The name for this problem is "pica". Most often cats are attracted to wool or blankets, but I have one who loves to chew on plastic (he doesn't have teeth anymore, so he just gums it).
Pica can be the result of medical problems (brain tumors, FIV, dietary imbalances, mental issues like compulsion, etc), so you should get your cat checked by the vet if you haven't already.
Once medical problems are ruled out, the treatments for pica are generally
Remove the material (as much as possible)
Make the material unpalatable (bitter sprays, which wouldn't work in your case)
Provide stimulation (it could be caused by boredom) with lots of interactive play
Provide safe chewing alternatives (rawhide, toys, raw chicken necks, etc)
Remove/reduce any environmental factors that could be causing stress.
I'm not aware of any problems SPECIFICALLY from pica with paper, but the general risks of pica are that the material could create a blockage in his digestive system and require surgery to fix. Also, if the paper material has staples, that could be an additional hazard.
I'll admit that some tough plastic items we just let Hunter gnaw on because we know there's no way he can do enough damage to cause any part to be swallowed, but that's a unique situation. Any time a cat is swallowing a non-food item you should be concerned and try to remedy the situation.