Very high in Fibre and contains zero calories. Oat Fiber is virtually non-digestible and doesn’t provide any carbs or nutrients. You can use it in baking as a flour substitute … usually in a blend of other low carb flours such as coconut flour. Since it soaks up so much liquid, if you are substituting it in your own recipes, you need to make sure you also adjust your liquids upwards. If you suffer from constipation, oat fiber will definitely help.