What Are The Different Teas From Around the World?
For centuries the major tea producing countries have been in Asia, though Africa and even the U.S., on a small scale now grow the evergreen from which tea leaves come. China, Japan and India have long been known as the source of most tea products, with Taiwan and Ceylon contributing in the last two hundred years.
From China come several of the teas that grace tables around the globe, both green and black.
The green tea of China is grown at high elevations, from 2,500-4,500 feet (762m-1372m) above sea level. Climatic conditions provide for excellent growing conditions, though the labor intensive nature of tea growing makes them difficult to care for there. There are some varieties that are ready for harvesting for only a few weeks out of the year, making them all the more difficult to process.
Dragon Well is a delicious green tea that comes from China. Its flat, shiny leaves that hint of chestnuts have been enjoyed by the Chinese for centuries. Another popular green tea from China is the Jasmine Balls variety. Rolled into a ball by tea workers, the long leaves are prepared by surrounding them with Jasmine flowers.
Keemun tea, which has been consumed in Great Britain for 150 years, also has its origins in China. As a black tea, it’s actually more popular in Europe than its home country.
Most of the green tea shipped around the planet also originates in China, Japan and Taiwan.
Japan’s production is among the highest of any country, thanks to yields of 1,500 pounds per acre of this fine plant. Much of that comes from the Shizuoka region, south of Tokyo. The country consumes 98% of the home grown product, though, so it often seems as if they are one of the minor producers.
One of the most popular green teas in Japan is a variety known as Sencha. Served throughout the country, tea lovers will find it in any restaurant or store. Gyokuro is another very common tea in Japan, one with a caffeine content that is unusually high.
Matcha green tea is a type traditionally reserved for Japanese tea ceremonies, but now finds its way into many everyday circumstances where tea is consumed.
Hojicha, a kind of roasted tea, is also popular in Japan and has the advantage of having very little caffeine. Perfect for those who love tea, but are sensitive to the stimulant.
But by all accounts, India is and remains the world’s most important tea producer. Demand, both internally and throughout the world, is so high that even this giant of tea production can’t satisfy it all.
For the first time in years there are appearing shortages of Indian teas. The supply has become so tight that India now imports tea from Kenya, Indonesia and Vietnam to blend with native grown product. Kenya is among the world’s largest exporters of black tea leaf.
India has dozens of different teas. There is the world-famous Darjeeling, of course. But there is also the Assam black, the Puttabong green and the Iyerpadi Estate black, popular for over a hundred years.
Naturally, there are many others one could mention. Rooibos from South Africa is becoming increasingly popular in the U.S. and elsewhere. The Formosa Oolong from Taiwan has been on tables around the world for decades, if not centuries. The delightful teas of Ceylon have had a following for two hundred years.
No tea drinker would want to be restricted to a single country’s output, since - like coffee - there are so many delightful blends from around the world. Internationalism is the hallmark of any tea devoted drinker. Drink up!
Can Tea Prevent Heart Disease?
There are numerous studies that lend credence to a popular idea that tea can help improve heart health but the answer is there is no conclusive evidence that tea prevents heart disease.
Tea contains a type of polyphenol compound called catechins. Many teas undergo oxidation of catechins, producing theaflavins. Which, and how much, of each type of compound varies between types of tea.
White teas undergo the least processing, typically being protected from oxidation. The buds are harvested young and they don’t go through the drying process that causes other teas to darken. That leaves all the original catechins intact. Green teas undergo slight oxidation and black teas get the most. But each type still has heart health benefits, despite the differing concentrations and forms of polyphenols.
In one six year Dutch study of almost 5,000 men and women, those who drank a little more than a cup and a half per day had a risk of heart attack only two-thirds that of non-tea drinkers. A Japanese study followed over 8,500 men and women for 12 years. It found those who drank at least four cups of green tea per day had about half the risk of coronary disease of non-tea drinkers.
Tea is known to help reduce the formation of the harmful form of cholesterol, LDL. The flavonoids in tea prevent it from oxidizing. That adds to the beneficial effects by decreasing the risk of hardening of the arteries.
It isn’t only green tea which has heart health benefits, though.
Heart attack and blood pressure are closely related. Higher blood pressure increases the risk of heart attack, as well as contributing to other health problems.
Black tea consumption helps reduce blood pressure by reducing the risk of atherosclerosis, which interferes with the ability of blood vessels to relax. Blood pressure measurements in one study were lower among tea drinkers. The risk of hypertension (high blood pressure) were cut in half by consuming just one cup per day. For those who consumed three cups per day, the risk was lowered by two-thirds.
Myocardial infarction is one common form of heart attack. A Harvard study done ten years ago found that a single cup of black tea per day lowered Myocardial infarction risk by 44%, compared to non-tea drinkers.
One study suggests that the mechanism may be, in part, the result of tea’s ability to reduce clotting. Participants in the study who drank black tea had lower levels of a blood protein associated with coagulation.
Tea drinking can help those who do suffer a heart attack increase their chances of surviving, according to more than one study. A Boston study of 1,900 people who had heart attacks related their recovery to tea consumption. The more tea they drank, the lower the death rate, 28% lower for those who had at least two cups per week.
The good news is there is no known downside to moderate daily tea consumption. It’s a smart choice.
Can Tea Help Prevent Cancer?
The short answer to the question in the title is: no. But there are many studies that give weight to the belief that it certainly helps.
Lung, prostate, breast, bladder and other cancers have all been the subject of intense research over the past 50 years. All of them have been favorably influenced by compounds commonly found in tea.
One of the most promising of recent finds is the identification of an antioxidant called EGCG (epigallocatechin gallate).
Antioxidants have long been believed to help hinder or slow the growth of cancer cells and tumors. U.S. National Cancer Institute studies have shown that catechins, a component of tea, inactivate oxidants, reducing the number and size of tumors.
EGCG may be one of the reasons.
Patients in a recent Japanese study at Kyushu University drank two to three cups of green tea per day, rich in EGCG. The researchers found that human lung cancer cells grew more slowly when they did. In test tube studies, EGCG inhibited an enzyme that cancer cells require in order to grow and divide.
A Spanish/British co-study reinforces the idea. Researchers at the University of Murcia and the John Innes Center in England found that EGCG in green tea prevented cancer cells from growing large enough to divide. The mechanism is believed to be the result of EGCG’s ability to bind to the specific enzyme (dihydrofolate reductase) needed.
USC (University of Southern California) researchers studying breast cancer found similar results. Green tea drinkers had a lower incidence of tumors, even adjusting for other factors such as family history, exercise and diet. Here, one important factor appears to be the ability of certain compounds in tea to inhibit the growth of blood vessels.
Cancer cells, just like any other, need nutrients from blood in order to grow. They stimulate the growth of blood vessels in order to supply themselves. Tea inhibits that ability, according to a joint study by the University of California and the University of Texas.
Other studies show that drinking five cups per day can help boost the immune system, providing the body with an ability to combat emerging cancer cells. Alkylamine antigens are thought to be responsible. Ingesting them by drinking tea produces a more vigorous response against tumors.
Another study examined bladder cancer. An extract made from green tea altered the actions of actin, a structural protein needed by cancer cells to function. A process called ‘remodeling’ allows cancer cells to invade nearby healthy tissue. A compound made from green tea modified the cancer cell’s ability to carry out this process.
While the specific mechanisms are still a matter of ongoing research, a cluster of studies all point to tea’s ability to assist in preventing cancers. There are no known downsides to consuming a few cups per day, either. It’s a smart choice.