White tea is the most rare and least processed of the four types of tea. The Camellia sinensis leaves are simply steamed and dried; they are not fermented, thus contain the least amount of caffeine (about three-fourths of the caffeine found in a cup of green tea). Unfortunately, white tea is very rare, thus very expensive as well. It has the mildest taste of the four types, and it doesn't have any of the grassy nuances that green and oolong teas have.6
The excitement surrounding white tea stems mainly from its power against colon cancer. An Oregon State University study has found that, among rats with colon cancer, consumption of white tea reduced the average number of cancerous polyps present about 57 percent, from 30 polyps to just 13.7 White tea is also believed to contain a higher amount of antioxidants, which are believed to be anticarcinogenic elements, than green tea.