Polyphenols found in green tea include epigallocatechin gallate (EGCG), epicatechin gallate, epicatechins and flavanols,[1] which are under laboratory research for their potential effects in vivo.[4] Other components include three kinds of flavonoids, known as kaempferol, quercetin, and myricetin.[5] Although the mean content of flavonoids and catechins in a cup of green tea is higher than that in the same volume of other food and drink items that are traditionally considered to promote health,[6] flavonoids and catechins have no proven biological effect in humans.[7][8]
It is used in castella, manjū, and monaka; as a topping for shaved ice (kakigōri); mixed with milk and sugar as a drink; and mixed with salt and used to flavour tempura in a mixture known as matcha-jio. It is also used as flavouring in many Western-style chocolates, candy, and desserts, such as cakes and pastries (including Swiss rolls and cheesecake), cookies, pudding, mousse, and green tea ice cream. Matcha frozen yogurt is sold in shops and can be made at home using Greek yogurt. The Japanese snack Pocky has a matcha-flavoured version. Matcha may also be mixed into other forms of tea. For example, it is added to genmaicha to form what is called matcha-iri genmaicha (literally, roasted brown rice and green tea with added matcha).

Caffeine: Everyone knows that caffeine is an external stimulant and raises blood pressure, and is actually toxic in nature (it may be fatal for some animals). Caffeine is also addictive and can have adverse effects on the liver and internal organs over the course of many years. That being said, it is the component of tea which makes it energizing and refreshing, which is why people are willing to risk it.

Matcha literally means "powdered tea." When you order traditional green tea, components from the leaves get infused into the hot water, then the leaves are discarded. With matcha, you’re drinking the actual leaves, which have been finely powdered and made into a solution, traditionally by mixing about a teaspoon of matcha powder with a third cup of hot water (heated to less than a boil), which is then whisked with a bamboo brush until it froths.

The many well-researched health benefits of green tea make it a great beverage to include in your diet for the prevention and treatment of cancer, heart problems, cardiovascular diseases, high cholesterol levels, rheumatoid arthritis, infection, tooth decay, and many others. Green tea contains an antioxidant called epigallocatechin-3 gallate (EGCG), which is also helpful in treating a variety of diseases.
Another benefit of green tea it’s is lower in caffeine than most other teas, so you may be able to drink the five cups a day that lowered psychological stress in a large group of Japanese people in a recent study done at Sendai’s Tohoku University Graduate School of Medicine. The researchers didn’t identify any particular component of green tea that might have been soothing, but animal studies suggest that one compound, EGCC, had both sedative and hypnotic effects that tamp down the body’s production of stress chemicals.

Tea culture of Korea was actively suppressed by the Japanese during the Japanese forced occupation period (1910‒1945), and the subsequent Korean War (1950‒1953) made it even harder for the Korean tea tradition to survive.[70] The restoration of the Korean way of tea began in the 1970s, around Dasolsa.[70] Commercial production of green tea in South Korea only began in the 1970s,.[71] By 2012 the industry was producing 20% as much tea as Taiwan and 3.5% as much as Japan.[72][73] Green tea is not as popular as coffee or other types of Korean teas in modern South Korea. The annual consumption per capita of green tea in South Korea in 2016 was 0.16 kg (0.35 lb), compared to 3.9 kg (8.6 lb) coffee.[74] Recently however, as the coffee market reached saturation point, South Korean tea production doubled during 2010‒2014,[75] as did tea imports during 2009-2015,[76] despite very high tariff rate (513.6% for green tea, compared to 40% for black tea, 8% for processed/roasted coffee, and 2% for raw coffee beans).