psychoactive benefits of tea.
  • Green tea helps feel calmer and relaxed without inducing drowsiness.
  • Helps clear the mind and improve memory and concentration.
  • 100% natural extract of green tea (Camellia sinensis) with a high dose of L-theanine.
Please note: this label has recently changed its graphic design, but rest assured: the composition of the product has remained strictly the same.

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60 Veg. Caps



60 Veg. Caps



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No controversial excipients
No sweeteners

L-theanine is one of the best-known and most extraordinary active ingredients in tea. It is studied extensively for its potential role in several of tea’s key effects (green tea in particular): restoring calm and relaxation, mental clarity, memory, concentration, etc.

Natural, high-strength, and particularly effective, our L-Theanine supplement is part of our Stress & Mood category.

L-Theanine: Definition and Benefits

What is theanine ?

L-theanine, or simply theanine, is a non-proteinogenic amino acid found mainly in green tea.

It is not to be confused with theine, which refers to the caffeine found in tea.

The benefits of L-theanine from green tea

Green tea has a number of recognized health benefits, some of which scientists attribute to its L-theanine content. These include, in particular:

  • Its relaxing effect: green tea helps relax, especially during periods of stress. The L-theanine it contains easily crosses the blood-brain barrier and is thus thought to exert calming benefits directly in the brain, benefits which have been compared to those produced by massage, meditation, and aromatherapy. Specifically, theanine may act by stimulating the production of soothing neurotransmitters. In addition, green tea promotes relaxation without causing drowsiness, an effect measurable by the increase in generation of alpha waves in the brain (1).
  • Its psychoactive properties: green tea's action on alpha waves helps feel calmer but at the same time, more attentive. It improves ability to concentrate, learn, and memorize. In Japan, chewing-gum, ice creams, and 'soft drinks' fortified with L-theanine are popular with students during exam periods (2-3).
  • Its ability to improve sleep: by aiding relaxation and reducing anxiety, green tea facilitates natural nighttime sleep and helps reestablish restful, restorative sleep.

Two Key Strengths of our L-Theanine Supplement

SuperSmart’s L-Theanine supplement is notable in 2 important respects:

  • Its 100% natural composition: L-Theanine is an all-natural extract of green tea (Camellia sinensis) standardized in L-theanine, not a synthetic L-theanine supplement.
  • Its powerful, safe, and effective dose: our supplement provides 1,000 mg of green tea extract a day, based on a daily dose of 4 capsules. As it is standardized to 40% L-theanine, these 4 capsules provide an excellent 400 mg of L-theanine a day, a dose considered safe and particularly effective (4).


Do not exceed the recommended daily dose. This product is a nutritional supplement and should not be used as a substitute for a varied and balanced diet or a healthy lifestyle.


Store in a cool, dry place away from direct sunlight, heat, and humidity. Keep out of reach of children.


If you are pregnant, breastfeeding, or have any medical conditions, consult your healthcare provider before using this product.


Consult your healthcare provider before use, especially if you are taking any medications or other supplements as there may be potential interactions.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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