OK, normally I would not consider my own, or anyone’s, personal gastro-intestinal

OK, normally I would not consider my own, or anyone’s, personal gastro-intestinal reactions to restaurants to be worth noting. And certainly it’s unfair to the establishment since, hey, we’re all different. But I can’t help wondering about this. Years ago, I went through a period of having lunch at the Grand Central Bakery Cafe in Pioneer Square. Eventually I realized, no, there was just no mistaking it, the place was giving me a stomach ache every single time. So I stopped going. Many years passed, I left town, came back, the place was completely remodeled, its lunch menu completely changed. And so I decided to join one of my delightful co-workers there for lunch yesterday. Nothing fancy. A sandwich, soup. And got the IDENTICAL stomach ache. Is this possible? Anyone have any insights for me?