GREEN TEA

Chinese Green Tea: We have discussed for weeks the many points of Chinese history as a result of Tea being discovered by Shen Nung in 2373 A.D. Here is a small history of China to match the Tea events.

History of China & Man
As tea has such a long history I felt it important to discuss the timeline of Chinese History as well as the history of man as we know it today.

Chinese Pre-history
Archeological evidence suggests that the earliest occupants in China date back as far as 2.24 million to 250,000 years ago by an ancient human relative (hominin) known as Homo Erectus. One particular cave in Zhoukoudian (near current-day Beijing) has fossilized evidence, that current dating techniques put somewhere between 300,000 and 550,000 years old.

Evidence of primitive stone tool technology and animal bones in association to Homo Erectus have been studied since the late 18th and 19th centuries in various areas of Eastern Asia including Indonesia (in particular the Island of Java) and Malyasia. Originally it is thought that these early hominids first evolved in Africa during the Pleistocene and that human first took place in Africa expanding over 7 million years. 2 million years ago the first wave of migration from the species in association with Homo Erectus settled into various areas in the Old World.

Fully modern humans (Homo sapiens) are believed to originally have evolved roughly 200,000 and 168,000 years ago in Ethiopia or Southern Africa (i.e. Homo Sapiens idaltu). 100,000 to 50,000 years ago the modern human beings settled in all parts of the Old world (including the New World, Americas 25,000 to 11,000 BC).

By less than 100,000 years ago all proto-human populations disappeared as modern humans took over or drove other human species into extinction. It remains a controversial subject as to whether fully modern humans evolved from separate Homo Erectus populations (known as "multiregional"). Some evidence in ancient skeletal bones shows a transitional change from Homo Erectus to Homo Sapiens having archaic features. However it is now more widely accepted that all modern humans genetically share a direct ancestor, a female nicknamed “Mitochondriallll Eve" from Eastern Africa 150,000 years B.C. This model is known as Mitochondrial Eve Hypothesis.

The earliest evidence examples of fully modern humans in China come from Liujiang, China where a cranium dates 67,000 years B.C. Another is a partial skeleton from Minatogawa believed to be only 18,000 years old.

History
China was one of the earliest centers of human civilization. Chinese civilization was also one of the few to invent writing independently, the others being ancient Mesopotamia (Sumerians), India (Indus Valley Civilization), the Mayan Civilization, and Ancient Egypt. The Chinese script is still used today by the Chinese and Japanese, and to a lesser extent by Koreans and Vietnamese. This script is the only logographic script still used in the world.

The first dynasty according to Chinese sources was the Xia Dynasty, but its references have traditionally been believed to be legendary. Until scientific excavations were made at early bronze-age sites at Erlitou in Henan Province, it was difficult to separate myth from reality in regard to the existence of the Xia Dynasty. However since then, archaeologists have uncovered urban sites, bronze implements, and tombs that point to the possible existence of the Xia Dynasty at the same locations cited in ancient Chinese historical texts.

The first reliable historical dynasty is the Shang, who settled along the Huang He River from eastern China, dating from the 18th to the 12th centuries B.C. The Shang were in turn invaded from the west by the Zhou (12th to 5th centuries B.C.), whose centralized authority was slowly eroded by the ceding of state-like authority to warlords ruling small states; eventually, in the Spring and Autumn period, many strong independent states, in continuous war, paid but nominal deference to the Zhou state as the Imperial centre. They were all unified under one emperor in 221 BC by Qin Shi Huang, ushering in the Qin Dynasty, the first unified, centralized Chinese state.

This state, however, did not last for long, as its legalist approach to control soon led to widespread rebellion. After the fall of the authoritarian Qin Dynasty in 206 B.C. came the Han Dynasty which lasted until 220 A.D. A period of disunion followed again.

In 580, China was reunited under the Sui. Under the succeeding Tang and Song Dynasties, China reached its golden age. For a long period of time, especially between the 7th and 14th centuries, China was one of the most advanced civilizations in the world in technology, literature, and art, although change was very gradual and mitigated by Imperial powers. The Song Dynasty fell to the invading Mongols in 1279. The Mongols, under Kublai Khan, established the Yuan Dynasty.

A peasant named Zhu Yuanzhang overthrew the Mongols in 1368 and founded the Ming Dynasty, which lasted until 1644. After the Ming dynasty, came the Qing (Manchu) Dynasty, which lasted until the overthrow of Puyi in 1911.

Oftentimes regime change was violent and strongly opposed and the ruler class needed to take special measures to ensure their rule and the loyalty of the overthrown dynasty. For example, after the foreign Qing (Manchus) conquered China, because they were ever suspicious of the Han Chinese, the Qing rulers put into effect measures aimed at preventing the absorption of the Manchus into the dominant Han Chinese population. However, these restrictions proved ineffective against the assimilation of Manchus into the Chinese identity and culture.

In the 18th century, China achieved a decisive technological advantage over the peoples of Central Asia, with which it had been at war for several centuries, while simultaneously falling behind Europe in that respect. This set the stage for the 19th century, in which China adopted a defensive posture against European imperialism, while itself engaging in imperialistic expansion into Central Asia.

However the primary cause of the decline of the Chinese Empire was not European and American interference, but rather the consequence of a series of internal upheavals. Most prominent of these was the Taiping Civil War which lasted from 1851 to 1862, similar in nature to our own Civil War.

The civil war was started by an extremist believer, in a school of thought partly influenced by Christianity, who believed himself to be the son of God and the younger brother of Jesus. Although the imperial forces were eventually victorious, the civil war was one of the bloodiest in human history - costing at least twenty million lives (more than the total number of fatalities in the First World War), with some estimates upward of 30 million.

Prior to this conflict, a number of Islamic Rebellions, especially in Central Asia, had occurred. Later, a second major rebellion took place, although this latter uprising was considerably smaller than the cataclysmic Taiping Civil War.

This second conflict was the Boxer Rebellion which aimed to repel Westerners. Although secretly supporting the rebels, the Empress, Ci Xi, made public efforts to aid foreign forces in suppressing the uprising. In the end the Boxers were defeated by the Eight-Nation Alliance.

At the 1924 inauguration of the Whampoa Military Academy, Sun Yat-sen delivered a speech that would later become the lyrics of the ROC's national Anthem.

I n 1912, after a prolonged period of decline, the institution of the Emperor of China disappeared and the Republic of China was established. The following three decades were a period of disunion — the Warlord Era, the Sino-Japanese War, and the Chinese Civil War.

The latter ended in 1949 with the Communist Party of China in control of mainland China. The CPC established a communist state—the People's Republic of China—that laid claim to be the successor state of the Republic of China.

Today, China's pre-CPC ruling government has become a fully governing body in Taiwan, which has official diplomatic relations with less than 30 countries. The majority of the international community recognizes the "One China policy" which considers the PRC as the only legitimate government in China. In addition, the PRC disputes Taiwan's status as an independent country from the Mainland. However, in recent years, some of the people of Taiwan, led by Chen Shuibian have pushed for, but failed to recieve a separate political indentity from the Mainland.

The United Kingdom and Portugal transferred their colonies of Hong Kong and Macau on the southern Chinese coast to the PRC in 1997 and 1999, respectively.

The PRC does not recognize the ROC, as it claims to have succeeded the ROC as the legitimate governing authority of all of China including Taiwan. On the other hand, the ROC—while never formally renouncing its earlier claims or changing official maps that show its territory as including both the modern-day PRC and Tibet—has moved away from this former identity representing its rule over all of China, and increasingly identifies itself as Taiwan. The PRC has historically resisted the ROC's identification of itself as Taiwan, especially in light of the movement supported by residents of Taiwan and others who advocate Taiwan's identity as an independent political entity. Significant disputes persist as to the nature and extent of China, possible Chinese reunification and the political status of Taiwan.

Chinese Green Tea

History of Green Tea
1. As we already know, Green Tea is an unfermented tea which derives its distinct flavor from the area in which it is grown and the techniques used to produce the tea like the picture below.

2. The Principle Chinese provinces producing green tea are Anhwei, Chekiang and Kiangsi and to a smaller extent, Fukien, Kwangtung and Hunan.

3. China greens grow from June to December - the early teas are generally the best BUT many very expensive greens are plucked in November and December.

4. There are over 12,500 green teas produced in China and they are named many times for no apparent reason or purpose and then, for no apparent reason or purpose, they are re-named and re-named When I referred to 12,500 China green teas, that is merely an educated guess. No one knows for sure, absolutely no one.

5. Not many visitors have ever set foot in the very best China tea gardens. These remain shrouded in mystery and are quite secret. Few Chinese even know that these gardens exist, for they are familiar with the state cooperative farms only, and these produce "Standard" blacks and greens identified by number only. They are skillfully blended to guarantee stable quality whatever the climate conditions. Certain standard teas are nonetheless high quality products designed for export only: e.g., Imperial Yunnan or Imperial Keemun, like we have at the TG.

