Everybody farts. Here are some interesting facts and information about farts.
About the word "fart":
Fart is an English language vulgarism most commonly used in reference to flatulence. The word "fart" is generally considered unsuitable in a formal environment by modern English speakers, and it may be considered vulgar or offensive in some situations. Fart can be used as a noun or a verb. The immediate roots are in the Middle English words ferten, feortan or farten; which is akin to the Old High German word ferzan. Cognates are found in old Norse, Slavic and also Greek and Sanskrit. The word "fart" has been incorporated into the colloquial and technical speech of a number of occupations, including computing.
The English word fart is one of the oldest words in the English vocabulary. Its Indo-European origins are confirmed by the many cognate words in other Indo-European languages: It is cognate with Greek πέρδομαι (perdomai), Latin pēdĕre, Sanskrit pardate, Avestan pərəδaiti, and Russian пердеть (perdet'), Polish "pierd" & as the German cognate furzen also manifests.
What is a fart?
Flatulence is the production of a mixture of gases in the digestive tract of mammals or other animals that are byproducts of the digestion process. Such a mixture of gases is known as flatus, (informally) fart, or simply gas, and is expelled from the rectum in a process colloquially referred to as "passing gas" or "farting". Flatus is brought to the rectum by the same process which causes feces to descend from the large intestine. The noises commonly associated with flatulence are caused by the vibration of the anal sphincter, and occasionally by the closed buttocks.
So what's in a fart?
Nitrogen, the main constituent of air, is the primary gas released during flatulence, along with carbon dioxide which is present in higher quantities in those who drink carbonated beverages regularly. The lesser component gases methane and hydrogen are flammable, and so flatus containing adequate amounts of these can be ignited. However, not all humans produce flatus that contains methane. For example, in one study of the faeces of nine adults, only five of the samples contained archaea capable of producing methane. Similar results are found in samples of gas obtained from within the rectum.
The gas released during a flatus event frequently has an unpleasant odor which mainly results from low molecular weight fatty acids such as butyric acid (rancid butter smell) and reduced sulphur compounds such as hydrogen sulphide (rotten egg smell) and carbonyl sulphide that are the result of protein breakdown. The incidence of odoriferous compounds in flatulence emissions increases from herbivores, such as cattle, through omnivores to carnivorous species, such as cats. Such odor can also be caused by the presence of large numbers of microflora bacteria and/or the presence of faeces in the rectum.
The major components of the flatus, which are odorless, by percentage are:
Nitrogen - 20% - 90%
Hydrogen - 0% - 50%
Carbon Dioxide - 10% - 30%
Oxygen - 0% - 10%
Methane - 0% - 10%
How does a fart happen?
The sound varies depending on the tightness of the sphincter muscle and velocity of the gas being propelled, as well as other factors such as water and body fat. The auditory pitch (sound) of the flatulence outburst can also be affected by the anal embouchure. Among humans, flatulence occasionally happens accidentally, such as incidentally to coughing or sneezing or during orgasm; on other occasions, flatulence can be voluntarily elicited by tensing the rectum or "bearing down" and subsequently releasing the anal sphincter, resulting in the expulsion of a flatus.
Flatus is brought to the rectum by the same process which causes feces to descend from the large intestine, and may cause a similar feeling of urgency and discomfort. Nerve endings in the rectum usually enable individuals to distinguish between flatus and feces, although loose stool can confuse the individual, occasionally resulting in accidental defecation.
What causes us to fart?
Intestinal gas is composed of varying quantities of exogenous sources (air that is ingested through the nose and mouth) and endogenous sources (gas produced within the digestive tract). The exogenous gases are swallowed (aerophagia) when eating or drinking or increased swallowing during times of excessive salivation (as might occur when nauseated or as the result of gastroesophageal reflux disease). The endogenous gases are produced either as a by-product of digesting certain types of food, or of incomplete digestion. Anything that causes food to be incompletely digested by the stomach and/or small intestine may cause flatulence when the material arrives in the large intestine due to fermentation by yeast or prokaryotes normally or abnormally present in the gastrointestinal tract.
Flatulence-producing foods are typically high in certain polysaccharides (especially oligosaccharides such as inulin) and include beans, lentils, dairy products, onions, garlic, scallions, leeks, turnips, rutabagas, radishes, sweet potatoes, potatoes, cashews, Jerusalem artichokes, oats, wheat, yeast in breads, and other vegetables. Cauliflower, broccoli, cabbage, Brussels sprouts and other cruciferous vegetables that belong to the genus Brassica are commonly reputed to not only increase flatulence, but to increase the pungency of the flatus. In beans, endogenous gases seem to arise from complex oligosaccharide (carbohydrates) that are particularly resistant to digestion by mammals, but which are readily digestible by microorganisms (Methane producing archaea; Methanobrevibacter smithii) that inhabit the digestive tract. These oligosaccharides pass through the upper intestine largely unchanged, and when these reach the lower intestine, bacteria feed on them, producing copious amounts of flatus. In the case of those with lactose intolerance, intestinal bacteria feeding on lactose can give rise to excessive gas production when milk or lactose-containing substances have been consumed.
Interest in the causes of flatulence was spurred by high-altitude flight and the space program; the low atmospheric pressure, confined conditions, and stresses peculiar to those endeavours were cause for concern. In the field of mountaineering, High Altitude Flatus Expulsion was first noticed over two hundred years ago.
How often do we fart?
Most people produce about 1-3 pints a day and pass gas about 14 times a day.
What makes them stink?
The characteristic odor is attributed to trace gases such as skatole, indole, and sulfur-containing compounds.
An estimated 30-150 grams of this undigested food reach the colon in the form of carbohydrate every day. But this amount can vary with diet and how well your GI tract is functioning. The unpleasant odor often associated with flatus is generally attributed to trace sulfur-containing compounds, produced only by particular bacteria not found in everyone.
Farts in history and popular culture:
History has numerous anecdotal accounts of flatulence, including Hippocrates himself professing, "Passing gas is necessary to well-being." The Roman Emperor Claudius equally decreed that "all Roman citizens shall be allowed to pass gas whenever necessary." Unfortunately for flatulent Romans, however, Emperor Constantine later reversed this decision in a 315 BC edict.
In the mid-1800s flatulence took center stage with the French entertainer Joseph Pugol ("Le Petomane"). Pugol was able to pass gas at will and at varying pitch, thereby playing tunes for sold-out shows at the Moulin Rouge. Such was his success that lesser competitors began to appear, including the Spaniard "El Rey" and the female Angele Thiebeau (later revealed as a fake using hidden air bellows).
More recently, flatulence was immortalized by Mel Brooks in the movie Blazing Saddles with his bean-eating cowboys.