//The Facts About Flatulence// by Margaret C. McDonald. Nov/19/1990 \\
[From a old BBS file, original source unknown.]

<blockquote>

Ever since my hearthmate banned me from eating black bean
soup, I've been wanting to know the facts about flatulence. Why
are some, uh, emissions appropriately labeled "silent but
deadly"? Why do others cause great auditory but not olfactory
embarrassment? To get answers I turned to Pitt
gastroenterologist David H. Van Thiel, M.D., who promptly armed
me with Chapter 19 of the textbook Gastrointestinal Disease,
titled simply "Intestinal Gas." Between it and the good doctor,
I am now the office expert on this awkward but interesting
subject.

According to chapter authors Michael D. Levitt, M.D., and
John H. Bond, M.D., "...Medical literature concerning bowel gas
is relatively long on subjective impressions and short on
scientific data." Some of the impressions, however (like the
one about black beans), turn out to have good physiologic
explanations. Here's what I learned.

Most of us pass somewhere between 200 and 2,000 ml of gas
per day (average, about 600 ml) in roughly 13-14 passages.
These emissions are composed of five gasses: nitrogen (N2),
oxygen (O2), carbon dioxide (CO2), hydrogen (H2), and methane
(CH4). Nitrogen usually predominates, followed by variable
concentrations of carbon dioxide, hydrogen, and methane, and
very low levels of oxygen. Gas gets into our guts by air
swallowing (which accounts for very little), production within
the bowel and colon (which accounts for a lot), and diffusion
from the blood. As far as those who study these things can
figure out, most air that is swallowed comes out the way it
went in: it is belched or "eructed," as the textbook informed
me. Most of the nitrogen is accounted for by diffusion from
blood to bowel; it may give flatus some of its bang but little
of its bite.

We are more interested in the gases produced in the bowel's
interior space or lumen -- the carbon dioxide, hydrogen, and
methane (all of which are negligible in the atmosphere). These
gases accumulate when the digestive system's assortment of
resident bacteria, acting like microscopic gas factories, begin
the task of digesting our latest meal. It is unclear whether
carbon dioxide is a direct or indirect product of bacterial
metabolism, but CO2 can account for up to 50%-60% of the gas in
flatus, usually in association with hydrogen, which is
definitely a product of bacterial fermentation. Methane, too,
is exclusively a bacterial leftover. However, to make the H2
and CH4, the bacteria need what Levitt and Bond call "exogenous
fermentable substrates" -- in English, that's carbohydrate and
protein. And here's where the science becomes useful in
answering my questions.

"Gas is basically produced by foods that have undigestible
or excess carbohydrates, which are not absorbed when they get
to the colon, explains Van Thiel."  Beans, for example, have
complex carbohydrates that are maldigested. And the same holds
true for mushrooms. Many people don't realize that mushrooms
contain a unique sugar called raffinose, which humans can't
break down. Cabbages and onions do the same thing.  "As a group,
vegetarians produce more gas than meat-eaters because the
intestinal enzymes can't digest the cellulose in vegetables'
cell walls. However, the colon's bacteria relish the stuff. The
outcome: When a group of young men, in the service of science,
feasted on a diet rich in pork and beans, their flatus
elimination increased from 15 ml to 176 ml per hour!"

Great, so this is where the gas comes from. But what about
the odor, the noise, the frequency -- the embarrassing stuff?
The amount and odor of flatus, says Van Thiel, are largely
accounted for by the type of bacteria we have in our guts.
Newborn infants and germ-free rats have no intestinal bacteria,
although the infants acquire them almost immediately. "Unless
you're hermetically sealed, which is essentially what those
germ-free rats are, you take in bacteria within hours of being
delivered; and they immediately begin to replicate in the
advantageous environment of the intestinal system. And it
appears as if the kind of bacteria you acquire in your neonatal
life basically persist with you."  While the bacteria that make
up the intestinal flora are generally the same in everyone,
"that's like saying people are generally the same," says Van
Thiel. They do the same job but in their own way.

The reason this is important is that different bacteria
digest different kinds of carbohydrates. Some make more
methane; others help hydrogen to combine with sulfur (from
other foods or water) to make hydrogen sulfide. According to
Levitt and Bond, only about one-third of us excrete CH4, a
capability that, again, seems to depend on the bacteria
floating around us at birth. There's an easy way to determine
whether you produce methane or not: if you do, your stools will
float. This is because CH4 gets trapped in the stool, making it
less dense than water. Better the relatively odorless methane,
however, than hydrogen-sulfide, which has the unavoidable odor
of rotten eggs. "The only notable fact about methane is that it
burns with a blue flame," says Van Thiel, "and that's why crazy
college kids who like to, uh, ignite their flatus have to be
methane producers. And those who make more methane are more
like flamethrowers than those who don't."

