Good carbs are: found in the wild nature, usually carbs combined with fibers, water, vitamins and various microelements. Bad carbs: originate from good carbs by the process of refining. As a rule bad carbs are not found in nature, they are always are product of processing of the good carbs. It could be a mechanical refining – like grinding grains with resultant removal of fibers, thermal – boiling of beets and separation of long chain carbs from fibers and then split of the long chan carbs into short chai simple sugars. Even with fruits – whole fruit is healthy, but juice it, boil it and add some sugar – and you have a bad sugar as a result.