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What Makes a Fart?

Did you know that no two farts are exactly alike? It's true. Farts are sort of like snowflakes in that regard.

Did you know that no two farts are exactly alike? It's true. Farts are sort of like snowflakes in that regard. Little, invisible, smelly, snowflakes.

While everybody past the age of 10 is well-versed in the manifold variety of farts and their associated sounds and smells and sensations and sobriquets, precious few of us know anything at all about the sources of their great diversity. Can you, for instance, explain the lingering piquancy of the "hot fart" in any greater scientific detail than "that one was spicy"? I can't. And that's sad. In order to rectify this egregious oversight by the American public school system and get the straight poop on the basics of butt-gas, I had a little sit down with Dr. Lester Gottesman, a proctologist from St. Luke's Roosevelt who bears an uncanny resemblance to Jerry Springer.


Vice: Hi, Dr. Gottesman. So we're here today to talk about farts.
Dr. Gottesman: Yes, I suppose we are.

What's up with the wide variety of noises farts make? Why do some come out as squeakers and others like a diesel truck going up a mountain?
The kinds of flatulence are directly related to the amount of swallowed air and the ability of the intestine to degrade food stuff to gas. It also has to do with the shape of the sphincter when the gas is released. If the sphincter is tight, it will make a different noise than if it's more relaxed.

Often times my farts feel physically hot. What causes that sensation?
The sensation of heat is when the internal sphincter opens a little to sample what's in the rectum. That is a normal response. If there isn't a great deal of gas, the body will expel it slower, allowing you to feel the fart's heat. If there is a lot of gas, the gas comes out too quickly for the body to feel the heat.

Is the temperature of the slow, hot farts actually higher than the quick, cool ones?
The temperature should be the same. Again, it is a product of the amount and speed in which one expels gas.

What's the reason behind the smell?
The smell has to do with the amount of absorbed products like methane, which is made by fermentation of what we eat, and that's what causes the bad smell, basically. As a baby, when you're born, passing through the vagina, you're infected by the bacteria in your mother's colon, and that's the bacteria you're dealt for your lifetime. Also, everybody is different in how they'll digest wheat products, milk products, whatever. And if they are not digested properly there will be a lot of methane produced and a lot of acid, and that would tend to cause a stinkier bowl movement.


Wait, go back to that thing about the vagina.
A baby is born with a sterile intestinal track. During the delivery, there's lots of fluid and stool and whatever, and it's thought that at that exposure the baby's colon is populated by the mother's colon bacteria, thereby affecting the smell of the individual's farts for the rest of their lifetime. There's also other theories claiming the colon is populated during the first few months of exposure to fecal material, but that probably doesn't affect the smell as much as the initial intake of feces by the baby during delivery.

Wow. It's like original shit sin. Does what your mother ate prior to delivery effect the bacteria you get?
Yes. In fact, they now also think that the appendix keeps an arsenal of bacteria so that if, for whatever reason, the bacteria in your colon gets killed by antibiotics the appendix can repopulate your colon with the bacteria that you've had since birth. That's the new thought as to why the appendix is around.

So the signature smell of your farts wholly depends on how much poop your mom had at the time…
It's not the amount, just the type of bacteria.

OK, but that's really what determines your fart smell forever?
Well, there are also other components. Farts are made by two things. They are made by one, the amount of air you swallow--so people who drink a lot of soda, chew a lot of gum, suck on candies, they get a lot of air into their colon, and that air comes out in farts. The second component is gas production by the colon. The colon's job is to break down the nutrients in food products, like proteins and fats and sugars, and in the process of breaking them down they produce either sulfur or methane, neither of which smell great. If, let's say, the colon has stuff in it like grapes and beans, and if it's just sitting there for a few days it's just going to ferment more and more until it becomes very smelly, versus if what you eat goes through quickly--like if you had the same beans, but it came out eight hours later, you'll tend not to have as much gas from those beans. So it has to do with what your intestinal transit is. For most people, it takes 32 hours from the time they eat something to the time they shit something. That's the average, so that means there are people who move their bowels every three or four days, and they have more time for the beans to ferment in the colon, thereby producing larger amounts of gas and more frequent, smellier spasms of gas.


What's the correlation between the increased level of farts and drinking beer or coffee?
Well, beer is carbonated, so that's why it makes you fart. Coffee causes the sphincter muscles to relax just a little bit, so you tend to have more farts by accident if you're drinking something with caffeine than if you aren't.

