May help protect against diabetes

Tea has been proven to help protect against diabetes and diabetic complications in general, presumably through reducing insulin resistance and inflammation, among other mechanisms. As a result, both a 2021 research and a 2019 review reveal associations between frequent tea use, improved blood sugar management, and a decreased risk of acquiring type 2 diabetes. However, the precise benefits of oolong tea have not been studied as thoroughly as those of green or black tea.

Having said that, one smaller, older study suggests that oolong tea may be useful in decreasing plasma glucose in type 2 diabetic patients. However, not every research agrees on oolong tea's capacity to help prevent or alleviate type 2 diabetes symptoms, with a 2011 study involving roughly 5,000 Japanese men indicating that tea drinking may be a predictor of disease development.