6. China's secret gardens, however, are kept distinct from these cooperatives and are called "Sacred Gardens" by the privileged few. Their exact number is unknown, possibly thirteen to fifteen. They are said to be patrolled day and night by guards and dogs. Why such secrecy? These gardens produce TINY quantities of superlative green tea that is kept off the market and is reserved exclusively for high government officials and now some has made its way here to the Tea Garden.

7. Halfway between the state and the secret/Sacred gardens, China also has gardens producing tea that can be purchased, assuming one has managed to establish a special relationship with certain authorities, like Dr. Tea has. These gardens are in remote mountainous regions; the teas are rare and very expensive. Pi-Lo, "Spiral of Spring Jade," is one of them.

8. Dragon's Well (Lung-Ching) is probably the most famous of the China greens, and that is a location in China. It is located in Chekiang province, near Hangchow's West Lake, and grows on the peaks of Tieh Mu (T-yeh Mu) mountain range. Lung Ching means: Dragon Well in Chinese. Legend tells us that the dragon is the king of the waters in Chinese mythology. History tells us that in 250 A.D., there was a drought at the Dragon's Well Monastery. A monk prayed, imploring the Dragon for rain. It rained instantly, and the tea produced there received that name.

PROCESS: FROM LEAF TO GREEN TEA
1. Tea is first plucked from the stem, two leaves and a bud.
2. Tea is then cleaned and dried and sometimes it is steamed for less than one minute in large vats. This is to kill the enzymes that cause oxidation.
3. Next it is kneaded by hand, stacked in small piles, and dried for about ten hours, during which time it is constantly turned.
4. Tea is then pan fired, and sometimes steamed to stop the oxidation process which is going on since the removal from the stem.
5. The tea is then rolled according to the desired grade.
6. Finally, the tea is sorted.

General Types of Chinese Green Teas (We will use the actual Chinese names and not the western names given by the factories who sell to the West): Remember there are too many Chinese Green Teas to discuss them all here. Dr. Tea has included some rare greens here to discuss and many are found on our TG menu.

GUNPOWDER A

Gunpowder is known by their districts: e.g., Tienkai Gunpowders, Moyune Gunpowders, Hunan Gunpowders, Fukien Gunpowders, and comes from an area in the Province south of Shanghai and north of Fujian.
B. Gunpowder is made from young to medium leaf and is subdivided into Extra First Pinhead, Pinhead, Pea leaf, First, Second, Third, Fourth, Fifth, Sixth, Seventh, and Common. The smaller the balls, the more expensive the tea. The Chinese name for Gunpowder is Siaou Chu (Small Leaf) because it opens into a full leaf during infusion.
C. Gunpowder tea is so-called because it is rolled into small balls, reminding someone of old-time gunpowder. Is all gunpowder hand rolled? It depends on the gunpowder.
i. The higher quality grades are hand rolled. Other, lower end gunpowder’s are machine rolled. However, a caveat: where labor is cheaper than machinery, it is hand rolled. How to tell the difference? The difference in flavor is remarkable. Since hand rolled generally represents a higher quality, the flavor is much more subtle, not at all harsh; very smooth foretaste and long, long delightful aftertaste. Hand rolled has a more grayish appearance and is of a smaller (pinhead) size, since it is usually composed of only the first three leaves. The higher the quality (and price), the smaller the pinhead size.
ii. Imperial Gunpowder is the largest, often 1/4 to 3/8 inch in diameter. Pinhead is actually a grading and is 3/16 to as small as 1/6 inch in diameter. The larger the size, the looser the roll. The looser the roll, the larger the leaf. The larger the leaf, the lower the leaf position on the branch.
iii. The lower the leaf position, the older the leaf. The older the leaf, the harsher the flavor. The harsher the flavor, the less expensive the tea. The less expensive the tea, the more common the tea is.
D. Gunpowder was one of the first Chinese green teas to be exported, beginning in the early seventeenth century. It enjoyed tremendous approval in Europe under the names of Hyson and Green Pearl. The USA enjoyed gunpowder comprising nearly two-thirds of all of the tea imported to the states during the Civil War.

LUNG CHING (DRAGON WELL):

Mentioned by Lu Yu himself in his book, this is one of China’s most celebrated teas. It is known for 4 distinct characteristics: green color, mellow taste, aroma, and shape. It is considered to have a cooling effect upon the body and is often served during very hot days in China
A. The finest grade is Qiqiang that has a bud and only one leaf, thus being very young and superior to the bud and two leaves. Dr. Tea was able to procure this fine and rare green tea for the TG.
B. A pound of Lung Ching contains 25,000 bud and leaf sets, each snipped off individually by well trained hands.
C. Unlike other green teas, these leaves are not hand rolled to shape the leaves and are left to their own for a more flat shape.
D. Pan firing requires a gentle touch as not to over heat the leaves in their unrolled form.

LU’AN GUAPIAN

One of China’s five best known green teas due to its unusual shape. The processed leaves are hand rolled into melon seeds and then pan fired.
E. It is of note that this tea is harvested by plucking the two leaves and bud along with the branch and then separating the tea leaves from the stem at the plantation.
F. The pan firing is done with first low, and then high heat, alternating until the desired color is obtained.

PI LO CHUN: GREEN SNAIL SPRING

Known all over the world as one of Chinas most aromatic teas. This is due to the fact that between the tea bushes they plant peach, plum, and apricot trees. These fruit trees are in full bloom as the unfolding tea leaves are at their tenderest.
G. Plucking takes place only by hand and a bud and single curled half leaf is known as the Sparrow’s Tongue. The leaf is still full of the white hairs.
H. A pound of the Pi Lo Chun contains 60,000 – 70,000 leaf bud sets.
I. Dr. Tea is in the process of obtaining some of this Chinese wonderful tea.
J. Pi Lo comes from an area north of Shanghai in the JIangsu province.

QIANGANG HUIBAI

This is a very rare tea. Originally this tea was only drank by the plantation’s owner and special friends. Now, this tea is prized by only a few and is presented at the TG by Dr. Tea.
K. This tea is made in Qianggang, a small village on Mt. Fuzhi in Zhenjiang near Pingshui home of Gunpowder.

L. The leaves are frosted with white hair on their backs and the buds are covered also with the white hairs, so fine you cannot see them.
M. The tea leaves are hand rolled into a curled shape.
N. The pan firing is done at a high temperature and covered which is very unusual and is called smothering.
O. The process is pan firing, rolling, second pan firing, and second heating in a pan which comes aglow in orange and then curing in a wooden chest after cooling and then sorting.

TAI PING HOUKUI

This tea is known as the best of Anhui Province’s pointed green teas. Dr. Tea was able to procure a fine example of this prized tea for the TG. The tea smells of orchids which grow naturally in the area and blossom at the same time as the buds are beginning to open.

P. The leaves are processed thru pan firing and the processed leaves are known for their straight, taut, and heavy character.
KOOLOO OR ANCIENT TEA
This tea is said to have been consumed for 1500 years. Its name means very old, and comes from the Guangzhou and Guangdong province.
Q. Its brew is unusual as it is brownish red in color. It has a slight burnt palate and a sweet aftertaste.
R. Pan firing after sun drying and then rolled. They are then pan fired ten times in a rolling drum carefully, to obtain the burnt flavor and color.

YOUNG HYSON

Young Hyson is made from young to medium leaves in a long, twisted style. It is thinly rolled and looks very much like twisted thread. It is subdivided into Chun Mee, Foong Mee, Saw Mee and Siftings, and sometimes into First, Second, and Third Young Hyson.
S. Chun Mee Young Hyson has a small, hard, twisted leaf.
T. Foong Mee has a large long leaf and forms a curly roll.
U. Saw Mee has a small, twisted leaf, that is not hard.
V. The Chinese name for Young Hyson is Yu Chin Ch’a and is graded into the following: Mi Yu, O Yu, I Yu, Ya Yu and Si Yu.

IMPERIAL TEA

Imperial Tea is made from older leaf left after Gunpowder is sorted. It is made in the Gunpowder style, but looser. It is sub-divided into First, Second and Third Imperial. First Imperial is a closely rolled, regular leaf. Second is a more loosely-rolled leaf and third is very large and very loose.
In Chinese, Imperial is known as Ta Chu -- "Large Leaf." The three grades are Tsang Chu, Tan Chu and Hsi Chu.

HYSON

Hyson is made from older leaves. Young Hyson - Imperial style. It is called in Chinese, Si Chuen Ch'a, meaning "Flowery Spring Tea." It is graded into Mi Si, Cheng Si and Fu Si.

TWANKEY

Twankey is an old, ragged, open leaf of inferior quality similar in nature to fannings.

HYSON SKIN

This is an even power grade.

DUST

This is what settles at the end of all sorting and used for bags.

