What makes Fiberfit unique is its concentrated sweetness with fiber, but without calories. It is approximately 8 times sweeter than sugar.
Certain "no calorie" sweeteners achieve a 1 to 1 ratio to the sweetness of sugar by adding maltodextrin and dextrose, and in some cases, other sweeteners such as aspartame, acesulfame k, and sugar alcohols..
The US FDA allows such products to be declared as having no calories because the amount of carbohyrdrates from ingredients like maltodextrin and dexrose per single serving is under 1 gram. So they may declare the products as having 0 calories.
In applications such as cooking and baking, much large amounts of sweeteners are used. 0 calories instantly become lots of calories.