That answers the odor question, but what about the noise?
"What makes the loud ones?" I asked the accommodating
gastroenterologist. The loud ones are basically a function of
three things, he told me: the volume of gas, the force with
which it is expelled, and the presence of hemorrhoids or other
anatomical features that could resonate. "People with large
hemorrhoids, for example, will have louder flatus than people
with lax sphincters. Vegetarians, who actually pass a lot of
gas, frequently have quiet, frequent flatus because they have
large, bulky stools and looser sphincters. They will be
detected socially only if it's foul-smelling; whereas,
carnivores may have less gas but, since they have tighter
sphincters and may be more constipated, have high drama
flatus."

So what's to be done if we wish to alter our flatulence
profiles? Paradoxically, studies show that many people who
complain of discomfort from "too much gas" have essentially the
same gas volume and composition as normal controls. However,
they seem to suffer from disordered intestinal motility, with
more gas being refluxed back into the stomach, as well as an
abnormal pain response to bowel distention. While
anticholinergic agents have been prescribed for this problem,
their efficacy has not been proven. Thus, the path of least
resistance is to stop eating the offending foods.

The same advice is good for those who complain of frequent
or excessive flatus. If much of the excreted gas is composed of
hydrogen and carbon dioxide, which originate in the body, not
the air, the problem may be a general malabsorption disorder or
difficulty with particular foods. A low carbohydrate diet will
often turn down the flatus volume.

In addition to the beans, mushrooms, onions, celery, and
other foods containing complex carbohydrates and undigestible
fiber, many patients with abdominal complaints also benefit
from reducing their intake of lactose, the milk sugar in dairy
products. Most adults lack, to some degree, the enzyme needed
to digest lactose. "As long as you eat an amount below your
tolerance threshold, you're asymptomatic," says Van Thiel. "If
you go above your threshold, then you have gas, cramps, and
diarrhea." Another culprit may be the sorbitol in diet foods
like candy, chewing gum, and sugar-free lozenges. Sorbitol is
another non-digestible carbohydrate; but, because of its form,
people have a harder time making the association between
consumption and later discomfort.

At this point I'm thinking, "Well, I don't want to stop
being a vegetarian. I like cheese, and onions are a necessity.
Maybe I can take some medicinal pesticide to kill my intestinal
flora and recultivate with a less obnoxious set." Wrong, says
Van Thiel. Even the strongest antibiotics won't seek and
destroy all of the 107 to 1015 bacteria in my distal small
intestine and colon; and I'm likely to make myself very sick in
the process. Thus, after my journey into the dark recesses of
my bowel, I can only come up with one solution: make sure that
when I dine on black bean soup I dine alone.

</blockquote>


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[[https://www.menshealth.com/health/a22789684/does-farting-burn-calories/?utm_source=kpaddock.com/fart|How many calories does a fart burn?]]

{{:resources:mh-turtle-fart-1524498617.jpg?400|https://www.menshealth.com/health/a22789684/does-farting-burn-calories/?utm_source=kpaddock.com/fart}}

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See also:

  * [[http://al-hikmah.org/step-on-gas-fighting-flatulence.htm|Step on the gas: fighting flatulence]]: Which will give you excess gas - a bowl of beans, a glass of soda, or a stick of gum? It could be all of the above! Here's how you can fight flatulence.
  * [[http://www.flat-d.com|Flatulence Deodorizer]] {I've never needed to use it, so please don't consider this an endorsement for it. ;-)}; See also: [[http://worldwide.espacenet.com/publicationDetails/biblio?DB=worldwide.espacenet.com&II=0&ND=3&adjacent=true&locale=en_EP&FT=D&date=20011106&CC=US&NR=6313371B1&KC=B1|Patent #US6313371 (B1) - 2001-11-06]]
  * [[http://theweek.com/speedreads/index/264585/speedreads-study-smelling-farts-is-good-for-your-health|Study: Smelling farts is good for your health]]
  * [[http://www.exeter.ac.uk/news/research/title_393168_en.html|Rotten egg gas holds key to healthcare therapies]]: It may smell of flatulence and have a reputation for being highly toxic, but when used in the right tiny dosage, hydrogen sulfide is now being being found to offer potential health benefits in a range of issues, from diabetes to stroke, heart attacks and dementia.
  * [[http://www.ncbi.nlm.nih.gov/pubmed/24755204|AP39, a novel mitochondria-targeted hydrogen sulfide donor, stimulates cellular bioenergetics, exerts cytoprotective effects and protects against the loss of mitochondrial DNA integrity in oxidatively stressed endothelial cells in vitro.]]

~~DISCUSSION~~

{{tag>bbs fart flat-d flatus flatulence constipated sphincter nitrogen N2 oxygen O2 carbon dioxide CO2 hydrogen H2, and methane CH4}}