BREWING YOUR CHINESE GREEN TEA
Chinese green teas due to the pan firing require more steep time than does the Japanese variety. It is recommended to steep your Chinese Green tea for 3- 5 minutes. Dr. Tea prefers to steep closer to 3 minutes.

Green Tea in Japan

1. The first written account of green tea in Japan was when Emperor Shomu, during the Tang Dynasty, in 729 AD, served the beverage. These leaves must have been brought by Chinese Buddhist monks on their travels to Japan.

2. Green Tea, as a product, was introduced to Japan in the seventh century. The Buddhist Monk, Saicho, in 803 A.D went to China to study Zen Buddism where he met another Japanese monk by the name of Eichu. It was in China where they were introduced to tea from Chinese monks who were drinking the beverage to assist with their daily hours of meditation.

3. The two monks returned to Japan in 805 A.D. and brought with them seeds for tea plants (Camellia Sinensis) and the knowledge of the benefits of tea and how to prepare and consume the beverage (which was prepared in cakes and broken off at that time.)

4. The seeds were eventually planted at their Buddhist monastery and within 5 years there were tea plants ready for harvest. Of course the tea of the day was green, which required little preparation compared to the oolong and black teas, and green tea was then produced for the first time in Japan.

5. The original tea ceremony started in China and was brought over by the two monks who posthumously live in fame for bringing the medicinal beverage to Japan.

6. Relations between China and Japan became strained after this and for almost 2 centuries there was no trade of information or product.

7. Around 1190 A.D., the Buddhist monk, Eisai, returned for the first time to China for studies and returned to Japan with the knowledge of how the Chinese were drinking tea in a powdered format. It was here that powdered green tea came to Japan and the resulting ceremony we know of today.

8. Eisai, was very important to Japanese tea history as he penned the fist tea book in Japan, “Notes on the Curative Effects of Tea.” He was responsible for spreading the medicinal benefits of tea to Japan and then the world. Also of note was his second book which explains the tea ceremony which we will discuss below.

9. It is important to note that during this time in history, the rule of the Emperors was in decline in favor of the military, “Samurai.” When the Samurai leader Sanemoto fell ill, the tea master Eisai was summoned to assist. He put the warrior on tea and Sanemoto was cured. From this event, tea was prescribed for many ailments and was being consumed by all in Japan.

10. Tea tasting contests began to spring up all over Japan and by the Thirteenth century there were over 100 tasting contests.

The Tea Ceremony (Cha-No-Yu)

Japanese Tea Ceremony

A. Cha No Yu means “hot water for tea”
B. This develops into the ceremony of tea. A place where time is taken for oneself, and to give honor to ones past, present and future.
C. A tea room in the home is a sign of importance and wealth. One and no more than five enter the home in preparation to enter the tea room.
i. One then takes a fan, in symbolic representation of the Samurai’s sword, and tucks it into their waist band or belt.
ii. The guests pass thru the garden which is symbolic of untying the outside world from ones being.
iii. Water trickles from a source to wash ones hands which symbolizes not only cleaning of the hands but to create the attitude of humility and removing dust from ones mind.
iv. The tea room stands two feet or so above the ground which requires guests to enter on their knees after removing their shoes, which places all of the participants at the same level regardless of rank, as tea is the celebrity and not the participants.
v. The room is small and plain which symbolizes the Bodhisattvas saying that for the truly enlightened space does not exist nor is it important.
vi. First comes a sweet, then one wet and gooey, and another dry.
vii. The hostess then begins the ceremony with the matcha powder by placing some in a mixing bowl using a long bamboo scoop. She then whips the powder into a froth with a whisk.
viii. The principal guest then accepts the first bowl and says, “Excuse me for drinking before you. I gratefully accept the tea you have prepared.” They drink and then wipe off the bowl with a napkin.
ix. The process is repeated aver a long period of time. Dr. Tea will read a chapter from a book which eloquently describes the process.

TYPES OF JAPANESE GREEN TEAS
Green tea (ryokucha) is so ubiquitous in Japan that it is more commonly known as "tea" (ocha) and even "Japanese tea" (nihoncha). Types of tea are commonly graded depending on the quality and the parts of the plant used. There are large variations in both price and quality within these broad categories, and there are many specialty green teas that fall outside this spectrum. The very best Japanese green tea is said to be that from the Uji region of Kyoto.

GYOKURO GREEN TEAS
GYOKURO means ("jewel dew") and is the highest quality Japanese green tea, Gyokuro has been called "history, philosophy and art in a single cup." For three weeks before the spring harvest, Gyokuro leaves are shaded from direct sunlight, leading to a slower maturation that enhances the leaves' content of flavenols, amino acids, sugars and other substances that provide green tea's health benefits, aroma and taste. Intensely green and sweeter than Sencha, Gyokuro leaves can serve as the base for Matcha—the silky chartreuse tea powder used to make Chanoyu, the tea of the Japanese tea ceremony. Gyokuro is regarded as the highest grade of tea made in Japan.

MATCHA means ("rubbed tea") and is used primarily in the tea ceremony. Matcha comes from Gyokuro leaves that have been steamed and dried. The tea bushes are shaded from sunlight for 3 weeks before harvesting, producing amino acids that sweeten the taste. All stems and veins are removed from the leaves. The pure dried leaves (tencha) are then stone ground into a super fine powder that is the consistency of talc. Most high quality Matcha comes from the Uji Tawara area, the premier matcha producing region in Japan. Matcha is also a popular flavour of ice cream and other sweets in Japan.

MECHA GREEN TEAS
MECHA ("bud tea") The name of this tea is derived from the early leaf buds needed to make this special green tea. Mecha is harvested in spring and made as rolled leaf teas that are graded somewhere between Gyokuro and Sencha in quality. Mecha are made from a collection of leaf buds and tips of the early crops.

SENCHA GREEN TEAS
SENCHA ("roasted tea") The most common type of green tea in Japan. It is made from the young leaves of uncovered plants. Over three quarters of all tea produced in Japanese tea gardens is Sencha. The earliest season (first month's Sencha harvest) is called Shincha. Later harvests of Sencha have more astringent qualities, a more robust flavor and generally less aroma.

SHINCHA ("new tea") A newly harvested, lightly steamed Sencha. It is aromatic but highly perishable, lasting for only about 3 months. Shincha is available in April in the south of Japan, and prized for its high vitamin content, sweetness, and superior flavor.

GENMAICHA ("roasted rice tea") A blend of Bancha green tea and genmai (roasted rice grain). The flavor is a mélange of these two ingredients. The roasted aroma of Genmai teas has the effect of lightening the bitterness of the lower grade Sencha. The proportioning of tea to rice is important, the more aromatic Genmai teas have a higher amount of rice.

KABUSECHA ("covered tea") Unlike most Sencha cultivated in unshaded gardens exposed to direct sunlight, Kabusecha sencha requires shading tea prior to harvest. Kabusecha sencha has a mellower flavor and more subtle color than Sencha grown in direct sunlight.

KAMAIRICHA ("pan fired tea") Kamairi teas do not undergo the usual steam treatments. After a short withering, they are fired in hot iron pans of up to 300°C with repeated agitation to prevent charring. The different rolling techniques used produce teas of different leaf form. Kamairicha is processed as a pelleted or flat leaf.

BANCHA GREEN TEAS
BANCHA ("number or common tea") is a class of Sencha that is harvested as a second flush tea between summer and autumn. While lacking the delicate sweetness of quality Sencha it is respected for its well-defined character, vivid yellow colors and refreshing and deep flavors. Bancha's meaning references the coarser grades and heavier, late season crop from which this full-flavoured tea is made. It is milder, cheaper and contains less caffeine than other varieties.

HOJICHA ("roasted tea") A pan-fried or oven roasted green tea commonly found in teashops throughout Japan. Both Bancha and Kukicha are used to make Hojicha grades. Hojicha tends to be a more aromatic tea. It holds very little astringency, has a distinctively clear red appearance and is lower in caffeine.

KUKICHA GREEN TEAS
KUKICHA ("stalk tea") A tea made from stalks produced by harvesting one bud and three leaves. The combined stalk fractions and emerald leaf of Gyokuro and Sencha blends are then processed. Kukicha is known for its light flavor and fresh green aroma with a very light yellow-green color. The best Kukicha has a flavor considered to be as good as highest quality Sencha. It contains only a tenth of the caffeine of leaf tea and its flavor is commonly compared to oolong teas

OTHER GREEN TEAS
Mediocre quality tea is often produced to resemble the lower grades of Chinese or Japanese tea in appearance outside those countries, however there are some notable teas grown outside China and Japan.
• Green Tea from Ceylon
• Green Tea from Darjeeling
• Green Tea from Vietnam
• Green Tea from Assam

Brewing the Perfect pot of Green Tea: Remember Dr. Tea always recommends covering the bottom of your vessel with a thin line of tea after preheating your vessel. Below please find some useful tips from the Japanese experts.

