I'm allergic to natural litters :/. Well, there is one kind at Tractor Supply that's made with corncobs that doesn't bother me, but all grass-related (including litters made with other parts of the corn plant; I guess the cobs are pretty inert as far as allergens go), grain-related, and wood-related litters make me wheeze. I haven't tried the walnut shell litter yet because it's too expensive and I've never found a farm-store equivalent, but it would probably be fine. The corncob kind is OK when it comes to odor control and other factors, but my cats aren't thrilled with pellet litters. Right now I'm using Fresh Results crystal litter, only because it's cheap on Amazon right now . If the price goes up I may go back to the corncob pellets, idk yet.