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You're basically right yeah! Milk has casein which binds with the capsaicin and drags it away into your gut

Thank you for your reply. I'll look into casein bonding with the capsaicin. Do you happen to know what the body's receptor are called?

I thought it was the fat content because the capsaicin isn't water soluble. I've read that eating spicy foods in hot places is useful for humans, something like preventing dehydration or helping prevent overheating I can't quite recall.

I'm sure it has lots of happy benefits for us, but I doubt it evolved for that reason!

Fat is directly involved in the casein, but I can't remember how without googling and I'm lazy. I think the casein is in the fat or something?

Casein is the protein in milk, I figured they didn't evolve for that but perhaps that why they've been adopted.