A. Green tea should be handled tenderly, just as you would fresh green leafy vegetables.

B. Spring water is the ideal choice for brewing tea, followed by filtered water. Distilled water should never be used; the brew it produces will be flat since the minerals removed from it are essential to bringing out tea's flavor.

C. To prepare the best loose tea, we recommend using a small food scale. Use three grams of tea to five ounces of water if brewing tea in a small teapot; four grams of tea to eight ounces of water for other methods.

D. In making loose tea, remember that a teaspoon of small, dense leaves will weigh substantially more than a teaspoon of larger leaves, and the resulting tea will reflect this. A teaspoon of small dense leaves may be sufficient to produce a satisfying strong cup, while several teaspoons of larger leaves would be needed for a comparable brew.

E. Although heartily boiling water can be used to brew black and oolong teas, green tea needs much lower temperatures (160-170 degrees F; 79-85 degrees C) and should be brewed for less time.

F. Let the water barely reach the boiling point to liberate its oxygen, then allow it to cool slightly before pouring over your tea. Until you are familiar with your tea kettle and the time it takes and sounds it makes when the correct temperature (170-185 degrees) has been reached, it's a good idea to check using a simple, inexpensive candy thermometer, available at any grocery store.

G. Brewing for 30 seconds to one minute is usually ideal; however, Nilgiri and Darjeeling greens can take several minutes, and Chinese Dragonwell teas are often best after 6-7 minutes of infusion due to the pan firing techniques to produce the tea.

H. Although good quality tea leaves will sink to the bottom after they have infused, it's a good idea to pour the tea over a small strainer if one is not built in to your teapot.

HOW THE JAPANESE MIX GREEN TEA TO THEIR FOODS
A. Brew green tea with thinly sliced ginger and lemon, or sprigs of spearmint. Add one teaspoon of honey per cup, stir and serve hot or use half the amount of hot water (or twice the amount of tea), allow the tea to brew and cool, then pour over ice cubes.
B. Make a green tea chai by brewing green tea in hot vanilla soy milk and topping with a dash each of cinnamon, black pepper, ginger and allspice.
C. Brew 1-2 teaspoons loose leaf green tea in 8 ounces cool water for 20-30 minutes to develop flavor without bitterness and add to stir-fries, marinades, dressings, soups and sauces.
D. Sprinkle Gyokuro tea over a salad, stew or rice dish.
E. Add ½ teaspoon Gyokuro tea to an almost set omelet or scrambled eggs.
F. Add crushed Chinese Gunpowder tea and rice vinegar to sesame oil for delicious vinaigrette.
G. Mix Gyokuro tea with sesame seeds and sea salt and use to dredge shrimp or fish filets before lightly pan-frying them.
H. Cook Japanese udon noodles in green tea for about 5 minutes, then remove from heat and leave noodles in tea until cool. Drain and toss lightly with soy sauce and sesame oil. Add thinly sliced tofu, scallions, mushrooms, and chopped cilantro, and serve.
I. Poach Asian or Bosc pears in green tea with fresh thinly sliced gingerroot. Drizzle with honey and top with a sprig of fresh mint.
J. Combine cooled green tea half and half with a fruit juice, such as peach, pineapple or papaya. Sweeten with a teaspoon of honey per cup. Blend and pour over ice.

HEALTH BENEFITS OF GREEN TEA

Dr. Tea has researched this topic and has found a very comprehensive article and presents it below. Please contact your MD directly regarding any of these issues as they relate to your health as Dr. Tea is in fact not an MD, but a mere Tea Expert.

Green tea is particularly rich in health-promoting flavonoids (which account for 30% of the dry weight of a leaf), including catechins and their derivatives. The most abundant catechin in green tea is epigallocatechin-3-gallate (EGCG), which is thought to play a pivotal role in the green tea's anticancer and antioxidant effects. Catechins have been found to be more potent free radical scavengers than the well known antioxidants vitamins E and C.

Most of the research showing the health benefits of green tea is based on the amount of green tea typically consumed in Asian countries—about 3 cups per day (which would provide 240–320 mg of polyphenols). Just one cup of green tea supplies 20-35 mg of EGCG, which has the highest antioxidant activity of all the green tea catechins.

The health benefits of green tea have been extensively researched and, as the scientific community's awareness of its potential benefits has increased, so have the number of new studies. As of November 2004, the PubMed database contained more than 1,000 studies on green tea, with more than 400 published in 2004! Following is a brief summary of some of the high points of this most current research.

Green tea drinkers appear to have lower risk for a wide range of diseases, from simple bacterial or viral infections to chronic degenerative conditions including cardiovascular disease, cancer, stroke, periodontal disease, and osteoporosis. The latest studies provide a deeper understanding of the ways in which green tea:

Protects against Coronary Artery Disease
In Japanese studies, green tea consumption has been found to be an independent predictor for risk of coronary artery disease. In one study, those drinking 5 or more cups of green tea each day were found to be 16% less likely to suffer from coronary artery disease. The relationship was so significant researchers concluded, "The more green tea patients consume the less likely they are to have coronary artery disease."

An elevation in the amount of free radicals in the arteries is a key event in many forms of cardiovascular disease. The latest research shows that green tea catechins inhibit the enzymes involved in the production of free radicals in the endothelial lining of the arteries. The arterial endothelium is a one-cell thick lining that serves as the interface between the bloodstream and the wall of the artery where plaques can form. By protecting the endothelium from free radical damage, green tea catechins help prevent the development of cardiovascular disease.

Inhibits Atherosclerosis
Green tea has been shown to effectively lower risk of atherosclerosis by lowering LDL cholesterol, triglycerides, lipid peroxides (free radicals that damage LDL cholesterol and other lipids or fats) and fibrinogen (a protein in the blood involved in the formation of blood clots), while improving the ratio of LDL (bad) to HDL (good) cholesterol. In animal studies in which green tea was given in human equivalent doses to hamsters, atherosclerosis was inhibited 26-46% in those receiving the lower dose (equivalent in humans to 3-4 cups per day) , and 48-63% in those receiving the higher dose (10 cups a day in humans).

Special Benefits for Persons with High Triglycerides
Green tea may offer special heart-protective benefits for persons with high triglycerides, suggests a laboratory study, published in the February 2005 issue of the Journal of Nutrition.

A series of experiments revealed that the mix of catechins naturally found in green tea dose-dependently inhibit the activity of pancreatic lipase, the enzyme secreted by the pancreas that digests fat. As a result, the rate at which the body breaks down of fats into triglycerides, and the rise of triglyceride levels in the bloodstream that occurs after meals, is greatly slowed. Since a large rise in blood levels of triglycerides after a meal is a significant risk factor for coronary heart disease, drinking a cup of two green tea along with your meals is a good idea, especially if your triglyceride levels are higher than normal.

Thins the Blood and Helps Prevent Blood Clots
Green tea catechins help thin the blood and prevent the formation of blood clots by preventing the formation of pro-inflammatory compounds derived from omega-6 fatty acids, which are found in meats and polyunsaturated vegetable oils such as corn, safflower and soy oil. These pro-inflammatory compounds—specifically, arachidonic acid from which the inflammatory cytokines thromboxane A2 and prostaglandin D2 are derived—cause platelets to clump together.

Protects the Heart in Patients with Acute Cardiovascular Disease
The primary catechin in green tea, EGCG (epigallocatechin-3-gallate) confers such powerful protection that it can help prevent the death of heart muscle cells following ischemia/reperfusion injury. Ischemia is the medical term for a restriction in blood supply and therefore in oxygen and nutrients. When circulation is restored, oxidative damage occurs, and this is referred to as reperfusion injury. EGCG prevents heart muscle damage by blocking the activation of inflammation-related compounds (including NF-kappa-B and STAT-1) that play a critical role in promoting the oxidative damage that kills heart cells in reperfusion injury. Researchers believe EGCG can be used to help minimize damage in patients with acute coronary artery disease.

Minimizes Damage and Speeds Recovery after a Heart Attack
Research conducted over the last several years by Dr. Anastasis Stephanou and his team at the UK's Institute of Child Health and published in the FASEB Journal, the journal of the Federation of Experimental Biology and the Journal of Cellular and Molecular Medicine has focused on EGCG's ability to block the action of the protein, STAT-1. Normally activated in cells after a heart attack or stroke, STAT-1 plays a major role in inducing cell death.

Not only does green tea minimize heart cell death after a heart attack or stroke, ECGC also appears to speed up heart cells' recovery from damage, allowing the tissues to recover more quickly and alleviating damage to organs. Dr. Stephanou, a molecular biologist, noted: "We're extremely encouraged by these findings and hope to implement them in the clinical setting to minimize cell death activation in patients with acute coronary heart disease."

