Will you lose weight on 200 calories per day?

There are 3500 calories in a pound of fat. Therefore if you had a net deficit of 200 calories a day (i.e. Food calories eaten - Calories used by body functions and excercise) you would lose a pound in weight every 17.5 days (on average).

This may sound a little slow but by excercising you would build up muscle, which would provide a snowball effect to the number of calories naturally used by your body every day (more lean muscle mass = faster metabolism). So don't be discouraged and keep at it. Slower is better - you don't want to put your body into shock by cutting down too much.