It would really help us to be able to give you a better answer if you could tell us more about what it is you need to know.
For example, are you supposed to be writing an argument about it? If so, you could talk about whether you think it is a good way to help someone lose weight of if you think it is too dangerous or just not the right way to go about things.
Or maybe you would want to talk about how it is done and what the dangers and potential benefits are (in case you are supposed to be just writing a factual paper).
In any case, feel free to let us know if you can give us more information.