How to lose 7 kg in a week!

Someone just showed me an advertisement in a yesterday's newspaper. A kind of herbs that can help you burn your fat and reduce your weight to 7 - 8 kgs in a week! Wooowwww...too good to be true...
For a girl with 60 kg and 165 cm height I think I'm in a fat girl category...
So, Starting tomorrow, I will challenge myself, taking that recommended herbs for a week in very tight schedule, hoping that i will lose 7 kg in only a week. If I succeed, i will tell you what the herb's called. Wish me luck! i'll get to you all for the result next week.