How are we able to drink hot liquids, yet if that very same liquid spilled on our hand, it would hurt like crazy? Is there some kind of “internal AC” in our mouths?

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How are we able to drink hot liquids, yet if that very same liquid spilled on our hand, it would hurt like crazy? Is there some kind of “internal AC” in our mouths?

In: Biology

The tissues are different, both in terms of nerve-endings and thickness. Furthermore, there’s saliva in your mouth (hopefully) that coats your throat and cheeks. Also, our oral orifices go thru a different kind of repetitive abuse than most areas on our bodies, but if we abused other parts of our skin, they too would lose sensitivity (think martial artists with calluses and grandmas that have burnt the shit out of their fingers over and over).

Also, hot liquids are usually sipped and/or slurped. In sipping, only a small amount is ingested at a time, and this mixes with the saliva in your mouth, instantly cooling it. When slurping, air in introduced with the liquid, allowing a degree of instantaneous evaporation.

Personally, my hands are significantly more temperature resistant than my mouth is. Years of working with molten plastic will do that.

You can easily build tolerance to temperature; at least when it’s short of actually damaging tissues.

You’re also not drinking a lot of fluid at a time, and it’s in motion so spreads the heat across more tissue. Spills are bigger and don’t go anywhere so all the heat is dumped in one place. Take a huge gulp of a hot beverage, hold it in your mouth, and you will rapidly notice you have burned your mouth.

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There’s a shitload of blood flow to the surface of the mouth tissue to act as a heat exchanger. And either way, when you sip a hot liquid, it immediately spreads out over whatever surface it touches, forming a thin layer that loses heat very quickly.

I can’t, and I’ve never understood how people can. Hot liquids in my mouth hurt just as much, if not more, than if they were spilled on my hands