I agree with Melissa. Diets do not work. Lifestyle changes do. I'd work on tracking the calories you eat every day and once you figured how much you are eating right now, you can determine if you are eating too much or too little. If you go either way you are going to gain weight. Reason for the weight gain on too little is because your body will slow the metabolism down because it doesn't know when it's going to be fed regularly with enough food to carry out the necessary functions. There is a tool on google which you can use to track your food and you can enter your height and weight and how active you are. If you are trying to lose weight, I would set it to sedentary so you know how much food you can eat that day so your body can carry out normal functions. Then I would use the exercise counter on Google's site so you can see how many calories you burn when you exercise.
Your goal? You want a 500 calorie deficit every day. This means you want to burn 500 more calories than you took in. Studies have found that the people who are most successful at losing weight are people who reduce calorie intake and increase activity. The reason for this is because it's much easier to reduce calories by 100 to 200 calories every day then 500, and it's easier to get into an exercise routine if one is burning 150 to 200 calories or more everyday than someone who is trying to burn 500 more calories than what they eat.
It's about gradual changes. Do not overwhelm yourself. If you drink soda all the time, switch to diet, and replace one soft drink with a glass of water until you are only having one diet soda a day. Just that change alone will give you an almost 500 calorie defict every day! With exercise, start with a walk around the block every day and increase the distance every 3 days until you find yourself walking a mile every day. Then once you met that goal, increase the intensity of the walk or maybe alternate, one day you walk a mile and the next day you bike 1 mile. As you get comfortable biking a mile, move it up to 3 miles.
You'll get there without feeling deprived and having to give up your occassional cookie or favorite food! Good luck!
Angie