I've been counting calories, and researching nutrition for about a year now. i started counting calories, and cutting back to 1200 a day. it will work for a while, but after some time, your body will want more food. There's something called "Basal Metabolic Rate", and it's the amount of calories your body physically needs to maintain its main functions. It's recommended by many professionals, to never go below the BMR rate. my BMR rate is 1690. and i'm 5'8" tall. for you, it could be a lot less.
what i do, is eat 1600 every day. no matter how much, or how little i workout. if i burn more calories working out, my body can still function off 1600 and not go into "starvation" mode.