Evidence pointing to a boost exists in abundance. But first, let’s clarify what matcha is to begin with — in case you were trapped under something heavy these past few years. It’s basically green tea, derived from the leaves of the Camellia sinensis plant, finely ground. Oxford’s Living Dictionary cites its origins in Japan as a combo of two terms, “from matsu ‘to rub’ + cha ‘tea’, from Chinese (Mandarin dialect) chá (see tea).” Matcha masters House of Matcha say the beverage is steeped in history. “Samurai warriors drank matcha green tea before going into battle because of its energizing properties, and Zen Buddhist monks drank it as a way to flow through meditation while remaining alert,” reads the website.
A juniper berry is not a true berry, but is a seed cone with unusually fleshy and merged scales that give it a berry-like appearance. Used as a spice in European cuisine, juniper berry has been used in traditional herbal medicine to support kidney and urinary tract function, as well as to help maintain healthy blood pressure levels that are already within the normal range. The essential oil can be stimulating to the kidneys. The warming and bitter properties support digestion and can soothe intestinal gas. Juniper berry can also be warming for the joints.

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] 

Green tea has many health benefits. “It contains many nutrients, including antioxidants and anti-cancer and brain-healthy compounds,” Smith reminds us. One thing is for sure: regardless of whether or not you’ll shed pounds with green tea, drink it anyway. “All teas contain many healthful nutrients; it’s one of the healthier choices for a beverage!” Smith says.
Today, an estimated 2.5 million tons of tea leaves are produced each year throughout the world, with 20 percent of that being green tea. Green tea didn’t become popular or widely distributed outside of Asia until about the early 1900s. China, other countries in Asia, countries in North Africa, the United States and Europe currently consume the most green tea worldwide.
Update... I made this tea cold and it was amazing! I read that another reviewer said that it had no flavor? All I can imagine is that maybe he/she is not letting the bag seep long enough? Or maybe using too much water? For my cold brew, I boil 4 cups of water and seep 6 bags for about 30 min. I then add 1 Tbsp honey and about 4-6 Tbsp fresh lemon juice. I keep that in the fridge in a glass container. When I want a drink, I fill a tall glass with ice and pour it over. As the ice melts, it dilutes the tea and is the perfect flavor! Add a sprig of fresh mint in your glass and it's even better! This is my everyday drink... delicious hot or cold!
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).