Camellia sinesis, more commonly known as tea, ranks only behind water as the most popular beverage worldwide. A little more than three-fourths of tea produced is black (77%), the remaining being green tea (21%) and oolong tea (2%). The processing of tea leaves impacts the level of bioactive flavonoids.
has the least flavonoids because it oxidized enzymatically during processing. In contrast green tea is heated and dried to avoid enzymatic oxidation and oolong tea
is semifermented which reduces the level of oxidation. Thus, although representing only a small fraction of total tea produced, the oolong variety contains a broad spectrum of polyphenols and catechins. In terms of total catechins, oolong tea is on par with green tea and actually outperforms other teas in terms of total caffeine and phenolic compounds and anti-mutagenic activity. According to Chinese researchers, consuming oolong tea may have favorable effects for dieters. They studied 102 overweight men and women who consumed 8 g of oolong tea per day for 6 weeks. Almost three-fourths of the subjects lost more than 2 pounds, and one-fourth of subjects lost more than 6 pounds in just 6 weeks. There were significant reductions in waist size and subcutaneous fat from the abdominal region. Subjects also showed significant decreased in total cholesterol and triglyceride levels in the blood. These results suggest regular oolong tea may offer some assistance in facilitating weight loss and improving the blood lipid profile.
He RR, Chen L, Lin BH, Matsui Y, Yao XS, Kurihara H. Beneficial effects of oolong tea consumption on diet-induced overweight and obese subjects. Chin J Integr Med. 2009 Mar;15(1):34-41. Epub 2009 Mar 7.