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Drink More Green Tea
All teas are made from the leaf of the
Camellia sinensis plant. Tea is a drink made by
steeping processed leaves, buds, or twigs of Camellia
sinensis in hot water for a few minutes. Processing can
include oxidation, heating, drying, and the addition of
other herbs, flowers, spices, and fruits.
There is archeological evidence that benefits of green tea have
been enjoyed for thousands of years. It has helped fuel the
rise of civilizations in China, Taiwan, Hong Kong, Japan,
Korea, and the Middle East. Green tea has recently become more
popular in the West, where traditionally black tea and coffee
is the fuel of choice.

Tea Bush |
Tea plants can grow into trees of 30 feet if left at peace, but
on tea plantations tea plants are pruned to about 3 feet. Tea
plants grow only in warm climates at altitudes ranging from sea
level to 7,000 feet. The best teas, grow at higher altitudes
where the leaves mature more slowly. A tea plant may take from
2 to 5 years to be ready for picking, but once productive, it
can provide tea leaves for close to a century. Only the
smallest and youngest leaves are picked for tea, the two leaves
and bud at the top of each young shoot.
Kinds of tea
Kinds of tea differ only in the amount of fermentation. Green
tea leaves are steamed, black tea is fermented, oolong is
partially fermented. Unfermented leaves contain the highest
concentration of polyphenols, chemicals that act as powerful
antioxidants. Steaming prevents the loss of polyphenols, which
is why there are so many more benefits to green tea.
Growing conditions like altitude, climate and soils vary, this
results in a multitude of distinctive teas. The way the leaves
are processed, is also important in developing the individual
characteristics of a tea.
Green Tea caffeine
Green tea caffeine is one half or a third as
much as in coffee. That means you can drink twice to
three times as much. The most caffeine is found in black
tea. Caffeine is stronger the smaller the tea leaf. A
higher caffeine content is in the tea leaves that are
fermented longer. Fresh tea leaves contain about 4%
caffeine.
If you do not want green tea caffeine, you can try
decaffeinated green tea, but it still has some caffeine. Not
all of the green tea caffeine can be taken out by the
decaffeinating process only most of it. There is debate about
how much of the benefits are lost by the decaffeinating
process. Some say the health benefits are ruined.
Green Tea health benefits
There are a wide variety of green tea health benefits. Some of
these claims have not been validated by scientific evidence but
some claims have been validated. One example is the Ohsaki
study.
the Ohsaki study. The study looked at
green tea consumption and mortality due to cardiovascular
disease, cancer, and all causes in Japan:
The Ohsaki National Health Insurance Cohort
Study, a population-based, prospective cohort
study initiated in 1994 among 40,530 Japanese adults aged
40 to 79 years without history of stroke, coronary heart
disease, or cancer at baseline. Participants were
followed up for up to 11 years (1995-2005) for all-cause
mortality and for up to 7 years (1995-2001) for
cause-specific mortality.
CONCLUSION: Green tea consumption is associated with reduced
mortality due to all causes and due to cardiovascular disease
but not with reduced mortality due to cancer.
Green Tea and weight loss
The combination of green tea's anti-oxidants (polyphenols) with
caffeine appears to have an effect that neither substance can
have on its own. Green tea's caffeine does not appear to raise
the heart rate or blood pressure the way that other forms of
caffeine do, but it does seem to raise the metabolic rate.
Polyphenols seem to work with the body to intensify fat
burning.
Green Tea and cancer
There have been several studies that suggest that green tea
helps protect against a range of cancers, including lung,
prostate and breast cancer. This has been attributed to
flavonoid phytochemicals called polyphenols. The polyphenols in
tea mainly belong to the type called catechins. The major
catechins in green tea leaves are epigallocatechin gallate
(EGCG), epicatechin gallate (ECG), epigallocatechin (EGC) and
epicatechin (EC). Of the catechins, EGCG is the most abundant
one in green tea leaves. White tea is almost as rich in
catechins as green tea but is different in composition and less
well studied. Black tea leaves have a much lower content of
these catechins. EGCG is brain permeable.
EGCG inhibits tumour cell growth by binding to a receptor on
cells.
A paper in the April, 2004 issue of Nature Structural & Molecular
Biology by researchers at Kyushu University in
Japan led by Hirofumi Tachibana, has shown that EGCG
inhibits tumour cell growth by binding to a receptor on
cells called 67 LR, a cell surface protein. Several
tumours produce abnormally high levels of 67 LR, and the
receptor is thought to be involved in the spread of
cancers through the body. The team showed that the growth
of human lung cancer cells that have the receptor slows
significantly when they are exposed to EGCG at the
concentrations equivalent to those in the body after
drinking only two or three cups of green tea. Many other
chemicals in green tea, including caffeine, did not
influence cancer cell growth. Nature Structural &
Molecular Biology 11, 380 - 381 (01 Apr 2004)
Lifelong tea drinkers have lower incidences of heart disease,
high cholesterol and some forms of cancer, they are less likely
to suffer from diabetes or be overweight. Fluoride in green tea
is great for your teeth and gums. Green tea may even have
potential to prevent diseases like Parkinson’s and
Alzheimer’s

Seed bearing fruits of Camellia
sinensis by Shizhao |
Green Tea for the Skin
Green tea has positive effects on the skin. Acne and eczema are
two specific areas it can help. Olive oil can be added to green
tea to make a treatment for eczema. Some notice a decrease in
the presence of acne by simply drinking green tea, even though
adding caffeine to your diet can case an increase in acne
breakouts.
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Ericales
Family: Theaceae
Genus: Camellia
Species: C. sinensis
Binomial name Camellia sinensis
By Harvey Robinson
Nothing in this essay is intended to diagnose, treat, cure or
prevent any disease. Green tea has not been approved by the
Food & Drug Administration for the treatment of any
disease.
If you are not a tea drinker, you can still get the nutritional
benefits in the convenience of a capsule
form.
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