Why do some farts feel so hot?

They can’t be more than 98.6 degrees, right? Yet we’ve all had moments in our lives when it feels like flames are shooting out of our ass. How is that possible?

I don’t know for sure, but my guess would be it’s a chemical heat that depends largely on what you ate. The “hotter” ones generally also smell worse, which indicates there’s definitely some chemical composition in there causing them to feel hot in the same way spicy foods seem to burn in the mouth … and on the exit trip.

The human body is not uniformly 98.6 degrees Fahrenheit. That’s just what an average number of people register when their temperature is measured sub-lingually. Rectal temperature, for instance, is slightly higher, while auxillary (armpit) temperature is slightly lower. Those are the accessible locations. The middle of the gut is bound to be warmer still.

So, two reasons for farts of fire:

  • the gas expelled was in the middle of the gut long enough to warm up to internal body temperature and then was sent along quickly enough that it is comparatively warm in comparison to the anus.

  • capsaicin, the chemical present in peppers, is not affected by digestive juices. So, what gives your mouth that hot’n’spicy feeling on the way in does the same on the way out.

An ex-coworker of mine used to have a favorite joke predicated on this theme… A man loses a contest eating five-alarm hot wings at at a bar, and learns from the winner the valuable tip of using vanilla ice cream as a buffering agent (“for every wing you eat, take a lick of that ice cream cone”). It ended with the punch line of the man’s roommate hearing him yelling from the bathroom the next day: “Come on, ice cream! Come on!”

**Why do some farts feel so hot? **

I have just added this to my list of “Ten Worst Pickup Lines”.

Because people do this?


If only someone had explained this to me years ago as the rationale behind the “eat a bland diet” rule when you have stomach flu. This should not be a lesson one has to learn from cruel experience.

I think you meant to type axillary temperature (armpit = axilla).
Good explanation.

I don’t accept that this could make the difference. All gas has to come through the gut and all would be at internal body temperature. The density of gas is so low that it very quickly becomes the same temperature as its environment when in a small space. I should think it would take seconds to reach the temperature of the gut surrounding it, even were that to vary significantly.

Since when did anyone ever manage to learn from the mistakes of others? :dubious: