Theanine (L-Theanine) – Learn How It Can Help You


What Is It?

theanine green tea leavesL-Theanine  is one of many ingredients in the Tikva product. Theanine is an amino acid found in ordinary tea leaves from Camellia sinensis (also known as Thea sinensis, hence the name theanine, pronounced like tea-anene). It is also found in other species of Camellia and in the edible bay boletes mushroom Xerocomus badius, but is otherwise rare in nature. L-theanine has the reputation for promoting mental and physical relaxation-decreasing stress and anxiety-without inducing drowsiness. In the beverage tea, it has an influence on taste (reducing bitterness) and is said to counteract some of the nervous agitation that can come with caffeine. It has been indicated by laboratory studies that theanine increases the level of GABA (gamma-amino-butyric acid), an important inhibitory neurotransmitter in the brain. 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.

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Theanine Health Benefits

Relieve Stress and Anxiety

theanine relaxedThe calming effect of green tea may seem contradictory to the stimulatory property of tea’s caffeine content but it can be explained by the action of L-theanine. This amino acid actually acts antagonistically against the stimulatory effects of caffeine on the nervous system. Research on human volunteers has demonstrated that L-theanine creates a sense of relaxation in approximately 30-40 minutes after ingestion via at least two different mechanisms. First, this amino acid directly stimulates the production of alpha brain waves, creating a state of deep relaxation and mental alertness similar to what is achieved through meditation. Second, 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 the key relaxation effect.

Theanine readily crosses the blood-brain barrier of humans and exerts subtle changes in biochemistry. An increase in alpha waves has been documented, and the effect has been compared to getting a massage or taking a hot bath. Theanine is different than kava-kava in that it doesn’t cause drowsiness. And unlike tranquilizing drugs, it doesn’t interfere with the ability to think. Studies on rodents show just the opposite: theanine enhances the ability to learn and remember. By shutting down the “worry” mode, theanine increases concentration and focuses thought.

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Cardiovascular Support

Theanine has also been shown to prevent lipid peroxidation of LDL (low-density lipoprotein), a protective effect that also undoubtedly contributes to tea’s reputation for promoting cardiovascular health. Peroxidation of lipids is thought to play a role in the development of degenerative conditions such as atherosclerosis. Indeed, theanine appears to exert a variety of complementary, beneficial effects. Japanese researchers experimented on rats with elevated lipid and triglyceride levels caused by liver tumors. After adding powdered green tea and theanine to the rats’ diet, the scientists concluded that theanine was at least partially responsible for lowering cholesterol and triglyceride levels. While the blood lipid changes may have resulted solely from the decrease in tumor mass, the scientists speculated that both tea and theanine exert lipid-lowering effects. That explanation appears to be supported by the findings of another study, which determined that theanine plus green tea catechins, such as EGCG, reduced triglyceride levels in the serum and livers of laboratory mice. The mice also experienced a significant reduction in serum fatty acids while ingesting theanine and tea catechins, and lost significant body fat as well.

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theanine memoryL-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. The regulation of blood pressure is partly dependent upon catecholaminergic and serotonergic neurons in both the brain and the peripheral nervous system. Studies on spontaneously hypertensive rats (SHR) showed an impressive blood pressure lowering effect with L-theanine. The lowered blood pressure effect was dose-dependent with the highest test dose creating the most significant drop.

Neuroprotection and stroke

Theanine has been demonstrated to cross the blood-brain barrier. In an epidemiological study of nearly 6,000 women living in Japan, those who consumed five or more cups of green tea a day were significantly less likely than non-tea drinkers to suffer stroke. In a follow-up to the study, researchers determined that women who routinely drank little or no green tea were more than twice as likely as heavy tea drinkers to suffer stroke or cerebral hemorrhage.

Subsequent experiments have confirmed that theanine protects the brain from damage during ischemia, a condition in which the brain temporarily receives too little oxygen due to reduced blood flow, which may result from stroke. A recent Japanese study showed that theanine significantly protects the brain after an ischemic incident occurs.

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Priming Immunity

theanine immune systemIn human experiments, subjects consumed either tea (containing caffeine and a known amount of theanine ) or coffee, which also contains caffeine but not theanine. Blood tests showed that tea drinkers, but not coffee drinkers, saw increased production of an important disease-fighting cytokine by their T cells. When pathogens invade, their surfaces often bristle with alkylamines similar to those found in tea. T cells that have been primed by prior exposure to theanine are better equipped to promptly recognize and neutralize the microbial threat. The Harvard researchers concluded, “These data provide evidence that dietary intake of tea . . . containing alkylamine antigens or their precursors [for example, theanine ] may prime human [gamma] [delta] T cells that then can provide natural resistance to microbial infections

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Japanese researchers have discovered that theanine works for PMS. Using a distress questionnaire, they tracked the reactions of 20 women taking the new supplement for two months. Theanine caused documented reductions in mental, social and physical symptoms. Women who benefited took 100 mg of theanine twice a day during the questionable days.

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