Option 1: STAY AWAY FROM ANY FAT WHAT SO EVER. Do tons and tons and TONS of cardio, run, bike, jog until you get sick and then some. Stick to a 100% clean diet perhaps consisting of, Egg whites for breakfast, tuna for lunch, chicken for dinner. I know this isn't enough to satisfy you but you could live on that for 6 days I'm sure. oh and when I say chicken I mean a chicken breast you cook on the grill not some fatass Mcdonalds chicken club or chicken nuggets.
Option 2: During wrestling season in school, most of those guys don't really eat anything for a week straight. They have to lose around up to 8 pounds in a week. It is just water weight but it will work.
Limits are for people who have them