Green tea is one of the most healthful beverages on the planet. It is a constant topic of medical studies around the world. It is ancient and its chemical properties make it potentially helpful in a range of conditions. This begins a multi-part article in which I examine how the ancient beverage helps battle many conditions, including cancer.
Tea drinking started in China about 5,000 years ago. Legend has it that tea was discovered by a Chinese emperor at this time when leaves from a bush nearby blew into his boiling water. Long ago, Traditional Chinese Medicine recommended tea for healthy individuals trying to prevent various diseases. During the Tang dynasty (618-907 AD), tea drinking as well as tea trade flourished in Asia.
True teas all come from the “Camellia sinensis” shrub. Once the leaves are plucked from the tree, the way they are processed determines what kinds of tea we get. Black teas are crushed and then exposed to oxygen before they are dried, whereas green teas are non-fermented. Oolong teas are “partially fermented.” All teas contain a group of chemicals known as “polyphenols” and are especially high in flavonoids. However, the types and amounts will depend on the way the teas are processed.
In green tea, the major polyphenol belongs to the family known as “catechins.” It also contains many other beneficial chemicals: caffeine; gallic acid; theophylline; theobromine; theaflavins; and theanine.
More than one million Americans are diagnosed with cancer each year. Another 500,000 die of cancer each year. In Asia, drinking green tea and eating soy are linked to a lower cancer rate and fewer deaths. What green tea really does in terms of preventing cancer is culled from mostly large population surveys — also known as epidemiological studies. In parts two, three and four of this series, I’ll examine specific cancers with respect to green tea.