White teaWhite tea is primarily grown in China. There are studies that prove the health benefits of the white tea. You can read more about on Wikipedia.
Oolong TeaOolong tea is also grown in China. The oolong leaf contains calcium, manganese, copper, carotin, selenium, and potassium, Vitamin A, B, C, E and K. You can read more about oolong's health benefits on Organic Facts.
Yerba Mate TeaYerba mate contains potassium, magnesium, and manganese. It also contains 0.7% to 1.7% caffeine (coffee has up to 3.2% caffeine). Yerba mate is abundantly grown in Argentina, Bolivia, southern Brazil, Uruguay and Paraguay. You can read about the health benfits of Yerba mate on Wikipedia.
Dr Oz explains the benefits of the 3 teas in his show The Dr Oz Show. That segment has a video on his website DoctorOz. The video demonstrates what time and how many cups of teas should you consume each day. You don't have to drink all of the three. Just pick that suits your taste.