I am not good at explaining the details, but here is an interesting article that may help: <a href="http://www.examiner.com/low-carb-lifestyle-in-national/if-fiber-is-not-digested-then-why-do-we-count-the-calories-or-carbs-it">http://www.examiner.com/low-carb-lifestyle-in-national/if-fiber-is-not-digested-then-why-do-we-count-the-calories-or-carbs-it</a> I, too, wanted to subtract the carb calories from my diet which calculation would be: number of carbs times four; the sum subtracted from RDI...