If you’ve ever tasted anything with alcohol
in it, you know that it can burn on the way down. In the extreme — like, if you down a shot
of everclear or something — it might even feel like your mouth and throat are being
scalded. Maybe your eyes start watering, and your nose
starts running… it was supposed to be a casual swig, and now all your fellow drinking-aged
friends are laughing at you. But there’s a good reason that alcohol burns
so much, and it has nothing to do with its actual temperature. Instead, that shot of tequila feels hot because
it’s messing with a type of heat receptor in your mouth and throat — specifically,
the receptor called VR1. When you taste something with a high temperature,
it triggers this receptor, which sends a message to your nerves that they’re detecting something
hot. That message then gets sent along to your brain, and you feel it as burning and
probably pain. Ethanol — the kind of alcohol that’s relatively
safe to drink — binds to those same receptors. And so does capsaicin, which you might know
as the stuff in spicy food that makes your mouth feel like it’s on fire. But capsaicin activates those receptors directly,
telling them that wow, that chili is REALLY HOT, whereas ethanol just makes them more
sensitive. Normally, your VR1 receptors activate at 42
degrees Celsius — in other words, anything warmer than 42 degrees feels hot. But ethanol lowers that threshold to just
34 degrees. And your body temperature? That’s around 37 degrees. So, suddenly, your body feels like it’s
burning you. Alcohol is just weird, people. So the next time you take a shot and your
eyes start watering, just remember: it’s not the booze that’s hot. It’s you. Thanks to Patreon patron Jeff Posey for asking
this question, and thanks to all our patrons, who keep these answers coming. If you’d
like to submit a question to be answered, just go to patreon.com/scishow. And don’t
forget to go to youtube.com/scishow and subscribe!