Great question! The key to IBS, at least in my case, is the microbiome, as I explained in the article. I love onions, which didn't affect me before; maybe beans do. But now that I consume lamb's lettuce almost daily, my life has changed 1000%. FODMAPs could be involved in the worsening of IBS. Still, after the intestinal flora is restored and there is a balance of the microbiota, the danger is gaining weight because, in general, those of us who suffer from it are gourmet sybarites.