IF I did want to lose weight, I'd subtract 500 calories per day to lose one pound per week. (3500 calories ='s 1 pound).
Calories work if you understand what you need to maintain with moderate or low exercise (for women 12 times current weight should maintain, so 150 lb woman needs 150 X 12 = 1800 calories per day to maintain), understand how much to add during strenuous activity (not as much as 'they' say, but almost exactly what the women of TE say

), what food to eat (high quality whole foods, not diet crap), and what your ideal weight is.