It can not be done without losing muscle and even at that it's very unhealty.

A good diet you will lose 1-1/12lbs of fat per week and preserve your muscle. If you are doing it right 10lbs off looks like you lost 20-25 anyway since you saved all the muscle and that is the point. A diet can not be rushed. You didn't gain 30lbs in a month and you won't lose it in a month.

__________________
The Fool say in his heart "There is no God"