Green tea is particularly rich in health-promoting flavonoids (which account for 30% of the dry weight of a leaf), including catechins and their derivatives. The most abundant catechin in green tea is epigallocatechin-3-gallate (EGCG), which is thought to play a pivotal role in the green tea’s anticancer and antioxidant effects. Catechins should be considered right alongside of the better-known antioxidants like vitamins E and C as potent free radical scavengers and health-supportive for this reason.

Most of the research showing the health benefits of green tea is based on the amount of green tea typically consumed in Asian countries-about 3 cups per day (which would provide 240-320 mg of polyphenols). Just one cup of green tea supplies 20-35 mg of EGCG, which has the highest antioxidant activity of all the green tea catechins.

The health benefits of green tea have been extensively researched and, as the scientific community’s awareness of its potential benefits has increased, so have the number of new studies. As of November 2004, the PubMed database contained more than 1,000 studies on green tea, with more than 400 published in 2004! Following is a brief summary of some of the high points of this most current research.

Green tea drinkers appear to have lower risk for a wide range of diseases, from simple bacterial or viral infections to chronic degenerative conditions including cardiovascular disease, cancer, stroke, periodontal disease, and osteoporosis.

All true teas-as distinct from herbal and flower infusions, which afficiandos call tisanes-are made from the leaves of a magnolia-related evergreen tree with the botanical name of Camellia sinensis. Although reaching a height of 30 feet in the wild, on tea plantations (called gardens or estates), the plant is kept as a shrub, constantly pruned to a height of about 3 feet to encourage new growth and for convenient picking.

Tea plants grow only in warm climates but can flourish at altitudes ranging from sea level to 7,000 feet. The best teas, however, are produced by plants grown at higher altitudes where the leaves mature more slowly and yield a richer flavor. Depending upon the altitude, a new tea plant may take from 2 ½ to 5 years to be ready for commercial picking, but once productive, it can provide tea leaves for close to a century.

Tea plants produce abundant foliage, a camellia-like flower, and a berry, but only the smallest and youngest leaves are picked for tea-the two leaves and bud at the top of each young shoot. The growth of new shoots, called a flush, can occur every week at lower altitudes but takes several weeks at higher ones. The new leaves are picked by hand by “tea pluckers,” the best of whom can harvest 40 pounds per day, enough to make 10 pounds of tea.

All tea plants belong to the same species-Camellia sinensis-, but local growing conditions (altitude, climate, soils, etc.) vary, resulting in a multitude of distinctive leaves. The way the leaves are processed, however, is even more important in developing the individual characteristics of the three predominant types of tea: green, black and oolong.

Green tea is the least processed and thus provides the most antioxidant polyphenols, notably a catechin called epigallocatechin-3-gallate (EGCG), which is believed to be responsible for most of the health benefits linked to green tea. Green tea is made by briefly steaming the just harvested leaves, rendering them soft and pliable and preventing them from fermenting or changing color. After steaming, the leaves are rolled, then spread out and “fired” (dried with hot air or pan-fried in a wok) until they are crisp. The resulting greenish-yellow tea has a green, slightly astringent flavor close to the taste of the fresh leaf.

In black tea production, the leaves are first spread on withering racks and air-blown, which removes about one-third of their moisture and renders them soft and pliable. Next, they are rolled to break their cell walls, releasing the juices essential to fermentation. Once again, they are spread out and kept under high humidity to promote fermentation, which turns the leaves a dark coppery color and develops black tea’s authoritative flavor. Finally, the leaves are “fired,” producing a brownish black tea whose immersion in hot water gives a reddish-brown brew with a stronger flavor than green or oolong teas.

Oolong tea, which is made from leaves that are partially fermented before being fired, falls midway between green and black teas. Oolong is a greenish-brown tea whose flavor, color and aroma are richer than that of green tea, but more delicate than that of black.

Green tea has always been, and remains today, the most popular type of tea from China where most historians and botanists believe the tea plant originated throughout all of Asia. Why is this so? Perhaps because green tea not only captures the taste, aroma and color of spring, but delivers this delightful bouquet along with the highest concentration of beneficial phytonutrients and the least caffeine of all the teas.