All-natural L-theanine from green tea extract

L-theanine is an amino acid that is not widely found in our diet and does not belong to the essential and even the non-essential amino acids. It is mainly found in substantial amounts in the leaves of Camellia sinensis, the plant used to produce green, black and white tea.

But for a therapeutic dose, a supplement is necessary!


In terms of structure, L-theanine is similar to glutamine and two neurotransmitters produced from it, namely GABA and glutamate. L-theanine is also called
r-glutamylethylamide and is commonly known as a calming amino acid.

Kinetics and mechanisms

L-theanine has been shown to cross the blood-brain barrier. After oral ingestion, L-theanine reaches the brain within an hour and is elevated for 5 hrs. Thereafter, it is gradually eliminated and has completely disappeared from the body after 24 hours. It has been shown that the L-theanine concentration increases i.a. in the hippocampus when taken orally.

L-Theanine supplements cause an increase in the production of alpha-1 waves within 30-45 minutes after oral intake of about 100 mg. This provides the most common benefits such as relaxation and attention.

Contact us


Animal studies show that L-theanine is remarkably safe, as very high doses have not caused any toxicity.

Why choose Thearelax™?

  1. 1.
    Sourced from a world-renowned supplier of green tea extract,
    rich in L-Theanine
  2. 2.
    Contains all-natural L-theanine and not via chemical synthesis
  3. 3.
    Standardized on 40 % L-Theanine
  4. 4.
    Water extraction and therefore no use of synthetic solvents
  5. 5.
    A proprietary extraction process
  6. 6.
    Excellent water solubility and stability -> ideal for functional food applications
  7. 7.
    cGMP, FSSC 22000 and HACCP certified
  8. 8.
    SGS tested for Pesticide Residuals, PAH (4) and Pyrrolizidine Alcaloids
  9. 9.
Contact us

Health benefits

  1. Reduces anxiety and stress
  2. Induces a good feeling of relaxation without causing sedation or drowsiness
  3. Has attention-promoting properties
  4. Improvement of the sleep quality (deeper sleep)
  5. Beneficial effect on blood pressure

Technical data

Common Name
Thearelax™ – green tea extract
Botanical Origin
Camellia sinensis
Standardized on 40 % L-Theanine
Nutritional supplements and functional food
Recommended dose
100 – 400 mg per day
Thearelax™ is a trademark of Fermedics BV.