It is one of the most widely consumed beverages in the world. The first recorded drinking of tea is in China, with the earliest records of tea consumption dating back to the 10th century BC.
In India, tea is one of the most popular hot beverages. It is consumed daily in almost all homes, offered to guests, consumed in high amounts in domestic and official surroundings and is made with the addition of a lot of milk with or without spices. It is also served with biscuits which are dipped in the tea and eaten before consuming the tea. On April 21, 2012 the Deputy Chairman of Planning Commission (India), Montek Singh Ahluwalia, said that tea would be declared as national drink by April 2013.
In the Kashmir region of India, Kashmiri chai or noon chai, a pink, milky tea with pistachios and cardamom, is consumed primarily at special occasions, weddings, and during the winter months, commonly called it kahwah.
In the United States and Canada, 80% of tea is consumed cold, as iced tea. Sweet tea is a cultural symbol of the southern US, and is common in that portion of the country.
In the United Kingdom, especially England, it is consumed daily and often by a majority of people across the country, and indeed is perceived as one of Britain’s cultural beverages. In British homes, it is customary good manners for a host to offer tea to guests soon after their arrival. The British prefer black tea, served in mugs with milk and perhaps sugar.
There are mainly two principal botanical varieties of teas are used, the China plant (C. sinensis), used in Chinese, Formosan and Japanese teas and another one is the clonal Assam tea plant (C. sinensis assamica), used in most Indian and other teas (but not Darjeeling).
The chief criterion for the classification of tea plants are the size of leaves. Primary three classifications of tea leaves are Assam type, characterized by the largest leaves; China type, characterized by the smallest leaves; and Cambod type, characterized by leaves of intermediate size. The smaller the leaf, the more expensive the tea.
Teas can generally be divided into categories based on how they are processed. There are at least six different types of tea: white, yellow, green, oolong, black, and post-fermented teas of which the most commonly found on the market are black, green, oolong, and white. Some varieties, such as traditional oolong tea and Pu-erh tea, a post-fermented tea, can be used medicinally.
HEALTH BENEFITS
Green tea- There are various chemical compounds found in green tea like: polyphenols and flavonoids alkaloids, such as caffeine and theobromine, carbohydrate, stannins, minerals such as fluoride and aluminum
- EGCG (epigallocatechin gallate) is one of the very powerful antioxidants and is believed to be an important player in the therapeutic qualities of green tea
- Tea also contains catechins, a type of antioxidant.
- White and green teas are highest in catechins concentration, while black tea has substantially fewer due to its oxidative preparation.
- Catechins in green tea possess anticancer properties; it fights against “cancer in various organs, including the colorectal and liver.
- Green tea is known to exert anti-obesity, antidiabetic, and anti-inflammatory effects.
- Green tea contains “Branched-chain amino acids which may prevent progressive hepatic failure in patients with chronic liver diseases, and might be effective for the suppression of obesity-related liver carcinogenesis.”
- Green tea drinking has recently proven to be associated with cell-mediated immune function of the human body.
- Green tea plays an important role in improving beneficial intestinal microflora, as well as providing immunity against intestinal disorders and in protecting cell membranes from oxidative damage.
- Green tea also prevents dental caries due to the presence of fluorine.
- The role of green tea is well established in normalizing blood pressure, lipid depressing activity, prevention of coronary heart diseases and diabetes by reducing the blood-glucose activity.
- Green tea also possesses germicidal and germistatic activities against various gram-positive and gram negative human pathogenic bacteria.
- Both green and black tea infusions contain a number of antioxidants, mainly catechins that have anti-carcinogenic, anti-mutagenic and anti-tumoric properties.
- Green tea is famous for its calming effect on both body and mind. This calming effect is caused by the L- Theanine amino acid found in the leaves of green tea.
- Tea prevents the rise of homocysteine which is known to be an important and significant risk factor for cardiovascular diseases, due to the content of vitamin M in tea. The vitamin M, which is a B complex vitamin, assists in preventing cancer and it also plays an important part in the health of the nervous system, the eyes and other systems.
- Green tea contains caffeine and it has been used to increase alertness. Green tea has also been used to prevent/delay Parkinson’s disease.
- Green Tea also prevents baldness by stimulating the hair follicles.
- Green tea is a natural antiseptic. It cures the inflamed skin, sun burn and blackish spot around the eye. It has an anti-aging property.
- Boston University study has concluded that short and long-term black tea consumption reverses endothelial vasomotor dysfunction in patients with coronary artery disease.
- 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 mixedmicelles.
- Catechins, a group of polyphenol antioxidants found in white tea, have been found to reduce cholesterol, decrease blood pressure, and improve the function of blood vessels, thereby decreasing the risk of cardiovascular disease.
- The antioxidants found in white tea may also help bolster the immune system, particularly in immune compromised humans and animals.
- A study showed that white tea has high anti-inflammatory, antioxidant, anti-collagenase, and anti-elastase properties which could potentially reduce the risks of developing rheumatoid arthritis, some cancers, heart disease and slow the enzymatic break-down of elastin and collagen, traits which accompany aging.
- Tea contains oxalates that can lead to kidney stones; however, the bioavailability of this oxalate is not very high. The risk therefore is not very high.
- Tea leaves contain fluoride; older mature leaves contain more of the chemical that is known to cause osteofluorosis and even fractures with high intake of tea.
- Perhaps the biggest cause of tea-related side effects is the methylxanthine – caffeine. It causes a rise in blood pressure which in turn can result in a heart stroke and an increase in eye pressure worsening glaucoma.
- Caffeine is the reason why tea is considered a diuretic.
- Caffeine disturbs sleep patterns and causes insomnia.
- Two cups of tea provide around 200 mg of caffeine, more than this amount is not advisable for pregnant women as it can lead to miscarriages.
- Similarly, lactating women should avoid too much tea of their little ones will experience bowel irritability.
- Conditions linked with prolonged or excessive consumption of black tea include ovarian cancer, uterine cancer, diabetes, hypertension, irritable bowel syndrome and anemia.
- Tea should not be taken within one hour before and after meal, as it does not allow the iron of the meal to absorb in the body. This may results anemia.
It is interesting to know that adding milk to tea negates all the health effects of the beverage. This is because casein in the milk binds with the beneficial EGCG and prevents it from exercising a relaxing effect on arteries.
So tea should be drink in moderate amount otherwise you may face one or more of the above mentioned side effects.