Researchers from the Netherlands confirmed in a recent study that two green tea compounds, L-theanine and caffeine, can significantly boost levels of attention and alertness, building on what is already known about the brain benefits of green tea. The drink is less likely to make you jittery and anxious than other energy-boosting drinks, because it contains lower levels of caffeine than other teas or coffee. In another study published in the American Journal of Clinical Nutrition, researchers discovered that drinking just one cup of green tea a day made people age 55 and older 38 percent less likely to experience a decline in their mental abilities. Drinking a second cup daily made them 54 percent less likely to show mental declines.
Grown under shade for three weeks prior to plucking, gyokuro is one of the most exclusive varieties of tea produced in Japan. 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.