Aside from water, tea is the most commonly consumed beverage in the world. In the U.S., black tea is by far the most popular, but green tea (which accounted for just 14 percent of the tea consumed in America in 2015) may have particularly powerful health benefits.
Researchers believe that catechins give green tea its “super powers.” Green tea is rich in naturally occurring plant compounds called polyphenols, which can account for up to 30 percent of its dry leaf weight.
Within that group of polyphenols is epigallocatechin-3-gallate (EGCG), one of the most powerful catechins — the same polyphenol that is in black tea, and which has been shown to positively impact a number of illnesses and conditions. Like black tea, green tea also contains L-theanine, an amino acid that crosses the blood-brain barrier and has psychoactive properties.
Source: https://articles.mercola.com/sites/articles/archive/2015/04/23/green-tea-dementia.aspx
