One year ago as of 3-21 I weighed 250 lbs on a 5'2" frame. Today I weigh 162 lbs and am still losing. I used much of what has already been mentioned to lose weight. There has been some excellent info written so far on this thread. First, I have kept up with what my calorie needs are by knowing what my BMR is(Harris-Benedict is a good formula to use) and my activity level are from day to day. On the days I am not as active, I do not eat as much. I use the polar S 210 HR monitor to calculate my calories burned when a ride. This is a very accurate HR monitor when compared to some of the various internet calorie calculators and formulas for calculating calories burned. I bought myself a digital scale from Wal Mart along with several measuring cups and weigh all my food so I know exactly how many calories I'm eating. If you do not do this it is very easy to trick yourself into thinking you are eating less than you actually are. I have a spiral note book that I record what I have consumed during the day with a running tab of the total calories. I try to have between a 500 to 1000 cal deficit/day. It is not recommended you go over a 1000 cal deficit/day or you risk losing muscle. When I first started, I could only ride around 6 to 10 miles. Now, I typically ride 40 to 50 miles(2+ hrs) on my road bike and also ride my mtb at times. The main thing to consider is food is energy. Calories are a measure of the energy food provides. If you eat to many calories you will gain weight. You have to have a calorie deficit. To do this you have to know your caloric needs(BMR), daily calories burned cycling and other activities, and how many calories you are consuming and ensure a calorie deficit each day.