BMR info is very helpful.
Here is a link. http://www.ecybex.com/education/cal...s/bmr_calc.html
Calculate your BMR based on Age sex and weight. then adjust for activity level. Take that amount then subtract 10-15%
if you go below 15% less than BMR you will lose weight slowly but some of that will be Lean Body Mass (muscle ) Not good.
NO diet will work if you eat more than your adjusted BMR.

I hope that helps, any questions let me know.
Jag