How many miles should you walk to lose weight?

It is not so much the miles you walk as the time you spend walking and the speed at which you walk. For example, start out with 10 minutes of brisk walking everyday for a week. Then add 2 minutes per day for another week.
Continue to add 2 minutes to your walking time each week until you are spending 30 to 45 minutes per day at a brisk walk. If you do not add extra calories to your diet you should begin to lose weight.