Oolong (wulong or wu-long) tea is one of the healthiest teas, popularly called “fat killer” (high cholesterol, weight loss without dieting, to speed up metabolism). According to the degree of fermentation, it is between green and black teas. It has less theine (caffeine) than black tea and more than green tea.
Oolong or semi-fermented tea can be greenish or brown depending on the degree of fermentation. Its characteristics are more reminiscent of green tea than black tea. Oolong tea is also known as red tea and comes from the Camellia sinensis plant. just like most other types of tea.