I don't get this joke. I eat Taco Bell occasionally and it's fine on my gut. I don't order the meat, though. Usually I'm getting a black bean crunch wrap with guac instead of nacho cheese.

I'm with you but it's a common enough sentiment that there's probably something to it, and I recall friends having issues over the years. For these people at best it's painful gas and at worst is [worse], so there is a large group of people who can't digest a particular common Taco Bell ingredient well.

I've seen speculation about undiagnosed lactose intolerance but frankly Taco Bell doesn't use that much cheese on their cheesiest items compared to say, a pizza, which is another very common food in the US and has way more cheese.

I wonder if it's undiagnosed gallbladder issues too.

I haven't had taco bell in a couple of decades, but I used to have issues with the beef shortly after eating there (so probably not bacteria) but no issues with chicken. I suspect my body was not used to the grease, and that taco bell had particularly greasy beef.

Taco bell plays nice for me.

On the other hand, last time I took my family to Chipotle, my kid had liquid poo for 2 weeks with onset a couple hours after eating there. We have never been back since. That place scares the you know what out of me.

You're in a lot more danger of GI infection from fresh produce as in the Chipotle condiments than you are from highly processed, standardized, frozen & reheated fast food.