So why is this a good thing to know? Because today lower carb diets seem to be the way to go for those looking to lose the pounds and fast, and by knowing how to calculate net carbs you'll save yourself a lot of trouble and actually be able to eat more then someone else who was counting carbs but didn't know how to calculate net carbs. Another example of this is lets say 2 people were only allowed to have 40g of carbs per day while dieting. The first person knows how to calculate net carbs eats a total of 70g of carbs, but all from sources with a lot of fiber which added up to 30g of fiber... leaving them at 40g of net carbs taken in for the day! Now lets say the second person didn't know about net carbs and just eats 40g of carbs, but in actuality they ate 20g of net carbs then they technically could be allowed to have more!
Whether you have some extreme weight to lose, or you're simply trying to tone up while retaining muscle mass, keeping net carbs in mind can help you out a lot when choosing the right foods!