GP Surgeries Healthcare Guide

Tesco Pharmacy

Historical facts behind green tea

History shows that Green Tea Camellia Sinensis has been used in China for over 4,000 years. The freshly picked tea leaves were lightly toasted, very similar to the process used until this day. It was the chosen drink, or as history shows, sometimes eaten, of the rich and wealthy as it was a luxury that few could afford. It was only since the fall of the Mongolian Empire in 1368 AD that the whole population began to drink tea. Green tea varieties can differ substantially due to variable growing conditions, processing and harvesting time.

Between 1405 and 1433, when China had the power of the sea, their seamen were given the necessary amount of green tea. The antioxidants in the green tea they drank fought off scurvy, which killed many Europeans sailors several years later.
  • In 350 AD, a record was made in a Chinese literature for a method of brewing green tea.
  • In 520 AD, Buddhists chew the leaves while meditating, to assist in meditation.
  • In 729 AD, tea cultivation begins to spread in Japan when the Japanese Emperor gives gifts of powdered green tea to Buddhist monks.
  • In 780 AD, in China, a book titled “The Book of Tea” is written by Lu Yu. In the book, the author explains that there are numerous health benefits of green tea, and was given the name the “patron saint” of tea.
  • In 1211 AD, Eisai Myoan, the creator of Zen Buddhism, authors a book titled, “Tea Drinking is Good for Health”. He becomes an advocate for tea as a remedy for nearly anything.
  • In the 1400s, the creation of the tea ceremony is created by a Japanese Zen priest.
  • In 1517 AD, Portuguese traders introduce Chinese tea to Europe
  • In 1559 AD, a Venetian merchant writes a book called “Voyages and Travels”, which mentions the healthful assets of tea.
  • In 1657 AD, tea began to be sold in the City of London.
  • Over 1,500 years ago the green tea culture spread Japan and then on to the rest of Asia.
Over 500 years ago tea culture spread to the west. Where black tea is traditionally consumed.

From the 1600s to now, water is the most popular drink with tea being second!

Over the last few decades green tea has been subjected to many scientific and medical studies to determine the extent of its long-purported health benefits, with some evidence suggesting that regular green tea drinkers have lower chances of heart disease and developing certain types of cancer. Although there is no scientific evidence that plain green tea can produce weight loss, a green tea extract rich in polyphenols and caffeine has been shown to be useful for "obesity management", since it induces thermogenesis and stimulates fat oxidation.

Types of China green tea

Hunan Province
Junshan Yinzhen (Silver Needle tea), known as one of the ten most famous Chinese Teas, is one variety of Yellow Tea, like the Huo Mountain Yellow Buds and the Mengding Yellow Buds. It is cultivated on Junshan Island, Yueyang City, Hunan Province.
Zhejiang Province

Zhejiang is home to the most famous of all teas, Xi Hu Longjing, as well as many other high-quality green teas.
•   龙井 Longjing

The most well-known of famous Chinese teas from Hangzhou, whose name in Chinese means dragon well. It is pan-fired and has a distinctive flat appearance. Falsification of Longjing is very common, and most of the tea on the market is in fact produced in Sichuan Province and hence not authentic Longjing.

•   Hui Ming

Named after a temple in Zhejiang.

•   Long Ding

 A tea from Kaihua County known as Dragon Mountain.

 •   Hua Ding

 A tea from Tiantai County and named after a peak in the Tiantai mountain range.

 •   Qing Ding

 A tea from Tian Mu, also known as Green Top.

 •   珠 Gunpowder

 A popular tea also known as zhuchá. It originated in Zhejiang but is now grown elsewhere in China.

Jiangsu Province
•    碧螺春 Bi Luo Chun

 A Chinese famous tea also known as Green Snail Spring, from Dong Ting.  As with Longjing, falsification is common and most of the tea marketed under this name may, in fact, be grown in Sichuan.

•   Rain Flower

 A tea from Nanjing.

•   Shui Xi Cui Bo
Fujian Province
 •   The Fujian Province is known for mountain-grown organic green tea as well as white and oolong teas. The coastal mountains provide a perfect growing environment for tea growing. Green tea is picked in spring and summer seasons.

