I have noticed that there is wide variability in the calculators available for weight loss. As a very short and small framed person I often run into calculators that absolutely refuse to let me have less than 1200 a day. Some of the calculators then would miscalculate how much I would lose on that 1200 a day. (Even WebMD miscalculates and shows me losing the same amount of weight no matter how much I exercise). However, I can go safely lower than 1200 a day and actually try to keep my calories ranging from 900 to 1200 a day. I mix it up a bit, hoping to "fool" my metabolism out of any risk of starvation mode. I have been losing weight at roughly a pound a week for a while now and still have enough energy to exercise, though my exercise is far from strenuous. My diet is lower carb and higher fat than traditional recommendations (which are still a matter of dispute). No bread. No rice. No pasta. No ice cream or other sweet treats except for fruit with a touch of sugar. I eat plenty of fruit and veggies. And a fair amount of meat. Including. Gasp! Bacon. My lipid levels are fine even with a fattier diet than I used to eat. In fact, they are improved due to weight loss.