What do they really do to you?

[liltyson19]

I have heard so many different things for different people about the effects positive and negative that "fat burners" have on your metabolism and other bodily finctions. Can anyone clear the air for me. I have heard that they permanently slow down your natural metabolism and then I have heard that they don't do that but that they can really harm your heart. what is the truth about these "thermogenic fat burners?" What are the effectd of taking them on your body...I am most concerned with the metabolism thing.