This might sound like a joke, but something I’ve always been curious about. Does eating spicy foods really put hair on your chest? If not, I’m curious as to where a phrase like that would come from. You can laugh if you’d like. I feel foolish for even asking.
I did a Google search for the phrase “put hair on your chest” and found that this idiom is use in many situations and many cultures. I really do not know the answer about where the phrase came from, but I did enjoy the threads as I searched for an answer. I hope you know that if anything really put hair on the chest, then it would be marketed as a cure for hair loss in some circles.
Somewhat related, here’s a list of other “hair” related idioms, from TheFreeDictionary.com.