Corn litter?

My cat has been recently “diagnosed” with IBD after an ultrasound and 3 tests were inconclusive for lymphoma. So we’re treating for IBD with prednisolone and working on diet changes.

I’ve been using World’s Best litter which is corn based. Could that be a trigger for food allergies? They get it all over their coats, feet, and groom their fur. Curious is anyone has had an issue with food based litter.