The Wonder of Green Tea

TEA drinking has been a defining tradition in many civilizations ranging from China to the United Kingdom. An old Chinese proverb tells us "Drinking tea each day will starve the doctor", proving that even the ancient oriental civilization knew and acknowledged the benefits of this herb. The trend towards green tea extracts and other natural products as ingredients has been driven by the escalating consciousness to ensure overall good health by using "food as medicine". This trend has given rise to the sector of nutraceuticals, which is one of the most promising sectors in the food industry. Such a demand has augured well for the natural extracts sector. Natural extracts from fruits, vegetables and herbs contain active pharmaceutical ingredients. Examples of these are red berries, citrus fruits and grapes. Consequently, these extracts serve both to provide nutrition and also have additional functionalities, including antimicrobial and antioxidant properties. The consumption of tea can be traced as far back as 5,000 years to the reign of the Chinese emperor, Shen-Nung. Tea traveled to Europe with Jasper de Cruz, a Portuguese Jesuit priest working as a missionary in China in 1560. Portugal then established a trade route to China some four years later, which was followed immediately by other European nations. The British-operated East India Company helped to make tea the national drink of England and it remains so until this day. The profile of tea however has changed with the passing years. The main types of tea consumed today are green, black, white and oolong. Such variation rises from the methods of processing the leaves, though all originate from the same source. For instance, green teas are picked and steamed, which stops any enzymic reactions occurring as part of the oxidative process. This steaming process effectively also blocks fermentation and the associated leaf browning, which results in a final product that is green to yellow in color. Green Tea Extracts Green tea extracts are mainly sourced from China and India and are derived from the tea plant, Camellia sinensis. The primary constituents of interest are the polyphenols, particularly the catechin, epigallocatechin gallate (EGCG), and the extracts are also rich in volatile oils, vitamins, minerals and caffeine. Green tea differs from its better-known counterpart black tea in its content of EGCG, and these polyphenols are believed to be responsible for most of green tea's roles in health promotion. The main application sectors for green tea are those of beverages, functional foods, cosmetics and supplements. Since 1998, green tea extract consumption has increased steadily, with the growing number of scientific studies confirming the health benefits of these extracts. These health benefits in combating diseases may be associated with bioflavonoids, which are said to inhibit enzyme activity, especially in tumor-causing or cancerous cells. In 2007, green tea extracts accounted for one of the most promising functional ingredients. The Asian Paradox In June 2006, the University of Yale coined the term "Asian Paradox", to correspond to a phenomenon observed among the majority of the Asian population. The Asian paradox refers to the lower incidence of cardiovascular disease and cancer in Asia, despite the high incidence of heavy smokers in the region. This may be explained by the high consumption of tea, and particularly green tea, among Asians as part of their daily diet. Such a scenario is attributed to the characteristic health benefits of green tea extracts, including the antioxidant defensive property of the polyphenol EGCG. EGCG may prevent LDL oxidation, which has been shown to play a key role in the patho-physiology of arteriosclerosis. The polyphenol also has been found to reduce the amount of platelet aggregation, regulates lipids, and promotes proliferation and migration of smooth muscle cells, which are all factors iadidas