Minimizes Damage to the Brain after a Stroke
EGCG has also been shown to protect brain cells by these same mechanisms and thus may help minimize the brain damage that occurs after a stroke. In one animal study, green tea was so effective in reducing the formation of free radicals in brain tissue that the researchers concluded, "Daily intake of green tea catechins efficiently protects the brain from irreversible damage due to cerebral ischemia, and consequent neurologic deficits."

Lowers Blood Pressure and Helps Prevent Hypertension
A study published in the July 2004 issue of the Archives of Internal Medicine found that among persons consuming tea regularly for at least one year, the risk of developing high blood pressure was 46% lower among those who drank ½ cup to 2 ½ cups per day, and 65% less among those consuming more than 2 ½ cups per day.

In another study, this one of rats bred not only have high blood pressure but also to be prone to strokes, those rats given green tea had significantly lower systolic and diastolic blood pressure compared to controls, who received plain water. The animals in this study, which was published in the January 2004 issue of the Journal of Nutrition, consumed the human equivalent of 1 liter (1.1 quarts or a little more than 4 cups) of green tea per day.

Helps Prevent the Development of Atherosclerosis and Cancer
In both atherosclerosis and cancer, cell growth and proliferation is central to the disease process. In atherosclerosis, plaques form in the lining of the arteries, which grow thicker and less elastic, impeding blood flow. In cancer, normal brakes on cells turn off, and they multiply out of control. Green tea can help stop abnormal cell proliferation.

Catechins, among the main active compounds in green tea leaves, shut down the primary relay station through which growth factors central to both atherosclerosis and cancer send their messages for growth. These relay stations, called tyrosine kinase receptors, are essential for the transmission of messages sent by platelet derived growth factor, insulin-like growth factor, epidermal growth factor, fibroblast growth factor, and vascular endothelial growth factor. The result is the prevention of or halting of the disease processes that depend upon excessive cellular growth.

Two other damaging factors that cause the cells lining our vasculature to proliferate are AGEs (advanced glycation end products) and MAPK (mitogen-activated protein kinase). AGEs form when sugars inappropriately bind to and distort proteins. MAPK activity is normally enhanced in the presence of elevated levels of LDL cholesterol. In laboratory studies, green tea polyphenols were shown to dose-dependently inhibit AGE-stimulated proliferation of vascular smooth muscle cells and to prevent the increase in MAPK normally seen when LDL levels are high.

Protects against Cancer
In the last ten years, green tea's cancer-preventive effects have been widely supported by epidemiological, cell culture, animal and clinical studies. For cancer prevention, the evidence is so overwhelming that the Chemoprevention Branch of the National Cancer Institute has initiated a plan for developing tea compounds as cancer-chemopreventive agents in human trials.

When confronted with a cancerous cell, green tea becomes the plant kingdom's Arnold Schwarzenegger, helping to terminate cancer cells in a remarkable number of ways.

Laboratory cell culture studies show that green tea polyphenols are powerful triggers of apoptosis (cell suicide) and cell cycle arrest in cancerous but not in normal cells. (Cell cycling is the process cells go through to divide and replicate.)

These anticancer actions have been assumed to be due to the powerful antioxidant effects of green tea's catechins, especially epigallocatechin-3-gallate (EGCG). This is a reasonable assumption, given that a number of studies have shown that green tea possesses remarkable antioxidant properties. In one study published in the November 2004 issue of Mutation Research, EGCG's protective antioxidant effects against several carcinogens were found to be 120% stronger than those of vitamin C.

But while green tea's antioxidant prowess is impressive, recent studies show it is far from the only way in which this multi-talented beverage protects us against cancer.

One of these mechanisms is green tea's ability to inhibit angiogenesis, the development of new blood vessels. Cancer cells, which are constantly attempting to divide and spread, have an endless appetite that can only be temporarily quieted by increasing the number of blood vessels that supply them with nutrients. By inhibiting angiogenesis, green tea helps starve cancer.

Studies also show that green tea works at the genetic level, shutting off genes in cancerous cells that are involved in cell growth, while turning on those that instruct the cancer cells to self-destruct. EGCG has even been found to work as a pro-oxidant or free radical, but just inside cancer cells, where it causes so much damage that the cancer cells' self-destruct mechanisms are triggered.

A study of ECGC's effects on keratinocytes (the major type of epidermal or skin cell) found that this green tea compound has yet another means of correcting cancer—that of turning on the genes that direct the cancer cell to return to normal.

Green tea's anticancer effects include its ability to inhibit the overproduction of the enzyme cyclooxygenase (COX)-2, a protein whose overproduction has been implicated as a factor in many diseases, including arthritis and cancer. COX-2 has an enzyme counterpart, called COX-1, which may be helpful to leave untouched when preventing overproduction of COX-2. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen (which inhibit both COX-1 as well as COX-2), and specific COX-2 inhibitors such as Vioxx and Celebrex (which inhibit only COX-2), have been considered as possible agents in the prevention of some forms of cancer, but their severe toxic side effects on normal cells limit their usefulness. In studies of prostate cancer cells, EGCG appears to block only COX-2 and to have no negative side effects.

Prostate Cancer
EGCG provides other benefits specific to prostate cancer prevention. A study published in the December 2004 issue of the International Journal of Cancer found that EGCG significantly inhibited, in a dose-dependent manner, the production of prostate-specific antigen (PSA), a marker for prostate cancer risk. Not only did EGCG lower PSA levels, but it also suppressed all the activities of PSA which were examined that promote prostate cancer.

Green tea polyphenols halt prostate cancer at multiple levels
The polyphenols in green tea help prevent the spread of prostate cancer by mobilizing several molecular pathways that shut down the proliferation and spread of tumor cells, while also inhibiting the growth of blood vessels that supply the cancer with nourishment, according to research published in the December 2004 issue of Cancer Research.

Green tea polyphenols:

decrease insulin-like growth factor-1 (IGF-1), while increasing levels of IGF binding protein-3, which binds IGF-1, further diminishing its activity. (Increased levels of IGF-1 are associated not only with prostate cancer, but cancers of the breast, lung and colon.)
inhibit key cell survival proteins, promoting apoptosis or programmed cell death in cancer cells.
reduce the expression of several compounds (urokinase plasminogen activator and matrix metalloproteinase 2 and 9) involved in the metastasis and spread of cancer cells.
reduce the amount of vascular endothelial growth factor (VEGF), which develops new blood vessels to carry nutrients to developing tumors.
All these effects were seen in this animal study within 6 months of continuous infusion. While obviously impractical for humans, the study suggests that daily consumption of green tea may be highly protective.

Ovarian Cancer
Green tea consumption has been shown to enhance survival in women with ovarian cancer. In a study published in the November 2004 issue of the International Journal of Cancer, women with ovarian cancer who drank at least 1 cup of green tea daily had a 56% lowered risk of death during the 3 years of the study compared to non-tea drinkers. A laboratory study of human ovarian cancer cells published in the September 2004 issue of Gynecologic Oncology explains why: EGCG not only suppresses the growth of ovarian cancer cells, but also induces apoptosis (cell suicide) in these cells by affecting a number of genes and proteins.

An epidemiological (population) study published in the December 2005 issue of the Archives of Internal Medicine, adds more evidence that enjoying a cup or two of tea each day may significantly lower a woman's risk of ovarian cancer.

Data from numerous other studies has suggested that both green and black tea may offer protection against various cancers, with tea polyphenols thought to be the most likely protective agents. In this research, Susanna Larsson and Alicja Wolk from the National Institute of Environmental Medicine, Stockholm, Sweden, decided to look specifically at the relationship between tea consumption and ovarian cancer.

Participants in their study were 61,057 Swedish women aged 40-76 years who were in the Swedish mammography cohort and had completed a validated 67 item food frequency questionnaire at baseline (between 1987-1990), after which the women were followed an average of 15.1 years.

Analysis of the data found that even women who averaged less than one cup of tea per day had an 18% lower risk of ovarian cancer than non-tea-drinkers.

Those who drank one cup per day had a 24% lower risk, and those who drank two or more cups of tea per day had a 46% lower risk of ovarian cancer than non-tea-drinkers.

Each additional cup of tea per day was associated with an 18% lower risk of ovarian cancer. Although higher tea consumption was generally associated with other health-promoting behaviors, including higher consumption of fruits and vegetables, when compared to the lifestyle behaviors of those who seldom or never drank tea, the large drop in ovarian cancer risk seen as tea consumption increased does suggest that tea is likely to offer significant protection.

Breast Cancer
Recent studies have also identified two mechanisms through which green tea works against breast cancer. Not only does EGCG inhibit the activity of telomerase, an enzyme that plays a key role in cell division, in breast cancer cells, but it also offers help to women with estrogen-negative breast cancer, a form of breast cancer that is very hard to treat successfully.

