Not that this has ever happened to me ( I NEVER fart) When you have to fart and hold it in, what happens to it?

The gas stays in your colon. Once the peristaltic wave passes, the gas is allowed to move proximally (backward) to decompress the rectum. Sooner or later peristalsis will attempt to push it back out again.

To the extent that the gas contains air (which varies by diet and eating habits), some of the nitrogen and oxygen might be resorbed by the intestinal walls.

Three cheers for sphincter control.

LOL, thanks professor!!

I should have quit while I was ahead: My second paragraph above is incorrect (or should I say it stinks, or I'm full of beans, or... .

As bacterial gas from fermentation is added to swallowed air already present, nitrogen gets diluted; as its partial pressure falls then more nitrogen diffuses into the colon from the bloodstream to maintain equilibrium. Meanwhile the colonic flora consume any oxygen diffusing into the intestines.

Source: A Digest of Digestion by HW Davenport, Chapter 15: "Gas in the Gut."

LOL, Kitty. Now, I understand why they say on here that no question is a stupid question.

Professor, good answer. I didn't know that.

quote:

Originally posted by honilov:
Now, I understand why they say on here that no question is a stupid question.

"There are no stupid questions, just stupid answers."

Good link, clare.

LOL Clare...everything you ever wanted to know about farts and then some!!!

quote:

There are two kinds of farts: yours and everyone else's.

--Old proverb, possibly attributable to Roman senator Flatus Maximus.

Nothing like a little bathroom humor to heighten the allure of AnswerPool.

Prof, I think that Flatus Maximus's saying must have lost something in the translation it actually should read "There are two kinds of farts: Those that smell and your own".