Originally Answered: Does green tea really make you lose weight?
Yes and no.
Yes: There are metabolism boosters in green tea, but there are in a lot of things. Technically speaking, coffee could make you lose weight, so could speed. That doesn't make them hugely good for you. The benefit of green tea is that it doesn't have a lot of the other things that are bad for you like these other drinks, and green tea (similar to the water-flush diet, or the grape fruit juice flush diet) is that it displaces high calorie drinks that you were taking in before.
No, there's really nothing in green tea that, by itself, will cause you to lose weight. Yes, it reduces your calorie intake by replacing/displacing other high calorie drinks, but no, if you don't control your eating and exercise, no you won't lose weight just because you bought into some health fad.
Give up pop, drink juice and water. It'll have pretty much the same effect.