What’s with the Warning?

I got an email from visitor Sonya asking about a warning she received on the BMR Calculator.  While I answered her via email, I thought it was a good idea to put it in a post here as well.
Here’s the warning message:
WARNING: Your goal calorie level is below your current BMR. Consider revising your goal weight to an intermediate weight. That way you are never eating below your BMR. When you reach that intermediate goal weight, readjust your calories and head for your ultimate goal.
The reason that the calculator will show you that warning is that if you ate the recommended calories at the goal weight you entered, you would be eating below your basal metabolic rate (BMR).  When you eat at ultra low calorie levels you risk losing muscle mass, especially if you do so for a long period of time.  If you lose muscle mass, the act of losing the fat, which is what your goal should be, is sabotaged.  Your muscle is your metabolism, so we want to protect it and increase if at all possible.
If you get the warning, I suggest you lower your goal weight and until you don’t get the warning.  Alternatively you could put your current weight into both the current and goal weight fields on the calculator and then just subtract whatever percentage you would like, 5%, 10% 15% or up to 20%.
If you have a question about the calculators or about weight loss in general, please use the Contact page.