Let me guess, you saw it on Dr. Oz?
Skip it. There's no evidence it actually does anything, and there's no such thing as a natural "fat burner" - nothing you eat can burn fat. Our bodies don't work that way.
This comes up frequently, and here's a couple of the existing threads: www.sparkpeople.com/myspark/messageboard.a
Dr. Oz is not a reliable source of any kind of advice. He was a very competent heart surgeon, but since his meteoric rise on Oprah's coattails he's become little more than a corporate shill who's known for hawking useless products with little research to back them up. I have actually heard him say "Because it's natural, it's safe."
Avoid his advice.