"You may be able to lose a lot of weight up front. Eventually tapering off to still a very fast 1-1.5 lbs / week. Then your number of pounds lost per/week will drop as you reach your ideal weight. Each pound lost is 3500 calories under consumed for a week. However you need to stay above your resting metabolic rate (Rate if you stayed in bed basically). And you need to stay below your resting metabolic rate + Daily activity calories + Workout. (Over consuming calories will make a person gain weight of course.)"
Why do we need to stay above RMR? What happens if we eat below RMR? Why can't fat stores be used to make up the difference?