Oolong tea, also known as green tea and semi-fermented tea, is a distinctive category among Chinese tea varieties with unique characteristics. Oolong tea is a high-quality tea produced through processes such as fixation, withering, shaking, semi-fermentation, and baking. It evolved from the tribute teas Dragon Ball and Phoenix Cake of the Song Dynasty and was created around 1725 (during the Qing Dynasty's Yongzheng era). After tasting, it leaves a lingering fragrance in the mouth with a sweet and fresh aftertaste. The pharmacological effects of oolong tea are particularly notable in fat decomposition and weight loss fitness. In Japan, it is called "Beauty Tea" or "Fitness Tea." Oolong tea is a unique Chinese tea category, mainly produced in northern Fujian, southern Fujian, Guangdong, and Taiwan. In recent years, small quantities have also been produced in Sichuan and Hunan provinces. Besides domestic sales in Guangdong and Fujian provinces, oolong tea is mainly exported to Japan, Southeast Asia, and Hong Kong-Macau regions.

Green tea and oolong tea are produced from the same tea plant. The biggest difference lies in whether they undergo the fermentation process. Because the catechins in tea leaves combine with each other as the fermentation temperature rises, causing the tea's color to darken, but thereby reducing the tea's astringency. The components formed by the combination of these catechins are the polyphenols in oolong tea. Both polyphenols and catechins with antioxidant effects can influence the activation of various enzymes in our bodies. Approximately half of the catechins contained in tea leaves are converted into oolong tea polyphenols. Therefore, under the dual effects of the antioxidant action of catechins and oolong tea polyphenols, oolong tea exhibits various benefits that green tea does not have.

Although the West has always been skeptical about "tea's weight loss effects," Chinese medical researchers have recently stated that oolong tea indeed has wonderful effects such as decomposing fat and promoting weight loss fitness, effectively reducing subcutaneous fat.