If you're over 200 lbs and have a range of 1200-1550, you've likely set a goal that's too aggressively short, or you aren't accounting for your activity properly.
Your BMR is how much you need to eat to maintain your current weight if you did nothing at all... not get out of bed, not walk to the store, no activity at all.
How you figure out this stuff is explained here: www.sparkpeople.com/resource/calorie_calcu
If you are losing weight in your range, eat there! Adjust your goal date out farther and I bet Sparkpeople will adjust your range, too. Also make sure you're accounting for it.
I eat around 1700-1900, and have since the first (actually, I was higher... 1800-2100) and yes, I've continued to lose.
Worry about it not working when it stops working. :) If it's working for you now, stop fretting, and go with it!
You will likely not stay in the same range throughout your journey; as you get smaller, your body's needs will decrease, and consequently, so will your BMR. But the more active ou are, the more you get to eat. :) Also start strength training. That will also boost your metabolism and help you burn more calories at rest.
Edited by: DRAGONCHILDE at: 1/20/2013 (14:29)