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Benefits of Black Tea
Black tea is a type of tea that is more oxidized than oolong, green and white
teas. All four types are made from leaves of the shrub Camellia sinensis. Black tea is generally stronger in flavour than the less oxidized teas. Two principal varieties of the species are used � the small-leaved Chinese variety plant , used for most other types of teas, and the large-leaved Assamese plant , which was traditionally mainly used for black tea, although in recent years some green and white have been produced.
In Chinese languages and the languages of neighbouring countries, black tea is
known as "red tea" , a description of the colour of the liquid; the Western term
"black tea" refers to the colour of the oxidized leaves. In Chinese, "black tea"
is a commonly-used classification for post-fermented teas, such as Pu-erh tea;
outside of China and its neighbouring countries, "red tea" more commonly refers
to rooibos, a South African tisane.
While green tea usually loses its flavour within a year, black tea retains its
flavour for several years. For this reason, it has long been an article of
trade, and compressed bricks of black tea even served as a form of de facto
currency in Mongolia, Tibet and Siberia into the 19th century. Although green
tea has recently seen a revival due to its purported health benefits, black tea
still accounts for over ninety per cent of all tea sold in the West.
Black tea is often blended and mixed with various other plants in order to
obtain a beverage.
Benefits
A 2001 Boston University study concluded that short and long-term black tea
consumption reverses endothelial vasomotor dysfunction in patients with coronary
artery disease. This finding may partly explain the association between tea
intake and decreased cardiovascular disease events. In 2006, a German study
concluded that the addition of milk prevents vascular protective effects of
tea.Theaflavin-3-gallate, a theaflavin derivative found in black tea, could
reduce the incorporation of cholesterol into mixed micelles.
Cardiovascular Health
Black
tea is abundant in antioxidants, such as flavonoids, demonstrated to prevent the
oxidation of LDL cholesterol, preventing damage in both the bloodstream and at
artery walls, and lowering the risk of heart disease. Additionally, it has been
shown that black tea flavonoids are able to both improve coronary vasodilation
and reduce clots. Polypehnols found in black tea are also very strong
antioxidants, and the manganese in black tea may reduce the risk of coronary
heart disease by helping cardiac muscle function.
Cancer Prevention
Polyphenols in tea seem to help in preventing formation of potential carcinogens
in the body, particularly in certain types of cancer, such as ovarian, lung,
prostate, colorectal, and bladder. Other studies reveal that black tea may help
prevent stomach, prostate, and breast cancer. A compound in black tea called
TF-2 causes such cancer cells to go into apoptosis (programmed cell death) while
normal cells remain unaffected. One study on oral cancer showed that consuming
black tea can significantly reduce the risk of oral cancer, particularly in
those who smoke cigarettes and use other tobacco products.
Skin and Hair Health
 The antioxidants in green tea may help keep your skin from being plagued by acne, and in some cases have been demonstrated to function equally as well as the harsher benzoyl peroxide used in so many skin products.
Bone and Connective Tissue
Studies indicate that the bones of regular tea drinkers are stronger than those of non-tea drinkers, even when other variables were adjusted for. Scientists theorize it may be an effect of the powerful tea's phytochemicals.
Digestive Tract Health
The tannins in tea have a therapeutic effect on gastric and intestinal illnesses and make it a great digestive aid, used in China as such for thousands of years. These tannins decrease intestinal activity and exercise an antidiarrheal effect. The polyphenols in green tea have been demonstrated to have an effect on intestinal inflammation suffered by people afflicted with conditions like irritable bowel syndrome.
Brain and Nervous System
Unlike high levels of caffeine found in coffee, the low amounts in black tea promote blood flow in the brain without over stimulating the heart. The caffeine in black tea hones mental focus and concentration and studies show that the amino acid L-theanine found in black tea can help you relax and concentrate more fully on tasks. Black tea has been shown to reduce levels of the stress hormone cortisol after a month of drinking four cups of tea daily. The caffeine in black tea might also give your memory the boost it needs for a few hours and some studies suggest that a regular tea habit may help protect against Parkinson's disease.
Increased Energy
 In moderation caffeine can be a benefit - in black tea it stimulates the
metabolism, increases brain function and aids alertness. The caffeine in tea
acts as more of a subtle stimulant, taking more than a few minutes to take
effect, rather than hitting your system as quickly as coffee or cola. This
effect is assisted by another compound found only in tea, theophylline. While
caffeine chiefly targets the brain and muscles, theophylline stimulates the
respiratory system, heart and kidneys. This helps maintain a healthy
cardiovascular system.
Oral Health
Research suggests that catechin antioxidants in black tea may reduce oral
cancers. Tea's polyphenols and tannin perform as antibiotics, preventing
bacteria that cause tooth decay, and the polyphenols in tea can help to keep
in check the bacteria that cause bad breath.
Immune System
Tea is full of substances called "tannins," which studies have shown have the
ability to fight viruses such as influenza, dysentery and hepatitis. One such
tannin named "catechin" helps suppress tumors. Black tea also contains
alkylamine antigens, which help boost immune response.
Dated 11 January 2013
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