You might be superstitious about foods. “Paranoid” is a pretty strong word. Here’s some stuff to think about:
1) Food has an effect on gut function. Coloned people who eat spicy food may get a burning feeling on the toilet. Coloned people who eat broccoli and cauliflower get gas. They may have specific food intolerances, and may get heartburn or a bellyache based on their food choices. This all applies to J-pouchers, too.
2) Blockages are generally caused by a narrowing of the intestine. Food gets stuck behind the narrowing and stretches the intestine. It hurts like hell. If the narrowing makes the opening very small, or trapped food has dammed the opening, even liquid can’t get through.
3) Narrowings can be intermittent or permanent. A stricture might never open up, but a kink or twist around an adhesion will usually completely resolve when the gut moves back to a relaxed position, unless it’s very badly positioned. Permanent narrowings may likely require permanent dietary caution. Intermittent narrowings are trickier to navigate, and most likely to lead to food superstitions. The food that causes trouble when the gut is twisted or kinked becomes scary, even when the gut is fine and the food would do no harm. This is mostly a simple mechanical issue, and thorough chewing of any food makes the pieces small enough to pass about the same as any other food.
4) Gas can be a bigger problem for J-pouchers than coloned people, since most of us don’t fully trust farts, and lots of us simply won’t expel gas unless we’re on the toilet. So avoiding gas is especially helpful for J-pouchers. There’s lots of advice about this (carbonated liquids, swallowing air, etc.), but the broccoli/cauliflower/cruciferous vegetable problem is the easiest of all. Taking Beano with the first bite of those foods substantially reduces the resulting gas. Beano only works on those specific foods, though.