Burping (also called belching and eructation) is the release of
gas from the upper
digestive tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...
(
esophagus
The esophagus (American English), oesophagus (British English), or œsophagus (Œ, archaic spelling) (American and British English spelling differences#ae and oe, see spelling difference) all ; : ((o)e)(œ)sophagi or ((o)e)(œ)sophaguses), c ...
and
stomach
The stomach is a muscular, hollow organ in the upper gastrointestinal tract of Human, humans and many other animals, including several invertebrates. The Ancient Greek name for the stomach is ''gaster'' which is used as ''gastric'' in medical t ...
) of animals through the
mouth
A mouth also referred to as the oral is the body orifice through which many animals ingest food and animal communication#Auditory, vocalize. The body cavity immediately behind the mouth opening, known as the oral cavity (or in Latin), is also t ...
. It is usually
audible
Audible may refer to:
* Audible (service), an online audiobook store
* Audible (American football), a tactic used by quarterbacks
* ''Audible'' (film), a short documentary film featuring a deaf high school football player
* Audible finish or ru ...
.
In humans, burping can be caused by normal eating processes, or as a side effect of other medical conditions. There is a range of levels of social acceptance for burping: within certain contexts and cultures, burping is acceptable and may even be perceived as humorous, while in others it is seen as impolite or even offensive and therefore unacceptable.
Humans are not the only animals that burp: it is very common among other mammals. In particular, burping by domesticated ruminants, such as cows or sheep, is a major contributor of
methane emissions
Increasing methane emissions are a major contributor to the rising concentration of greenhouse gases in Earth's atmosphere, and are responsible for up to one-third of near-term global heating. During 2019, about 60% (360 million tons) of methane r ...
and may
have a negative effect on the environment. Significant research is being done to find mitigation strategies for ruminant burping, e.g. modifying the animals' diets with ''
Asparagopsis taxiformis'' (red
seaweed).
Causes
*Burping is usually caused by
swallowing air when eating or drinking and subsequently expelling it, in which the expelled gas is mainly a mixture of
nitrogen
Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...
and
oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...
.
*Burps can be caused by drinking beverages that contain dissolved
carbon dioxide
Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...
, such as
beer
Beer is an alcoholic beverage produced by the brewing and fermentation of starches from cereal grain—most commonly malted barley, although wheat, maize (corn), rice, and oats are also used. The grain is mashed to convert starch in the ...
and
carbonated drinks; in these cases, the expelled gas is mainly carbon dioxide.
*Burping can be caused by swallowing air while consuming
chewing gum
Chewing gum is a soft, cohesive substance designed to be chewed without being swallowed. Modern chewing gum is composed of gum base, sweeteners, softeners/plasticizers, flavors, colors, and, typically, a hard or powdered polyol coating. Its tex ...
, sucking on
hard candy, talking while eating or drinking, or while smoking. It may also occur through swallowing air as a
habit.
*
Diabetes drugs such as
metformin and
exenatide can cause burping, especially at higher doses. This often resolves in a few weeks.
*Burping combined with other symptoms such as
dyspepsia
Indigestion, also known as dyspepsia or upset stomach, is a condition of impaired digestion. Symptoms may include upper abdominal fullness, heartburn, nausea, belching, or upper abdominal pain. People may also experience feeling full earlier ...
,
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat.
Over 30 d ...
and
heartburn
Heartburn is a burning sensation felt behind the breastbone. It is a symptom that is commonly linked to acid reflux and is often triggered by food, particularly fatty, sugary, spicy, chocolate, citrus, onion-based and tomato-based products. Ly ...
may be a sign of an
ulcer
An ulcer is a discontinuity or break in a bodily membrane that impedes normal function of the affected organ. According to Robbins's pathology, "ulcer is the breach of the continuity of skin, epithelium or mucous membrane caused by sloughin ...
or
hiatal hernia, and should be reviewed by a physician.
*Other causes of burping include
food allergies,
gallbladder
In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow Organ (anatomy), organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath t ...
diseases, ''
H. pylori'',
acid reflux disease and
gastritis.
Complications
In
microgravity
Weightlessness is the complete or near-complete absence of the sensation of weight, i.e., zero apparent weight. It is also termed zero g-force, or zero-g (named after the g-force) or, incorrectly, zero gravity.
Weight is a measurement of the fo ...
environments, burping is frequently associated with
regurgitation, known as wet burping. With reduced gravity, the stomach contents are more likely to rise up into the esophagus when the
gastroesophageal sphincter is relaxed, along with the expelled air.
Disorders
*Chest pain associated with burping can occur, but is rare.
*
Retrograde cricopharyngeal dysfunction (R-CPD) or retrograde upper esophageal sphincter dysfunction (R-UESD),
also called "abelchia", involves the
cricopharyngeus muscle not being able to relax, leading to inability to burp. R-CPD was first discovered in 1987,
and further research gained attention in the mid to late 2010s. Common symptoms include gurgling noises, bloating, and flatulence; lesser but common symptoms can be potentially painful hiccups, nausea, constipation, hypersalivation, or shortness of breath.
A
high-resolution manometry,
esophageal manometry or
fluoroscopy
Fluoroscopy (), informally referred to as "fluoro", is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a surgeon to see t ...
by an
ENT doctor is able to assess the issue.
80% of patients were successfully treated with
botox after a single injection. If the injection is unsuccessful, an alternative is partial
cricopharyngeal myotomy.
