Interesting facts on farts...
How does a fart travel to the anus? (Question submitted by Sigfrido H.)
One may wonder why fart gas travels downward toward the anus when gas has a lower density than liquids and solids, and should therefore travel upwards.
The intestine squeezes its contents toward the anus in a series of contractions, a process called peristalsis. The process is stimulated by eating, which is why we often need to poop and fart right after a meal. Peristalsis creates a zone of high pressure, forcing all intestinal contents, gas included, to move towards a region of lower pressure, which is toward the anus. Gas is more mobile than other components, and small bubbles coalesce to from larger bubbles en route to the exit. When peristalsis is not active, gas bubbles may begin to percolate upwards again, but they won't get very far due to the complicated and convoluted shape of the intestine. Furthermore, the anus is neither up nor down when a person is lying down.
Why do farts come out of your butt? (Question submitted by the Perry family)
The butt is the location of the anus in humans, and by definition, a fart is an anal escape of intestinal gas. We should be grateful that we are not crinoids. The crinoid is a marine creature with a U-shaped gut, and its anus is located next to its mouth.
Is it true that some people never fart? No, not if they're alive. People even fart shortly after death.
At what time of day is a gentleman most likely to fart? (Submitted by David)
A gentleman is mostly likely to fart first thing in the morning, while in the bathroom. This is known as "morning thunder," and if the gentleman gets good resonance, it can be heard throughout the household.
Is a fart really just a burp that comes out the wrong end? No, a burp emerges from the stomach and has a different chemical composition from a fart. Farts have less atmospheric gas content and more bacterial gas content than burps.
Is it harmful to hold in farts? There are differences in opinion on this one. Certainly, people have believed for centuries that retaining flatus is bad for the health. Emperor Claudius even passed a law legalizing farting at banquets out of concern for people's health. There was a widespread belief that a person could be poisoned or catch a disease by retaining farts.
Doctors I have spoken to recently have told me that there is no particular harm in holding in farts. Farts will not poison you; they are a natural component of your intestinal contents. The worst thing that can happen is that you may get a stomach ache from the gas pressure. But one doctor suggested that pathological distention of the bowel could result if a person holds in farts too much. And Dr. P. said that the effort involved in retaining flatus can cause hemorrhoids.
Where do farts go when you hold them in? How often have you held in a fart, intending to release it at the first appropriate opportunity, only to find that the fart has disappeared when you are ready for it?
I asked several doctors where the fart goes. Does it leak out slowly without the person knowing it? Is it absorbed into the bloodstream? What happens to it?
The doctors agree that the fart is neither released nor absorbed. It simply migrates back upward into the intestine and comes out later.
It is reassuring to know that such farts aren't really lost, just delayed.
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