Woah.. You want to starve yourself there? 1000 calories is way too low. Look up your BMR, and times it by how active you are. Subtract 500 calories from that final number and that is how many calories you should eat a day. I do not suggest going below 1200 and even that is asking for trouble.
According to my BMR I burn 1531.7 calories. Fits perfectly into what I'm doing.