I absolutely love spicy food, and it’s never affected my gut. I was actually confused when I read about people getting the shits after a curry and wondered if it was a joke. I’ve had curries so hot it caused people to recoil into a coughing and sweating fit after they dipped their finger in and had a taste and I have one every other day. I feel the burning in my mouth, my face turns red, my forehead sweats, my esophagus feels weird, but (tmi I know lol) when I go to the toilet I’m completely fine. no gut pains either.
There’s a few factors.
First is genetics. Not everyone has the same base level reaction to peppers and/or capsaicin. And it can be either of them causing intestinal rebellion. Some people just don’t respond well to even sweet peppers.
Second is habitation. The more spicy stuff you eat in general, the more your body adapts to it.
But, there’s also variances in mucosa. Our guts, the colon in specific, opportunists produce snot. It’s essentially the same as what coats your throat and sinuses. Not exactly the same, but the same basic ingredients and purpose. Separate from how you respond to the food, and how used to it you are, some people produce more than others.
In your case, I suspect that you have a higher resistance genetically, and produce mucous in your gut that protects you from the irritants that spicy foods have.
If you also have a healthy gut biome going, it’ll add a layer of resistance to things being over stimulated.
And that’s what causes the diarrhea and cramping for most people. The chemicals irritate tissues, so your body treats or like an emergency. That means to increase bowel motility and flush the guts with water. Which means squiiirt.