How long does it take to lose weight on an average.?

I'm 5'7'' and weigh 145 lbs. I just lost about 15 lbs from eating subway sandwiches from may to july. Since July to now I just eat 2 bowls of special K with strawberries a day. (one for breakfast and one at 4). I only walk about 30 minutes a day. I also have hypothyroid since birth and am on meds and all my fat is around my waist...love handles and stomach.How long does it take to lose weight on an average.?
2 bowls of cereal is not a healthy diet, you need to increase your calorie intake to around 1200 - 1500 calories per day. I know that losing weight is more difficult with an under active thyroid but assuming the med level is OK that should not cause too much of a problem. Make sure the walking is brisk, you should be slightly breathless and unable to talk and walk effectively. Increase the exercise you are doing, it will bump up your metabolic rate. By eating so little you are actually doing yourself more harm by lowering your metabolic rate.