wu-yi diet chinese tea?

Actually, Wu-Yi is the name of a mountain in Fujian Province China, which has been famous for tea since ancient time. Tea from Wu Yi Mountain can fetch over US$1000 a gram. The region produces all kind of tea including Oolong tea, Pu-erh Tea and Tie Guan Yin tea etc. But unfortunately, there is no such tea as Wu-Yi tea, I think it’s the name of the brand or falsely claims to be the non-existing “Wu-Yi” tea.
If you are looking for tea to slim down, I suggest Green tea may be your best bet, according to some Swedish and Japanese researches, Green tea can lower a person’s body fat a bit in comparison to subjects which don’t take green tea. And the anti-oxidant in Green tea is very beneficial to health. Besides, the caffeine in (any) tea will kick your metabolism up a notch and burn more calories. But the main part still relies on good diet and exercise.
As for tea or caplets? Personally I would choose tea over caplets (am a tea lover). But if you have concern about staining your teeth, caplets are better choice (2 caplets apx = 4 cups of tea). Good luck.

I don't believe that you can buy this tea in caplets at your local drug store. It is just a tea and therefore will provide nutritional benefits, but it will not make you lose weight. It may help, though. I drink Wuyi Cliff tea (Da Hong Pao), also known as "Big Red Robe", regularly.

Wu-Yi is the same as the very common oolong tea, which is just a partially-fermented tea that is halfway between green (non-fermented) and black (fully fermented) tea. Don't waste your money. If you like the tea (which I do) then enjoy it. Just don't pay a bunch for "Wu-Yi" tea and then expect it to cause you to lose weight, because it won't.