Estrogen-negative breast cancer cells express high amounts of the epidermal growth factor Her-2/neu, while in the more treatable estrogen-positive form of breast cancer, estrogen-receptor alpha (ERalpha) is expressed. According to a study published in the October 2004 issue of Molecular and Cellular Biology, EGCG induces the expression of ERalpha rather than Her-2/neu in breast cancer cells.

Brain Tumors in Children
Green tea's ability to inhibit telomerase may also translate into help for children with the most common malignant brain tumors of childhood, primitive neuroectodermal tumors. Telomerase's activity allows cancer cells to avoid the normal limits on the number of times a cell can replicate before it self-destructs. In a study published in the January 2004 issue of Neuro-oncology, investigators found that telomerase activity was at least five times higher in children with these brain tumors than in normal brain cells and that EGCG strongly inhibited telomerase activity in a dose-dependent manner.

Colon Cancer
Green tea may also reduce the increased risk for colon cancer caused by a high fat diet. An animal study published in the journal Nutrition and Cancer in 2003 found that when green tea was given along with a diet high in omega 6 fat (in the form of corn oil), the amount of pro-inflammatory compounds produced in the colon (5-lipoxygenase, leukotriene A4 hydrolase, and leukotriene B4) was significantly lower, as was the resulting number of precancerous colon cells (aberrant crypt foci). Green tea consumption even reduced the amount of abdominal fat produced in the animals that received it compared to controls.

Lung Cancer
While we certainly do not recommend smoking, if you or someone you love smokes, or if you must be around smokers and are exposed to second hand smoke, drinking green tea can offer some protection against lung cancer. A human pilot study recently confirmed the protective effects of green tea against lung cancer seen in cell culture and animal studies. The study, published in the November 2004 issue of Molecular Nutrition and Food Research evaluated the effect of green tea (5 cups per day) on 3 heavy smokers (>10 cigarettes a day) and 3 individuals who had never smoked. When the study subjects were drinking green tea, DNA damage caused by smoking was decreased, cell growth was inhibited, and cellular triggers for apoptosis (cell suicide) in abnormal cells increased.

Another larger four month study of heavy smokers involving 100 women and 33 men found that levels of urinary 8-hydroxydeoxyguanosine, a marker of free radical damage to DNA, dropped significantly in individuals drinking decaffeinated green but not black tea. Decaffeinated green tea was especially effective in reducing DNA damage in individuals who lack the genetic ability to produce normal amounts of an enzyme called glutathione S-transferase, which plays a key role in the liver's ability to detoxify many of the carcinogens found in cigarette smoke. Individuals whose genetic inheritance does not include the GSTM1 and GSTT1 variants of the genes that instruct the cell to produce glutathione S-transferase are more susceptible to developing many different cancers. For these individuals, green tea may be especially beneficial.

Bladder Cancer
Research by a multi-departmental team from UCLA has produced valuable insights into how green tea extract might be capable of acting against the invasive growth of bladder cancer tumors. Green tea extract has been shown, via a mechanism that affects cell movement, to target cancer cells while leaving healthy cells alone.

For cancer to grow and spread, the malignant cells must be able to move, and their movement depends on a process called actin remodeling, which itself is carefully regulated by complex signaling pathways, including the Rho pathway.

By inducing Rho signaling, green tea causes cancer cells to mature more rapidly and to bind together more closely, a process called cell adhesion. Both their increased maturity and cell adhesion inhibit cancer cells' mobility, according to Rao, senior author of the study, published in the February 2005 issue of Clinical Cancer Research, in which green tea's effects on Rho signaling were noted.

"Cancer cells are invasive and green tea extract interrupts the invasive process of the cancer…In effect, the green tea extract may keep the cancer cells confined and localized, where they are easier to treat and the prognosis is better," explained Rao.

About 56,000 new cases of bladder cancer are diagnosed each year, making it the fifth most common cancer in the United States. About half of all bladder cancers are believed to be related to cigarette smoking. Bladder cancer can be difficult to detect in the early, most treatable stages, yet, when not found early, the tumors can be aggressive, and more than half of patients with advanced cancers experience recurrences. In the next phase of his research, Rao and his team will analyze urine from bladder patients, looking particularly for biomarkers associated with actin remodelling and the activation of the Rho pathway, to determine which subset of patients might benefit most from green tea.

Improves the Efficacy of Cancer Drugs While Lessening Their Negative Side-Effects
In the fight against cancer, green tea polyphenols are team players, helping cancer-killing drugs do their job. In a study published in the October 2004 issue of the Journal of Pharmacy and Pharmacology, green tea polyphenols caused drug-resistant cancer cells, which were able to extrude or push out one of the most commonly used cancer drugs, doxorubicin, to retain the drug, which could then destroy them. According to a study published in the August 2004 issue of Cancer Letters, another compound in green tea, the amino acid theanine, reduces the negative side effects of doxorubicin by increasing the level of one of the body's most important internally produced antioxidants, glutathione, in normal tissues in the liver and heart—but not in tumors.

Understanding How Green Tea Fights Cancer
Spanish and British scientists have discovered at least one of the mechanisms through which green tea helps to prevent certain types of cancer, according to a study published in the March 2005 issue of Cancer Research.

ECGC, a catechin present in green tea in amounts about 5 times higher than in black tea, inhibits the enzyme dihydrofolate reductase (DHFR), which cancer cells need to be able to grow, and which is a well recognized target of anti-cancer drugs.

Scientists decided to look at ECGC after they realized the green tea catechin looks a lot like the cancer drug methotrexate, which prevents cancer cells from making DNA by inhibiting the DHFR enzyme. They discovered that ECGC kills cancer cells in the same way as the drug.

Although ECGC binds strongly to DHFR, which is essential in both healthy and cancerous cells, it does not bind as tightly as methotrexate, so its side effects on healthy cells are less severe than those of the drug.

ECGC's binding to DHFR may also explain why women who drink large amounts of green tea around the time they conceive and early in their pregnancy may have an increased risk of having a child with spina bifida or other neural tube disorders.

Women are advised to take supplements of folic acid when trying to conceive and during the first trimester (the first 3 months) of pregnancy because it is during this time period that the baby's neural tube is developing. Folic acid helps ensure normal development and protects against spina bifida by enabling the production of the enzyme DHFR. While a cup or two of green tea is unlikely to pose a problem, drinking large amounts of green tea could decrease the activity of DHFR, increasing risk of neural tube defects.

Improves Insulin Sensitivity in Type 2 Diabetes
Population studies suggest that green tea consumption may help prevent type 2 diabetes. A number of animal studies are beginning to explain why. New studies suggest that green tea may improve glucose tolerance and insulin sensitivity in individuals with diabetes. In one study, after receiving green tea for 12 weeks, diabetic rats had lower fasting blood levels of glucose, insulin, triglycerides and free fatty acids compared to controls, and the ability of their adiopcytes (fat cells) to respond to insulin and absorb blood sugar greatly increased.

In another study by the same research group, diabetic rats were separated into three groups and followed for 12 weeks. One group was given with standard rat chow and water (the control group), the second group received a high fructose diet and water (fructose group), and the third group got the same high fructose diet and green tea (green tea group). By the end of the study, the fructose group had high blood sugar, high insulin levels, and high blood pressure, while the animals receiving green tea along with a high fructose diet showed improvement in all three.

A study published in the August 2004 issue of BMC Pharmacology, in which oral glucose tolerance tests were given to healthy humans after they consumed green tea, showed that it increased the body's ability to utilize blood sugar.

Another interesting animal study compared the effects of a Western diet, a vegetarian diet and a Japanese diet, each with or without green tea. Blood sugar concentrations were highest in the animals on the Western diet followed by the Vegetarian diet with the Japanese diet producing the lowest blood sugars. When supplemented with green tea, blood sugar levels dropped in rats on all three diets, with those on the Japanese diet having not only the lowest blood sugars but also rating the best on other risk factors for type 2 diabetes. Rats on the Japanese diet that also were given green tea had the lowest triglycerides and cholesterol as well as the highest ratio of beneficial omega-3 fatty acids to potentially inflammatory omega-6 fatty acids. The researchers concluded that Japanese eating habits combined with drinking green tea might help prevent type 2 diabetes.

One of the mechanisms through which green tea improves insulin sensitivity has recently been identified in laboratory studies that show that epigallocatechin 3-gallate (EGCG) does a good deal more to prevent type 2 diabetes than lower the production of free radicals. EGCG also works on the genetic level, causing a reduction in the number of messenger RNAs that direct liver cells to produce the enzymes involved in the creation of glucose (sugar).

Protects against Kidney Disease
An animal study published in the January 2005 issue of Pharmacological Research suggests yet another beneficial effect of green tea consumption: the prevention of kidney dysfunction in persons who must take powerful immunosuppressant drugs, for example, after an organ transplant.

One such drug, cyclosporine A, while a very effective immunosuppressant, also markedly elevates the production of free radicals highly toxic to the kidneys. In this study, rats given green tea as their drinking water along with cyclosporine A produced far fewer damaging free radicals than rats given plain water. In addition, a number of other indicators of kidney function (serum creatinine, blood urea nitrogen, uric acid and urinary excretion of glucose) were significantly better in rats given green tea.

