Honestly I don't even know. I'll be good for a while and then out of nowhere I'll have stomach pain and diarrhea, with straight up liquid being not uncommon. I'm pretty sure I have a dairy allergy of some kind since every time I have some I break out in pimples and abscesses so I've completely cut that out. I've spent months at a time trying to isolate if it's a specific food I might not be able to eat but as soon as I think I have it narrowed down, the problems come back despite not eating the supposed problem foods. I spent like 6 months thinking I couldn't eat avocados without it feeling like battery acid is coming out my ass, only to try it again accidentally and be perfectly fine. There will be times where I drink heavy and eat shitty food and my system is fine and there are others where I'm eating good and I'm fucked. It's exhausting and I've got to be a pain in the ass for my friends when we get food since I can't eat a ton of stuff. Being quasi-vegan helped marginally but I still end up having problems about as often as before.

But when I was in Europe I ate like a trash disposal (including things that will 100% make me sick in the States) and drank like a fish and my system never once had an issue.