Multifunctional health-promoting effects of oolong tea and its products

Oolong tea, partially fermented from Camellia sinensis leaves, exhibits significant antioxidative, anti-inflammatory, and anti-cancer activities as indicated in several in vitro and in vivo studies. However, studies on health promoting effects of oolong tea and its characteristic compounds are limited. The potential efficacy of bioactives derived from oolong tea and their roles as promising anticancer agents, their cardio-protective benefits during hypoxic conditions, effects in treating allergic disorders, potential prebiotic activities, improvement of blood lipid status in human beings, effectivity as oral hypoglycemic agent in the treatment of type 2 diabetes, and their potentials to reduce the risk of obesity have been discussed in this review. These promising studies mainly gained from animal studies might broaden the consumption and usage of the phenolic-enriched oolong tea and its products in food and pharmaceutical industries. However, potential health beneficial effects of oolong tea in humans should be further complemented by large-sized, randomized double-blind and placebo-controlled trials to consolidate potential therapeutic applications.