How long do you wait before re-introducing?

That's a tough question as everyone is so different... I used to only eat more "dangerous" foods when I had been feeling well for at least a week or two. Now I try my best to eat as normally as I can even when I'm not feeling too well and just remove onions, garlic, sauces etc. when don't feel like having them. In the end, what works best for me personally is listening to my body. If I feel like eating something, I usually am okay with digesting it (unless it's a craving for chocolate, that's a whole other story). If a certain food doesn't sound good right now, I avoid having it. I know that this might not work for everyone though and not a foolproof strategy for me, either. I'd love to know what others think. Karina (team member)

Yes, I usually introduce a food I used to be able to eat, during a period when I am a lot better and steadier. I will start off with a really small amount and see how I am the next day. If I'm fine, I will probably wait another day or two before trying just a little bit more of that food, and waiting a day or two to see how that goes.
I have IBS D and carrots always acted as a bit of a natural laxative for me in the past if ever I got slightly constipated (pre-IBS) So when I was tryng to re introduce carrots, I started off with one inch of a carrot! Cooked with my veg. It was fine. Next time I had 2 inches, and so on.
But even though I can eat them again now, (and I avoided them for nearly 2 years!) I find I have a limit, or I will get the slight laxative effect again. So there is a limit to the amount I can eat. I can now eat half of a medium-large-ish carrot but no more.
So, you might find there are thresholds with reintroduced foods. It is just trial and error and finding the happy spot with those foods sometimes.
And of course, some are just fine in proper portion sizes, and some just don't work at all. It's a work in progress.

It's really hard on me currently because it seems as if anything that has a slightly higher dosage of fruit sugar is off-limits for me. I used to tolerate blueberries/raspberries in a small amount 2 months ago and now I can't eat neither (and get mucus on top) ... - no berries, no pomgranate seeds, nothing :-/ It's really infuriating.

Yes it can be infuriating. I don't think I am fructose intolerant because I can easily handle honey. But I am sensitive when it comes to fruits. I used to be able to eat half a banana, or a portion of blueberries, grapes etc. That went on OK for some time so long as I didn't overdo those foods they were fine. But recently I get reactions the next day (looser bowel movements) if I eat any fruit at all. I am not sure why. I don't know if it's the fructose or the fibre! However it seems I am fine with ordinary sugar.
I haven't tried pomegranates for ages. But I never ate the seeds. They were too woody so I always spat them out. I might try pomegranate again as it doesn't maybe have too much fibre? Fibre doesn't always agree with me.