Another animal study published in May 2004 in the Annals of Nutrition & Metabolism explains why. Diabetic rats given green tea catechins and then exposed to a kidney-damaging drug, streptozotocin, produced less than half the amount of superoxide radicals (a particularly damaging type of free radical) compared to diabetic rats on a catechin-free diet. As a result, a cellular waste product formed by free radical damage to fats, lipofuscin, was almost 200% higher in the diabetic rats who did not receive green tea catechins compared to those who did.

Prevents Osteoporosis and Periodontal diseases
Excessive bone loss is a characteristic feature not only of osteoporosis but of periodontal disease. Green tea supports healthy bones and teeth both by protecting osteoblasts (the cells responsible for building bone) from destruction by free radicals, and by inhibiting the formation of osteoclasts (the cells that break down bone).

Another benefit of green tea consumption for those with periodontal disease: green tea short circuits the damaging effects of the bacteria most responsible for gum disease, Porphyromonas gingivalis. P. gingivalis causes gum damage by producing toxic byproducts such as phenylacetic acid and by stimulating the activity and production of enzymes called metalloproteinases (MMPs), which destroy both the mineral and organic constituents that make up the matrix of our bones. Epigallocatechin-3-gallate (EGCG) inhibits P. gingivalis' production of both phenylacetic acid and MMPs.

Protects the Liver from Alcohol and Other Harmful Chemicals
Alcohol metabolism results in the production of damaging free radicals that can overwhelm the liver's supply of antioxidants, resulting in liver injury. In a study published in the January 2004 issue of Alcohol in which rats were chronically intoxicated with alcohol for 4 weeks, green tea prevented damage to their livers.

Other animal research shows that epigallocatechin-3-gallate (EGCG) protects the liver against the free radicals generated when mice are exposed to carbon tetrachloride, a toxic chemical solvent. Without the protection afforded by EGCG, carbon tetrachloride exposure resulted in the production of numerous free radicals that destroyed a significant amount of the animals' liver cells. With EGCG, free radical production and liver injury was so greatly reduced that researchers suggested green tea should be used in the treatment of liver disease.

Unlike some herbs, green tea's protective effects do not appear to affect two of the liver enzymes most often responsible for detoxifying and eliminating drugs, cytochrome P-450 2D6 and 3A4. This suggests that green tea might be safely consumed when taking medications primarily dependent upon the CYP2D6 or CYP3A4 pathways of metabolism. Hopefully, future research studies will bear out this potential benefit.

On the other hand, one study found that Japanese green tea did increase the activity of the CYP1A1 enzyme. Researchers hypothesized that the increase in activity of this liver enzyme may be one of the ways in which green tea helps protect against cancers caused by various dietary carcinogens.

Promotes Fat Loss
Green tea not only promotes fat loss, but specifically, the loss of visceral fat—fat that accumulates in the tissues lining the abdominal cavity and surrounding the intestines (viscera) and internal organs. Unlike fat deposits on the hips and thighs (which result in the so-called "pear" body shape), visceral fat (which produces the "apple" body shape) is highly associated with increased risk for metabolic syndrome and type 2 diabetes. Green tea contains three major components that promote fat loss: catechins, caffeine and theanine. Studies suggest that green tea compounds promote fat loss by inhibiting both gastric and pancreatic lipase, the enzymes that digest triglycerides, and fatty acid synthetase, the enzyme responsible for synthesizing fatty acids into the form in which they can be stored in the body's adipose (fat) cells.

In a study published in the January 2004 issue of In Vivo in which mice were fed diets containing 2% green tea powder for 16 weeks, visceral fat decreased by 76.8% in those receiving green tea compared to the control group. Green tea also decreased blood levels of triglycerides (the chemical form in which most fats exist in the body).

A human study, published in the January 2005 issue of the American Journal of Clinical Nutrition, confirms green tea's ability to not only reduce body fat, but damage to LDL cholesterol as well. After 12 weeks of drinking just one bottle of green tea each day, 38 normal-to-overweight men in Tokyo had a significantly lower body weight, BMI, waist circumference, body fat mass and amount of subcutaneous fat compared to men given a bottle of oolong tea each day.

After a 2 week diet run-in period, the men were divided into two groups, one of which drank a bottle of green tea containing 690 mg of catechins, while the other group drank a bottle of oolong tea containing 22 mg catechins.

Not only did the men drinking green tea lose weight and fat, but the amount of their LDL cholesterol damaged by free radicals also dropped significantly. Since atherosclerotic plaques develop when cholesterol circulating in the bloodstream is damaged or oxidized, green tea's ability to prevent these oxidation reactions may explain some of its protective effects against cardiovascular diseases.

Increases Exercise Endurance
Green tea extract given to lab rats over a 10-week span increased the amount of time the animals could swim before becoming exhausted by as much as 24%.

Green tea's catechins appear to stimulate the use of fatty acids by liver and muscle cells. In muscle cells, the ability to burn more fat translates into a reduction in the rate at which glycogen, the form in which carbohydrates are stored for ready access in muscle, is used up, thus allowing for longer exercise times. Green tea's effect on muscle cells' ability to take in and burn fatty acids, speeding up fat breakdown, is also thought to be the reason why it helps weight loss.

The idea for the experiment came from the fact that skeletal muscles utilize carbohydrates, lipids (fats) and amino acids (protein) as energy sources, but the ratio in which they are used varies with the intensity and type of the exercise, and the level of the individual's fitness. During endurance exercise, the use of too much carbohydrate is undesirable because it triggers insulin secretion, which, in turn, both inhibits the burning of fatty acids and stimulates lactic acid production. (Lactic acid buildup is what causes that sore achy feeling in your muscles when you exercise.) Conversely, enhanced availability and utilization of free fatty acids reduces carbohydrate utilization, which in turn spares glycogen (the form in which carbohydrates are stored in muscle for quick use) and suppresses lactic acid production, resulting in an increase in endurance."

Drinking a single cup of green tea before exercise, however, will not be effective. One single, higher "dose" of green tea did nothing to improve lab rats' performance. The animals had to receive green tea daily, and endurance increased gradually over the 10 weeks of the study. To match the beneficial effect on test animals' endurance capacity seen in the experiments, the researchers estimate a 165-pound athlete would need to drink about 4 cups of green tea daily.

Protects against Cognitive Decline, Alzheimer's Disease and Parkinson's Disease
Damage to brain cells in Parkinson's, Alzheimer's and other neurodegenerative diseases seems to result from the combination of a number of damaging factors including excessive inflammation and increased levels of iron, both of which lead to increased free radical production, exhaust the brain's supply of protective antioxidants and trigger the production of certain proteins, such as amyloid-beta, which promote apoptosis (cell suicide).

Green tea catechins, until recently thought to work simply as antioxidants, are now known to invoke a wide spectrum of neuroprotective cellular mechanisms. These include iron chelation, scavenging of free radicals, activation of survival genes and cell signaling pathways, and regulation of mitochondrial function. (The mitochondria are the energy production factories inside our cells. When they are not working properly, they generate many free radicals and little energy.) The end result is a significant lessening of damage to brain cells.

Iron accumulation in specific brain areas and free radical damage to brain cells are considered the major damaging factors responsible for a wide range of neurodegenerative disorders including both Parkinson's and Alzheimer's disease.

In the brain, epigallocatechin-3-gallate (EGCG) has been shown to act as an iron chelator, binding to and removing iron, thus preventing it from contributing to the production of free radicals. In addition to removing iron, EGCG also increases the activity of two major antioxidant enzymes, superoxide dismutase (SOD) and catalase, further helping to decrease free radical damage.

Another active compound in green tea, epicatechin (EC), reduces the formation of a protein called amyloid-beta. Plaque-like deposits of amyloid-beta in the brain are a defining characteristic of Alzheimer's disease.

Green tea polyphenols have also demonstrated the ability to affect cell signaling pathways, in particular the MAPK pathways, which are triggered by oxidative stress (free radicals), and themselves set in motion a series of chemical reactions so damaging that they can result in brain cell death. MAPK signaling pathways inside brain cells are thought to play a critical role in neurodegenerative diseases. Another important cell signaling pathway beneficially affected by EGCG, the PKC pathway, is also thought to play an essential role in the regulation of cell survival and programmed cell death.

Although no human studies on Alzheimer's disease have yet reported benefit from tea consumption, recent population studies have shown that simply consuming 2 or more cups of green tea daily reduces risk of cognitive decline and Parkinson's disease.

Green Tea Keeps Elders Mentally Sharp: Research Showing Multiple Ways

Green tea helps slow the age-related decline in brain function seen as declining memory, cognitive impairment, dementia and Alzheimer's, shows a human study published in the February 2006 issue of the American Journal of Clinical Nutrition.

