Oolong tea has a full bodied, but mild taste as the result of a unique partial fermentation ending with both off-green and black leaves. The tea has become more popular in the West, marketed mainly as a diet aid, but this is a narrow view of oolong. Like all teas brewed from Camellia sinensis, oolong is rich in antioxidants that can help prevent cancer, heart disease and contribute to well-being.