It won't taste good, but it should pass through in reasonable quantities. And if we go the genetic route, maybe remove some allergen proteins or something.

I mentioned reasonable quantities. While fiber, for instance, can help things move better and be less blocked, too much fiber will have the opposite effect. I know that too many sunflower seeds or too much flaxseed can clog you to the point where things travel backward. A small amount of flaxseed is okay, but remember that it comes from the plant used to make linen fibers. No sane person will sit and eat a washrag.

And casein, as I mentioned, is another case where moderation is needed. Sitting and eating an entire pound or two of cheese in one sitting is not a good idea at all.

Maybe even flour could be used to make things like disposable cookware. Like have a cup made out of pasta and when it starts to become unstable, use it as an ingredient in that night's meal. Or, break it up and use it for a personal meal. (More sanitary option.) Drink out of the cup and then prepare it like pasta.