Tea and Health 茶と健康

ーTea began as a medicine and grew into a beverage. 『The Book of Tea』

Tea was brought to Japan by a monk, who practiced Zen in China (Song dynasty), because of its medical efficacy. And so tea was spread among monks, generals or aristocracy people, then gradually to samurai and ordinary people. The culture of tea drinking had become the Japanese tea ceremony : Sado (Chado) and Senchado and they have been passed down for generations until now.

Japanese green tea, which has the original flavor incuding Shibumi (astringenc), Nigami (bitterness), Amami (sweetness) and Umami contains many healthy components. And nowadays, its various effects are known world widely.

〔Main Components of Green Tea〕

・CATECHIN (component of Shibumi) :  blood cholesterol-reduction, body fat-reduction, prevention of cancer, anti-oxidant, prevention of tooth decay, anti-microbial action, anti-influenza virus action, inhibition of blood pressure increase, inhibition of blood sugar increase, prevention of mouth odor (bad breath)

・CAFFEINE (component of Nigami) : waking effect, enhancing exercise stamina, preventing hangovers, diuretic effect, stimulates digestive system

・THEANINE (component of Umami) : neuroprotective activity, relaxation effect (α wave)

・VITAMIN C/B2 : health maintenance of the skin and mucous membranes

・FOLIC ACID : prevention of arteriosclerosis

・BETA CAROTENE : maintaining night vision

・MINERAL : organism adjusting function, essential nutrients

Ever since I started to share about Japanese tea culture here, on YouTube (Tea Video Letter) and on Instagram, I received questions about tea and tea culture. 

Recently I was informed there are a few people who feel nauseous or dry-throat/dry-mouth after drinking green tea. After researching some of the reasons, I reached some possibilities. I want to share them in this article.

1. ー Because of Caffeine? 

I assume many people are familiar with the effects of caffeine. It is contained in coffee, a variety of teas (Sencha, Matcha, Gyokuro, Oolong, Black tea ... ) or coke. Even though you can gain good effects by taking caffeine, having too much causes side effects such as headaches, sleep deprivation or frequent urination. Caffeine has a strong stimulating effect on the human body so you should be careful of how much or when to take it. It's said that the body absorbs approximately 100% of the caffeine you take within 45 min. and the effect would be reduced after 4 ~ 6 hours.

But how much each component affects on you depends on each person's physical constitution or condition. So I can't mention the detail clearly. For example, some people have no sleep disorder problems even they drink coffee or tea before sleeping.

〔 Some information I found on internet 〕☆ People who don't often take caffeine would be affected by caffeine more easily and sensitively. ☆ Women metabolize caffeine faster than men. ☆Smokers metabolize caffeine twice as fast as non-smokers. ☆Asian people have a lower speed of metabolism.    

2. ー Why nauseous?

This is my experience when I was taking the Sado lessons in Kyoto. Whenever there was a class, students could attend and leave anytime during the afternoon session (1 p.m. ~ 5 p.m.) to the night session (6 p.m. ~ 10 p.m.) by each schedule (if it's told). So I often attended the class for about 4 ~ 8 hours. During the day, I sit in "seiza" position for many hours (but of course, it's allowed to sit in relaxing style or stand up, depending on the situation). One day, I attended the class from 2 p.m to 10 p.m. ( ... lol ) I was going to leave the class around 9 actually, but the teacher offered a cup of Koicha which is two or three-times thicker compared to the usual matcha / Usucha, because the Koicha practice was about to begin. And soon after I sip of the Koicha, I fainted and fell on the Tatami mat. I figured out my blood circulation was bad because of having to keep sitting in the same position for many hours while being hungry and having to keep focus or being nervous. And in the formal tea ceremony of Sado, Koicha should be drunk after a meal. The formal order is 1. eat a Kaiseki meal (and drink Sake) → 2. eat a moisture sweets (main sweets) as a desert for the meal → 3. share a cup of Koicha (think matcha) with other guests → 4. eat a dried sweets (sub-sweets) → 5. drink a cup of Usucha (thin matcha) . But in the most of tea gatherings (or during practice), the ceremony is simplified to  < 2. &  5. part >.

Especially taking caffeine when you are hungry is not good for your stomach.  Caffeine stimulates the secretion of stomach acid, and an empty stomach absorbs food more easily. So it could be the reason you feel nauseous. Taking caffeine after eating could be better. 

3. ー The relationship between Caffeine and Dry throat/mouth

Caffeine has a diuretic effect. So it could be the cause for a dry throat and mouth. As water is discharged by caffeine, you would feel your throat or mouth dry out. For the purpose of hydration, drinking water is the best choice. 

4. ー Recommendation of "水出し緑茶/煎茶 Mizudashi Ryokucha/Sencha (extracting tea by cold water)"

Recently, I saw on TV program that Mizudashi Ryokucha could make you feel relaxed before sleeping. By serving tea in cold water (or with ice cubes), the extracted components would be different from ones by hot water. Caffeine and catechin would be extracted less and theanine would be more.　As theanine has the relaxing effect, it is good to drink when you want to sleep. Caffeine is extracted by hot water over 80℃ (according to the article I read ...!). 

 It's said that there is also a component you can get by Mizudashi Ryokucha. It's called epigallocatechin. Epigallocatechin improves one's immune system. 

But in that case, you can't get the good effects of catechin. So please choose and enjoy what kind of tea and how to make it by the occasion, your mood or condition.

And if you make Mizudashi Ryokucha, it means you won't eliminate chlorine in water because you won't boil water, so please be careful for the water you use.

Please refer them as one opinion/information. 

I love drinking Japanese teas. But for me, tea isn't just a drink to be healthy or something to pursue or compete for the best color, odor or taste. Like there is a quote "Tea is a liquid wisdom.", drinking tea and enjoying the moment of having tea in your life is to maintain your spirit good and pure and to have a life filled with grace and richness in mind.