Discussions of food normally focus on nutrition and flavor. However, recently more attention is being paid to the role of food in bio-regulating functions. Foods that possess this regulatory function are called ” bio- regulatory functional food “. According to Dr. Inaba, who classifies food by his ” bio-regulatory functional food table “, green tea possesses the following functions : it has a bio-defensive function by preventing cancer through strengthing the immune system, it has a disease-preventing function, by preventing high blood pressure or diabetes, a disease-recovery function by inhibiting the rise of cholesterol, a physical rhythm-controlling function by stimulating the central nervous system with caffeine, and an aging-suppressing function by providing the body with antioxidants. Therefore, green tea is rich as a bio-regulatory food and has become a popular beverage among the new health conscious generation. It has been in use since its introduction to Japan centuries ago, now modern research has finally started to remove the veil concerning its many positive qualities. Green tea is truly a” miraculous medicine ” with an extraordinary power to prolong life. Dr. H. Inaba, Food Chemicals. ( No 11) 32 (1988).