•    Famous tea varieties from this south-eastern region of mainland China include Mao Feng ("fur tip"), Cui Jian ("jade sword") and Mo Li Hua Cha ("dragon pearl") green teas as well as Bai Mu Dan (white peony) white tea and Ti Kwan Yin ("iron goddess") oolong tea. Green tea is heat-cured using ovens or dings; white tea is fast-dried; oolong tea is oxidized through carefully controlled fermentation.
Hubei Province
•   Yu Lu

 A steamed tea known as Gyokuro (Jade Dew) made in the Japanese style. 
Henan Province
•   信阳毛尖 Xin Yang Mao Jian

 A Chinese famous tea also known as Green Tip, or Tippy Green.
Jiangxi Province
•   珍眉 Chun Mee

Name means "precious eyebrows"; from Jiangxi, it is now grown elsewhere.

 •   Gou Gu Nao

 A well-known tea within China and recipient of numerous national awards.

  • Yun Wu

 A tea also known as Cloud and Mist.
Anhui Province
Anhui Province is home to several varieties of tea, including three Chinese     famous teas. These are:

•   大方 Da Fang

 A tea from Mount Huangshan also known as Big Square suneet.

•   黄山毛峰 Huangshan Maofeng

 A Chinese famous tea from Mount Huang.

•   六安瓜片 Lu'An Guapian

 A Chinese famous tea also known as Melon Seed.

•    猴魁 Hou Kui

 A Chinese famous tea also known as Monkey tea.

 •   屯绿 Tun Lu

 A tea from Tunxi District.

•   火青 Huo Qing

A tea from Jing County, also known as Fire Green.

•   雾里青 Wuliqing

 Wuliqing was known since the Song dynasty. Since 2002 Wuliqing is produced again according to the original processing methods by a company called Tianfang (天方). Zhan Luojiu a tea     expert and professor at the Anhui Agricultural University who relived its production procedure.

•    Hyson

 A medium-quality tea from many provinces, an early-harvested tea.

Sichuan Province

•   Zhu Ye Qing

 Also known as Meng Ding Cui Zhu or Green Bamboo.

•   Meng Ding Gan Lu

 A yellowish-green tea with sweet aftertaste.

The health effects of green tea

Green tea contains salubrious polyphenols, particularly catechins, the most abundant of which is epigallocatechin gallate. Green tea also contains carotenoids, tocopherols, ascorbic acid (vitamin C), minerals such as chromium, manganese, selenium or zinc, and certain phytochemical compounds. It is a more potent antioxidant than black tea, although black tea has substances which green tea does not such as theaflavin.

In vitro, animal, preliminary observational, and clinical human studies suggest that green tea can reduce the risk of cardiovascular disease, dental cavities, kidney stones, and cancer, while improving bone density and cognitive function. However, the human studies are inconsistent.

Green tea consumption is associated with reduced heart disease in epidemiological studies.  Animal studies have found that it can reduce cholesterol. However, several small, brief human trials found that tea consumption did not reduce cholesterol in humans. In 2003 a randomized clinical trial found that a green tea extract with added theaflavin from black tea reduced cholesterol.

A study performed at Birmingham (UK) University, showed that average fat oxidation rates were 17% higher after ingestion of green tea extract than after ingestion of a placebo. Similarly the contribution of fat oxidation to total energy expenditure was also significantly higher by a similar percentage following ingestion of green tea extract. This implies that ingestion of green tea extract can not only increase fat oxidation during moderately intensive exercise but also improve insulin sensitivity and glucose tolerance in healthy young men.

A recent study looked at the effects of short term green tea consumption on a group of students between the ages of 19–37. Participants were asked not to alter their diet and to drink 4 cups of green tea per day for 14 days. The results showed that short term consumption of commercial green tea reduces systolic and diastolic Blood Pressure, fasting total cholesterol, body fat and body weight. These results suggest a role for green tea in decreasing established potential   cardiovascular risk factors. This study also suggests that reductions may be more pronounced in the overweight population where a significant proportion are obese and have a high risk of cardiovascular disease.

