Fat Grams

Wyoruby

All right everyone I've been told by my doctor that I should stay around 54 g of fat a day(perferably all from healthy sources). So I know that I'm always going to go over my fat grams that mfp sets up for me. But my question is that when i work out my HRM says the amount of fat grams I've burned, so can I add that number to my 54 g or just stick with the 54g? I know my body needs fat to work right and I don't want to deprive it and in the long run either gain the weight back or mess up my metabolisim by not getting in the right amount of nutrients.