A lot of times when I wake up really early I have worse gas than when I wake up later in the day. Does that happen to a lot of people or just me?
You have worse gas early in the morning?

Yeah, like, if I wake up at six for whatever reason, I'll be a lot gassier for the first couple of hours I'm awake than if I wake up at nine or so.
When do you move your bowels?

First thing in the morning.
Do you have a lot of gas with the bowel movement?

I do, but what I'm trying to explain is if I wake up at my normal time I don't have that much gas, but if I wake up really early, whether or not I take a crap, I'll still have a ton of gas that goes along with it.
Well, it's possible the gas is being metabolized more by your the later you sleep. If you get up at six and take a dump at that time, the colon hasn't had as much time to metabolize, so what's coming out is incomplete, metabolized gas. That may be your answer, but honestly I've never heard of this before.

Well, that's disconcerting. Now, I imagine that you're familiar with "oops poops."
No, what's that?

It's when you think you're going to fart, but then a little bit of poop comes out.
Oh, OK, sure.


What I've noticed is, often when it happens it's not preceded by the urge to shit—it just feels like it's going to be a regular fart. Does that have anything to do with poop speed or its position in the intestines or anything?
No, it has to do with the muscles of the anus. There are two muscles of control. One muscle, the internal muscle which is active all the time, it's the one that allows you to sit on that chair without shitting on the chair, then you also have the external muscle which is a voluntary muscle like your biceps. And when you need to hold stool in it will contract, and keep the stool on the inside. The passage that you are describing happens for one of several reasons. One is that the internal muscle has become very labile, meaning any little input inside the anus causes it to relax. Sometimes it relaxes too much, and that can cause stool to slip out. The other reason is you could have hemorrhoids—everybody has hemorrhoids, but people with bigger hemorrhoids sometimes experience gas slipping out between the hemorrhoids and taking with it mucus material produced by the hemorrhoids, which can cause staining of your underwear.

That is shockingly gross. How long is gas in our body before it comes out?
About 30 hours. It has to go through five feet of large intestine, and 25 feet of small intestine.


This is an anal probe. The whole black part of the rod goes in.

Where does the differentiation between burps and farts occur? Why does some gas come out of your mouth vs. your ass?
It has to do with the configuration and the tone of muscles in your stomach. If you drink a whole lot of liquid with bubbles quickly, if you take one of these [picks up a can of diet Pepsi] and down it quickly there will be so much gas produced that the gas will need to go someplace, and the best place to go is to come back up. If you're drinking a small amount, then it has time to work its way through the small intestine and get to the large intestine, at which point the body starts fermenting it.


OK, while I've got you here, what's the strangest thing that you've seen up a butt?
Oh, a little of everything—beer bottles, milk bottles, every can of vegetable known to man.

Have you ever seen a beer bottle that broke up there?
No, they tend to stay together, beer bottles are fairly strong. I've also seen balloons, condoms, toys with the batteries still working.

Do those people waddle in?
Well, they usually wait until the middle of the night because they don't want to be seen, and occasionally we have to operate on them.

Do you see more girls or guys with stuff stuck up there?
More girls than I would have imagined, but mostly guys—mostly gay guys. I've also had people who want me to operate on their anuses to make their fart sounds a little more appealing.


Get the fuck out of here. What kind of a fart sound are they going for?
Generally they have a higher pitched sound, and they want something with a lower pitch.

Like a baritone versus a squeaker?
Basically. So I had to configure their anus skin so their fart sound would be more to their pleasing.

Oh shit, you actually did it? Someone paid you to make their farts sound better.
Well they tried to put it through with their insurance.

Which insurance company is willing to pay for that?
None, so far all the companies have denied it. But the people try and then they end up having to pay for it.

Any other weird stuff going on?
A lot of the gay guys I see do things like fisting and double fisting—you name it they do it. So you always have to be on your toes as to what they've potentially done to end up in the situation they're in. I've had a patient, he was on crack, of course, but he put a pogo stick on the steps, and he shot it straight up his ass and messed up his colon and prostate.


Oh dear god please tell me you're joking.
Nope. Another case that comes to mind is a woman who took an egg whisk and put it up her husband's butt, and that made a bad mess. Usually, for the majority of these accidents, people are on crack or coke.

Did you enjoy this article? Sure you did. Want to read more about farts and shit? Yeah you do.

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