Researchers at Japan's Tohoku University studied 1003 subjects over age 70, comparing their green tea intake and mental sharpness, using a Mini-Mental State Examination, a well-accepted standardized test for measuring cognitive function.

Drinking more than 2 cups a day of green tea slashed odds of cognitive impairment in elderly Japanese men and women by 64%! And a Japanese cup of green tea is much smaller than its American counterpart—only about 3.2 fluid ounces.

And at every level of cognitive impairment—from minimal to severe—those drinking the most green tea experienced significantly less mental decline than those drinking the least:

Compared with elderly Japanese who drank less than 3 cups a week, those drinking more than 2 cups a day had a 54% lower risk of age-related declines in memory, orientation, ability to follow commands and attention.

Those drinking 4 to 6 cups of green tea a week (1 cup a day) had a 38 lower risk of declines in brain function.

Green tea's primary protective agent is thought to be its catechin phytonutrient epigallocatechingallate or EGCG. Research shows this highly potent antioxidant:

helps prevent the formation of B-amyloid, a protein whose accumulation is recognized as causing Alzheimer's (Basianetto S, Eur J Neurosci Jan 2006).
protects brain cells by chelating (removing) iron, which might otherwise produce destructive free radicals (Reznichenko L, J Neurochem, March 2006).
helps prevent oxidative stress-induced brain cell death by "talking" to brain cells' genes responsible for cell cycling and survival. Specifically, EGCG tells the genes in neurons to decrease production of caspase 3, an enzyme involved in initiating programmed cell death. (Park HJ, Life Sci Jan 2006; Levites Y. J Biol Chem, 2002)
promotes memory-related learning ability by protecting cells in the hippocampus, a part of the brain involved in spatial cognition and memory-related learning ability, from free radical damage (Haque AM, J Nutr April 2006).

Green Tea Fights the Flu
A cup of green tea may help prevent or lessen the duration of the flu. In a lab study, published in the November 2005 issue of Antiviral Research, EGCG dramatically inhibited influenza virus replication in cell culture in all the subtypes of influenza virus tested. EGCG appears to suppress viral RNA synthesis by altering the properties of the viral membrane.

Pepper increases EGCG availability
An animal study suggests that consuming the spice, black pepper, when drinking green tea can significantly increase the amount of epigallocatechin-3-gallate (EGCG) absorbed. In this study, rats and mice given green tea along with piperine (a bioactive component in black pepper) absorbed 130% more EGCG than control animals receiving EGCG alone.

In this study, piperine was found to inhibit the glucuronidation of EGCG in the intestines. Glucuronidation is a chemical pathway that serves as one of the major ways our bodies convert drugs, steroids, and many other substances into metabolites that can then be excreted into the urine or bile. By inhibiting EGCG's glucuronidation, piperine allowed more of this catechin to be absorbed and utilized. So, next time you have a cup of green tea along with a meal, be sure to spice up your soup, salad and/or entrée with a little freshly ground black pepper.

Description

Green tea is the least processed and thus provides the most antioxidant polyphenols, notably a catechin called epigallocatechin-3-gallate (EGCG), which is believed to be responsible for most of the health benefits linked to green tea. Green tea is made by briefly steaming the just harvested leaves, rendering them soft and pliable and preventing them from fermenting or changing color. After steaming, the leaves are rolled, then spread out and "fired" (dried with hot air or pan-fried in a wok) until they are crisp. The resulting greenish-yellow tea has a green, slightly astringent flavor close to the taste of the fresh leaf.

Green Tea and Caffeine
Green tea contains caffeine, although half that found in coffee. The amount of caffeine that ends up in your cup of green tea will vary according to the amount of tea used, the length of time the leaves are infused, and if you drink the first or second infusion. Most of the caffeine in green tea is extracted into the water the first time the tea is infused.The table below compares the average amount of caffeine found in tea, other caffeinated drinks and chocolate.

There is limited research in the published literature comparing the caffeine content of green vs black tea. A recent study1 measured the caffeine content in the dry matter of the tea leaves, an approach that allows for control of any confounding variables related to preparation techniques that may impact the caffeine content in the final tea product. This study found that the caffeine content of one gram of black tea ranged from 22-28 milligrams while the caffeine content of one gram of green tea ranged from 11-20 milligrams, reflecting a significant difference. (Please note that not all of the caffeine from the tea leaves is extracted into the tea beverage, so these numbers only provide a relative level of caffeine difference between black and green tea, and not a reflection on the absolute amount contained in each tea beverage.)

1. Khokhar S, Magnusdottir SG. Total phenol, catechin, and caffeine contents of teas commonly consumed in the United kingdom. J Agric Food Chem. 2002 Jan 30;50(3):565-70.
2.Gray J (1998). Caffeine, coffee and health. Nutrition and Food Science 6:314-319.
3. Unpublished data
4. USDA National Nutrient Database for Standard Reference, Release 17 (2004)
5. Ministry of Agriculture, Fisheries and Food (MAFF) (1998). Survey of caffeine and other methylxanthines in energy drinks and other caffeine containing products (updated). Food Surveillance Information Sheet No. 144 (No. 103 revised). London.
Source: Tea Council Fact Sheet, http://www.teacouncil.co.uk/

What is a safe intake of caffeine?
The safety of caffeine consumption remains a topic of major debate in the research literature. To our knowledge, no studies have shown problems with caffeine consumption of less than 75 milligrams per day. Most studies showing potentially problematic effects of caffeine consumption have focused on intakes above 200 milligrams. In addition, there appears to be a significant difference in people’s sensitivity to caffeine. People sensitive to caffeine may wish to drink a decaffeinated green tea or, since approximately 80% of the caffeine is released in the first infusion, simply infuse the tea for 45 seconds in hot water, then pour off the liquid. Add more hot water and steep again. This method removes most of the tea's caffeine but little of its flavor and aroma.

At least two beneficial components in green tea—its catechins and the amino acid L-theanine—lessen the impact of its caffeine. When green tea is brewed, its caffeine combines with catechins in the water, reducing the caffeine's activity compared to coffee or cocoa. In addition, L-theanine, which is only found in tea plants and some mushrooms, directly stimulates the production of alpha brain waves, calming the body while promoting a state of relaxed awareness.

Green Tea and Drug Interactions
The tannins in green tea may decrease the absorption and thus the activity of the following drugs: atropine, Cardec DM®, codeine, ephedrine and pseudoephedrine, Lomotil®, Lonox®, theoplylline, aminophylline, and warfarin.

The caffeine in green tea may interact with the following drugs heightening their effects to dangerous levels: ephedrine and pseudoephedrine, theophylline, aminophylline.

Green Tea and Iron Absorption
Due to their high tannin-content, teas, including green tea, have been shown to prevent iron absorption. While this effect is helpful in persons with too much iron, consuming several cups of green tea daily may not be a good idea for persons deficient in iron or susceptible to iron deficiency.

Limit Green Tea Consumption During the First Trimester of Pregnancy
According to a study published in the March 2005 issue of Cancer Research, ECGC, a catechin present in green tea in amounts about 5 times higher than in black tea, inhibits the enzyme dihydrofolate reductase (DHFR), which cancer cells need to be able to grow, and which is a well recognized target of anti-cancer drugs.

Scientists decided to look at ECGC after they realized the green tea catechin looks a lot like the cancer drug methotrexate, which prevents cancer cells from making DNA by inhibiting the DHFR enzyme. They discovered that ECGC kills cancer cells in the same way as the drug.

Although ECGC binds strongly to DHFR, which is essential in both healthy and cancerous cells, it does not bind as tightly as methotrexate, so its side effects on healthy cells are less severe than those of the drug.

ECGC's binding to DHFR may also explain why women who drink large amounts of green tea around the time they conceive and early in their pregnancy may have an increased risk of having a child with spina bifida or other neural tube disorders.

Women are advised to take supplements of folic acid when trying to conceive and during the first trimester (the first 3 months) of pregnancy because it is during this time period that the baby's neural tube is developing. Folic acid helps ensure normal development and protects against spina bifida by enabling the production of the enzyme DHFR. While a cup or two of green tea is unlikely to pose a problem, drinking large amounts of green tea could decrease the activity of DHFR, increasing risk of neural tube defects.

Nutritional Profile
Introduction to Food Rating System Chart
The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents (similar to other information presented in the website, this DV is calculated for 25-50 year old healthy woman); the nutrient density rating; and, the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised.

Green tea 0.07 ounces 0.00 calories Nutrient Amount DV (%) Nutrient Density World's Healthiest Foods Rating World's Healthiest Foods Rating Rule excellent DV>=75% OR Density>=7.6 AND DV>=10% very good DV>=50% OR Density>=3.4 AND DV>=5% good DV>=25% OR Density>=1.5 AND DV>=2.5%

In Depth Nutritional Analysis

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