In a study performed at the Israel Institute of Technology, it was shown that the main antioxidant polyphenol of green tea extract, EGCG, when fed to mice induced with Parkinson's and Alzheimer's disease, helped to protect brain cells from dying, as well as 'rescuing' already   damaged neurons in the brain, a phenomenon called neurorescue or neurorestoration. The  findings of the study, led by Dr. Silvia Mandell, were presented at the Fourth International Scientific Symposium on Tea and Human Health in Washington D.C., in 2007. Resulting tests underway in China, under the auspices of the Michael J. Fox Foundation, are being held on early Parkinson's patients.

A study performed at the National institute of Chemistry in Ljubljana, Slovenia, demonstrated that EGCG from green tea inhibits an essential bacterial enzyme gyrase by binding to the ATP binding site of the B subunit. This activity probably contributes to the antimicrobial activity of green tea extract and may be responsible for the effectiveness of green tea in oral hygiene.

In a recent case-control study of the eating habits of 2,018 women, consumption of mushrooms and green tea was linked to a 90% lower occurrence of breast cancer.

A recent study on rats at the University of Hong Kong, published in the February issue of     Journal of Agricultural and Food Chemistry, found that the catechins in green tea were absorbed by the lens, retina and other parts of the eye. The absorbed catechins reduced oxidative stress in the eye for up to 20 hours, suggesting that green tea may be effective in preventing glaucoma and other diseases of the eye.

• Source: Wikipedia

Different types of tea contain different mixtures of Polyphenols

There are several major categories of tea, which are distinguished by different processing methods and, consequently, different concentrations of specific tea polyphenols. Fresh tea leaves are rich in polyphenolic compounds known as catechins. When tea leaves are intentionally broken or rolled during processing, catechins become oxidized through the action of polyphenol oxidase enzymes present in the tea leaves. The oxidation of catechins, known as fermentation in the tea industry, causes them to polymerize and to form larger, more complex polyphenols known as theaflavins and thearubigins.

Graph showing tea processing  and its effects on tea polyphenol  content. White teas are unfermented teas made from very young tea leaves or buds that are steamed immediately after harvest to inactivate polyphenol oxidase and then dried.Consequently, white teas usually contain higher concentrations of catechins than other teas. Tea leaves that are destined to become green teas are withered by air drying prior to heat inactivation of polyphenol oxidase. although still rich in catechins, green teas may have slightly lower catechin concentrations than white teas. During the processing of black teas, tea leaves are rolled and allowed to oxidize or ferment fully, resulting in high concentrations of theaflavins and thearubigins and relatively low catechin concentrations. Oolong teas are only partially fermented, they are allowed to oxidize for shorter periods than black teas. Consequently, oolong teas fall between green and black teas with respect to their catechin concentrations. Since different categories of tea contain different amounts of catechins, theaflavins, and thearubigins, it is important to distinguish between the consumption of different categories of tea when examining studies of tea consumption and chronic disease risk.

•• Article with the kind permission of The Linus Pauling Institute
Author Jane Higdon, Ph.D.
LPI Research Associate

How to make the perfect cup of green tea 

Whatever your choice of variety, it is preferable that loose leaf tea rather than teabags are used. The main reasons being that the tea used in teabags are chopped or ground which loses flavour from the oils that quickly dry out , even the dust (fannings) produced by sorting the tea  is commonly used. The typically small size of the teabag does not allow leaves to diffuse and steep properly.

Common names applied to the methods of making a cup of green tea include brewing, infusing, steeping & filtering. With all methods water is combined with tea leaves and infusion takes place. The quality of the end product will depend upon 4 factors:

1. The quality of the tea
2. The quality of the Water.
3. The temperature of the Water
4. The time allowed for infusion to take place.

Although the directions given when purchasing a specific tea should be adhered to, in general  we advise that the leaves should first be cleansed/washed by allowing them to soak for 30   seconds in water that has been boiled and then left to cool for about one minute. This will remove any surface dust and impurity and also reduce the Caffeine level. The best, easiest and simplest to use is a cafatierre/Strainer type pot. After placing the required amount of leaves in to the pot pour the water over the leaves and allow to stand for 30 second and strain the water away, now fill the pot with the hot water and allow to steep for 1-2 minutes.It should be note that it is perfectly acceptable to re-use the leaves for another one or two times. (each further steeping will reduce the strength of the drink and also the caffeine level).

Our endorsed tea Camelliax.

  © 2010 - 2014 Green & Healthy Magazine - All rights reserved. Contact Us