Vitamin supplements guide   Vitamins & health supplements guide

Theanine quick review
Description: a naturally occurring non-protein amino acid, mainly found naturally in tea leaves (Camellia sinesis) and other species of Camellia.
Health benefits: promotes mental and physical relaxation, controls anxiety, increases mental focus, improves concentration, and promotes creativity.

Sources & dosage: tea leaves (Camellia sinesis), edible bay boletes mushrooms (Xerocomus badius). Dosage ranges between 50 and 200 mg daily.
L-Theanine by Enzymatic Therapy
L-Theanine is a special amino acid-the same found in green tea-that helps promote a restful, relaxed state while maintaining daytime alertness. L-Theanine is also scientifically shown to support healthy blood pressure levels that are already within normal range. L-Theanine by Enzymatic Therapy is manuafactured according to the highest pharmaceutical standards and uses only the best quality raw ingredients. Click here for more information.


Theanine (5-N-ethyl glutamine) is a naturally occurring non-protein amino acid. It is mainly found naturally in tea leaves (Camellia sinesis) and other species of Camellia, as well as edible bay boletes mushrooms (Xerocomus badius). L-theanine is the predominant amino acid in green tea and makes up 50% of the total free amino acids in the plant. Theanine is considered to be the main component responsible for the taste of green tea. The amino acid constitutes between 1% and 2% of the dry weight of green tea leaves. In tea extracts, it is usually found closely associated with the phenolic fraction, and is generally believed to modify the astringency of tea polyphenols.


Theanine functions, uses, and health benefits

L-theanine is involved in the formation of the inhibitory neurotransmitter, gamma amino butyric acid (GABA). GABA influences the levels of two other neurotransmitters, dopamine and serotonin, producing a relaxation effect. GABA serves a sedative function that
brings balance to excitability that can lead to restlessness, insomnia, and other disruptive conditions. Theanine also appears to increase levels of dopamine, another brain chemical with mood-enhancing effects, which can reduce blood pressure.

L-theanine is an amino acid that helps promote a mild, restful, relaxed state without diminishing daytime alertness. Stress impairs the immune system, leaving us vulnerable to opportunistic infections, and can cause depression. People under stress can mitigate many of the harmful effects of stress with l-theanine. L-theanine reduces stress and anxiety without the tranquilizing effects found in many other calming supplements.

Theanine has a reputation for promoting mental and physical relaxation, and decreasing stress and anxiety without inducing drowsiness, as measured by increased generation of alpha-waves. L-theanine directly stimulates the production of alpha brain waves. By increasing the brain's output of alpha waves, theanine may control anxiety, increase mental focus, improve concentration, and promote creativity.

Theanine may improve learning ability and sensations of pleasure by affecting dopamine and serotonin neurotransmitters in the brain. L-theanine has a significant effect on the release or reduction of neurotransmitters like dopamine and serotonin, resulting in improved memory and learning ability. L-theanine may also influence emotions due to its effects on the increased release of dopamine. L-theanine reduces brain serotonin concentration by either curtailing serotonin synthesis or increasing degradation in the brain. Theanine exerts protective effects on the brain by antagonizing glutamate toxicity.

Theanine has been found to be increasingly associated with therapeutic benefits in the areas of cardiovascular health and cancer treatment. Theanine helps to reduce the side effects and enhance the antitumour efficacy of chemotherapy. L-theanine has exhibited anticancer effects and an ability to favorably modulate the activity of some anticancer drugs.


Theanine dosage, intake

An effective dosage of l-theanine is between 50 and 200 mg daily, as required. Individuals with high stress levels may increase their dosage of L-theanine to at least 100 mg, with no more than 600 mg being taken in a six hour period. FDA recommends a maximum dose of 1200 mg daily.