This article is the final episode of the series. This time, I will introduce scientific topics about Zen and green tea.
Do you know the brain neurotransmitter called endorphin? Discovered in 1975, this substance acts similarly to morphine and is thought to be involved in the analgesic system and bring about euphoria. In addition, β-endorphin is said to activate NK cells and cure cancer spontaneously. It is said that zazen 座禅 produces β-endorphins, slows breathing, and enters a meditative state. In the electroencephalogram, the alpha wave, which is a characteristic of relaxation, appears.
Here, I introduce three of the seven brain substances that have a major effect on human brain activity. They are dopamine as a happiness substance, serotonin for peace of mind, and beta endorphins for sedative and pleasure chemical effects. The effect of β endorphins is famous as "Runners High", and the same effect can be obtained even for long walking, and it also stimulates dopamine secretion.
In the last episode, I told you that Japanese people in the Edo period were walking amazing distances. This may be because they were physically tired due to the effects of walking Zen, but they weren't so physically mentally exhausted.
Theanine contained in high-quality Japanese green tea has the same effect. Because black tea and Chinese tea are fermented teas, they don't include theanine. In addition, the amount of green tea, which is mass-produced in low-elevation areas of Japanese tea, is too high for catechins and the theanine is low. High-quality tea is produced with low solar radiation. Gyokuro of Kyoto Uji produced by artificial coating is famous. However, our green tea, which is produced in Japan's highest altitude and natural terroir, contains the highest amount of theanine. The altitude of the tea plantation is twice as high as that of Kyoto Uji. It doesn’t need artificial covering there.
Theanine is not only the Umami 旨味 ingredient in tea leaves, but a safe amino acid that was certified by the FDA in 2006 as a "food generally recognized as safe" (GRAS). Unlike GABA (γ-aminobutyric acid), theanine crosses the blood-brain barrier (BBB) and is a neurotransmitter that deeply affects important functions of the human body, such as human emotions and mental states, memory and motor functions, and sleep. It has been reported to affect the kinetics of noradrenaline, dopamine and serotonin. It is a relaxing ingredient and causes alpha waves to appear. It facilitates the production of beta endorphins by Zen. It would be rational for the samurai to had green tea called "Jindate 陣立て" before beginning of the war.
Not only that. Theanine has been reported to activate innate immunity. In the tragedy of the new coronavirus, scientists around the world are now looking for antibodies that are born from immune B cells and bind to the targeted new coronavirus. If we can do this, it will be a hope for humanity. Theanine activates the innate immune system itself. We are also studying a drinking style that maximizes theanine. At the same time, we also introduce a preventive method using EGCG, one of catechins, in my book.
“Japanese Tea Time: Why ZENJIRO Style is the Best Thing Since Sliced Bread (English Edition) “ Amazon Kindle and Apple Books
We all hope that the Zen and green tea style developed by the Japanese people will be accepted by many people around the world, leading to good health and well-being for all.