Over a thousand years ago, matcha came to Japan as an aid to meditation practice. During long hours of sitting, monks would drink matcha to remain alert yet calm. Modern science has recently confirmed the lessons of centuries of tradition. Matcha is rich in L-Theanine, a rare amino acid that actually promotes a state of relaxation and well-being by acting upon the brains functioning. While stress can induce beta waves an excited, more agitated state, L-Theanine creates alpha waves, which lead to a state of relaxed alertness. And while L-Theanine is common in all tea, matcha may contain up to five times more of this amino acid than common black and green teas.
One-1/2 teaspoon serving of matcha, no more than once daily, is certainly a valuable addition to any diet, says Zeitlin. Like with another substance currently having a moment, turmeric, you can get your dose by eating or drinking it, though Zeitlin says drinking it as a tea, how it was initially intended, provides all the benefits without the added calories.
In 2013, global production of green tea was approximately 1.7 million tonnes, with a forecast to double in volume by 2023.[30] As of 2015, China provided 80% of the world's green tea market, leading to its green tea exports rising by 9% annually, while exporting 325,000 tonnes in 2015.[31] In 2015, the US was the largest importer of Chinese green tea (6,800 tonnes), an increase of 10% over 2014, and Britain imported 1,900 tonnes, 15% more than in 2014.[31] In 2015, Kenya was the largest exporter of black tea in the world (443,000 tonnes).[31]
Several varieties of green tea exist, which differ substantially based on the variety of C. sinensis used, growing conditions, horticultural methods, production processing, and time of harvest. Although there has been considerable research on the possible health effects of consuming green tea regularly, there is little evidence that drinking green tea has any effects on health.[2] 

Matcha typically has more caffeine content than green tea, similar caffeine to black tea, and less caffeine than brewed coffee. Because matcha is produced from shade-grown tea bushes, the tea leaves tend to retain more of their caffeine content. In addition, since you’re consuming the ground tea leaf when sipping matcha, you’re ingesting more caffeine content than you would from the extraction of steeped green or black tea leaves. Like all drinks cultivated from caffeinated plants, however, a specific level of caffeine per cup of matcha tea will depend on the how the matcha was processed and prepared. Be sure and read the packaging carefully or ask your tea supplier directly for the caffeine information specific to the matcha you are buying.
Detox teas are great for flushing out toxins from your body. Toxins like harmful chemicals and free oxygen radicals lead to increased stress levels in the body. Stress slows down metabolism, weakens immunity, and increases the level of inflammation. And you start to gain weight, find it difficult to lose weight, suffer from constipation, gastritis, liver problems, and disturbed sleep, and feel tired all the time. The antioxidants and other phytonutrients in detox teas deactivate the harmful effects of toxins, cleanse the digestive tract, and relax your brain – promoting weight loss and better health. So, let’s get to know the top 10 detox teas that you can buy and start shedding the extra flab. Scroll down.
And not all the science has been favorable to tea. A report in the March 1 edition of The New England Journal of Medicine looking at green tea consumption in humans, found no effect on stomach cancers once adjustments were made for other factors that could affect risk. Those other factors included sex, age, history of stomach ulcer, use of tobacco or alcohol, and other dietary habits.

In a decade-long study of Japanese adults, death from all causes together, and also death from specifically heart disease and stroke, were all reduced in both women and men who drank the most green tea (5 or more cups per day) versus those who drank less than one cup per day. Another study found that those who drank the most green tea were 76% less likely to die during the 6 year study period.

Tea seeds were first brought to Japan in the early 9th century by the Buddhist monks Saicho and Kukai. During the Heian period (794–1185), Emperor Saga introduced the practice of drinking tea to the imperial family. The Zen Buddhist priest Eisai (1141–1215), founder of the Rinzai school of Buddhism, brought tea seeds from China to plant in various places in Japan. Eisai advocated that all people, not just Buddhist monks and the elite, drink tea for its health benefits.[50]

Grown under shade for three weeks prior to plucking, gyokuro is one of the most exclusive varieties of tea produced in Japan.[60] The shading technique imparts a sweeter flavor, and produces a particularly rich color thanks to the higher amounts of chlorophyll in the shaded leaf. Gyokuro tea is associated with the Uji region, the first tea-growing region in Japan. It is often made using smaller-leaf cultivars of the tea plant.[61]