I have taken so many years figuring out my intolerance and dodgy foods. Basically anything healthy will make me flare unfortunately. Fruit and veg is my biggest no no apart from potatoes and onions and small amounts of very well washed lettace and tomato sauces. I am lactose intolerant but I take lactase enzyme pills so I can eat as much as I want now. Without those it was hell trying to figure out what to eat, no fruit, veg, lactose.. and I don't eat fish (just have a weird thing with fish for some reason). Caffeine is very reactive for me too.
So my diet is actually very unhealthy, and processed but after all these years It is the Only reason I am in remission (even with meds).
I miss tenderstem broccoli, Brussels and cherries like mad, but just the thought of the obstructions they cause makes my stomach hurt thinking about eating them now.
I now don't snack, ever. I have lunch and dinner. And I drink only water. Nothing else now. I have days where I don't eat much, I'll just not fancy it (I think its psychological) and days where I feel constantly hungry. But I never eat huge meals anymore as it does make me suffer.
I have noticed I am getting abit dodgy with pork now, bacon I seem to be fine. But chops or even sausages and especially pork belly are starting to disagree now.
It is a hard way to learn, but I made diaries and started from fodmap (kicked me off) and then went to what I think is OK and every week Introduce what I thought is OK and just kept building it up until I knew what I introduced was reacting or not.