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L-Theanine - Suntheanine®

Pure L-isomer Theanine
Suntheanine® 150 mg per capsule
Purest form of L-Theanine
Only one capsule per day
90 vegetarian capsules

Availability: In stock

EUR 24.95
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Doctors Best

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Product Description


The history of tea is long, complicated and spreads across multiple cultures and millennia. The origin of tea is most likely in the Chinese Yunnan during the Shang Dynasty (1500 BC-1046 BC). The medicinal drink "tea" was therefore the first to be described in a Chinese text.

In China, tea was first introduced to Portuguese priests
in the 16th century, who then took small amounts back to Portugal. Although the Portuguese were the first Europeans who came into contact with tea it were the Dutch who first imported tea on a wide scale. Tea quickly became a popular drink among the Dutch and from there it found its way to the rest of Europe where it was consumed mainly by the well-to-do.

Since its discovery, tea, has become the most consumed beverage in the world
after water and consumption is traditionally associated with vitality and relaxation. Unsweetened tea is composed of 99.5% water. Tea comes in many different configurations, types and flavors, but the traditional tea plant is Camellia sinensis. The leaves of this plant are used in black tea and green tea. The Camellia sinensis plant grows in tropical and subtropical countries and includes a range of phytochemicals such as flavonoids but also the special and natural amino acid L-Theanine.

In 1949, Japanese researchers discovered L-Theanine to be a component of tea, since this substance is widely studied. L-theanine is classified as a "non-protein" amino acid because it is not present in protein-rich food sources. One cup of tea contains about 20 mg of L-Theanine but the effective dose is about 200 mg.

After intake L-Theanine the molecule is taken up through the small intestine into the blood stream and then transported toward the brain. After passing through the blood-brain barrier, the effects of L-theanine take on. L-theanine is a glutamic acid analogue. Its properties are similar to those of GABA, an inhibitory neurotransmitter, as well as glutamate, a stimulating (excitatory) neurotransmitter.

The physiological effect of L-theanine is attained mainly through an increase of inhibitory neurotransmitters and a blocking of
excitatory neurotransmitters. Taking L-Theanine causes an increase of alpha-waves, and a decrease in beta-waves in the brain. Alpha waves are those between 8.0-13.0 Hz frequency, beta waves above 14.0 Hz frequency. These values correspond to specific states of mind.

This product only contains L-Theanine from the Suntheanine brand which provides the purest form. Note that L-Theanine products may also contain the inactive D-theanine form. The patented production process of Suntheanine ensures that of the Theanine they provide 100% consists of the L-shape.

Suntheanine has won an award for this product and in the United States has GRAS status meaning that it is deemed safe by the Food and Drug Administration (FDA).

Additional Information

Name L-Theanine - Suntheanine®
Brand Doctors Best
Content 90 capsules
User Instructions Take 1 capsule daily without food, or as recommended by a nutritionally-informed physician.
Serving Size 1 capsule
Ingredients per Serving 150 mg L-theanine (Suntheanine® pure L-isomer) †. † Recommended Daily Intake not established.
Other Ingredients Rice flour, modified cellulose (capsule).
Allergens Does not contain soy, wheat, gluten, lupine, peanuts, celery, mustard, nuts, sesame, milk, egg, fish, crustaceans or molluscs.
Suitable for vegans Yes
Suitable for vegetarians Yes
Gluten free Yes
Certified Organic N/A


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