Society and culture
Acceptance
Some
South Asian cultures view burping as acceptable in particular situations. For example, a burping guest can be a sign to the host that the meal satisfied them and they are full.
In
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, burping during a meal is considered bad manners. Burping during a meal is also considered unacceptable in Western cultures, such as
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
and
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...
.
Despite virtually no scientific research on the subject, small online communities exist for burping as a
sexual fetish. Online, people of any
sexual orientation
Sexual orientation is an enduring personal pattern of romantic attraction or sexual attraction (or a combination of these) to persons of the opposite sex or gender, the same sex or gender, or to both sexes or more than one gender. Patterns ar ...
anecdotally report some attraction to burping, with what appears to be psychological and/or behavioural overlaps with other sexual fetishes including
body inflation,
feedism,
vorarephilia
Vorarephilia (often shortened to vore) is a paraphilia characterized by the erotic desire to be consumed by, or to personally consume, another person or creature, or an erotic attraction to the process of eating in general practice. Soft vo ...
, and
farting fetishes.
Anecdotally, the 'loudness' aspect appears to be an important element to burp fetishists. Despite being a rather uncommon fetish, it continues to follow a general well-known pattern of sexual behaviour where hearing influences sexual arousal and response, noting that "it is the noise made rather than the action itself that appears to be what is sexualized and/or interpreted by the fetishist as sexually pleasurable and arousing".
Infants
Babies are likely to accumulate gas in the stomach while feeding and experience considerable discomfort (and agitation) until assisted. Burping an infant involves placing the child in a position conducive to gas expulsion (for example against the adult's shoulder, with the infant's stomach resting on the adult's chest) and then lightly patting the lower back. Because burping can cause
vomiting
Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...
, a "burp cloth" or "burp pad" is sometimes employed on the shoulder to protect clothing.
World record
The
Guinness World Record for the loudest burp was 112.4
dB, set by Neville Sharp from
Darwin, Australia in 2021. This is approximately as loud as a
jet engine
A jet engine is a type of reaction engine, discharging a fast-moving jet (fluid), jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition may include Rocket engine, rocket, Pump-jet, water jet, and ...
at . The record was previously held by Paul Hunn, who held the record for 12 years.
Burped speech
It is possible to voluntarily induce burping through swallowing air and then expelling it, and by manipulation of the
vocal tract
The vocal tract is the cavity in human bodies and in animals where the sound produced at the sound source (larynx in mammals; syrinx in birds) is filtered.
In birds, it consists of the trachea, the syrinx, the oral cavity, the upper part of t ...
produce burped speech.
While this is often employed as a means of entertainment or competition, it can also act as an alternative means of
vocalisation for people who have undergone a
laryngectomy, with the burp replacing laryngeal
phonation
The term phonation has slightly different meanings depending on the subfield of phonetics. Among some phoneticians, ''phonation'' is the process by which the vocal folds produce certain sounds through quasi-periodic vibration. This is the defi ...
. This is known as
esophageal speech.
Other animals
Many other
mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...
s, such as
cows,
dogs and
sheep
Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to d ...
, also burp.
Ruminants
Much of the gas expelled is produced as a
byproduct of the ruminant's
digestive process. These gases notably include a large volume of
methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes ...
, produced exclusively by a narrow cohort of
methanogen
Methanogens are anaerobic archaea that produce methane as a byproduct of their energy metabolism, i.e., catabolism. Methane production, or methanogenesis, is the only biochemical pathway for Adenosine triphosphate, ATP generation in methanogens. A ...
ic
archaea
Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even thou ...
in the animal's gut; ''
Escherichia coli
''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...
'' (''E. coli'') and other bacteria lack the enzymes and cofactors required for methane production. A lactating cow produces about 322g of methane per day, ''i.e.'' more than 117 kg per year through burping and exhalation, making commercially farmed cows a major (37%) contributor to anthropogenic
methane emissions
Increasing methane emissions are a major contributor to the rising concentration of greenhouse gases in Earth's atmosphere, and are responsible for up to one-third of near-term global heating. During 2019, about 60% (360 million tons) of methane r ...
, and hence to the
greenhouse effect
The greenhouse effect occurs when greenhouse gases in a planet's atmosphere insulate the planet from losing heat to space, raising its surface temperature. Surface heating can happen from an internal heat source (as in the case of Jupiter) or ...
. 95% of this gas (wind) is emitted through burping. This has led scientists at the
Commonwealth Scientific and Industrial Research Organisation
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is an Australian Government agency that is responsible for scientific research and its commercial and industrial applications.
CSIRO works with leading organisations arou ...
of
Perth
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The ...
,
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
, to develop an anti-methanogen vaccine to minimize methane in cow burps.
One reason why cows burp so much is that they are often fed foods that their digestive systems cannot fully process, such as
corn
Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout Poaceae, grass that produces cereal grain. It was domesticated by indigenous peoples of Mexico, indigenous peoples in southern Mexico about 9,000 years ago ...
and
soy. Some farmers have reduced burping in their cows by feeding them
alfalfa
Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial plant, perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, ...
and
flaxseed, which are closer to the grasses that they had eaten in the wild before they were domesticated.
Birds
There is no documented evidence that birds burp, though
ornithologist
Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", is a branch of zoology dedicated to the study of birds. Several aspects of ornithology differ from related discip ...
s believe that there is nothing which physiologically prevents them from doing so. However, since the
microbiota of birds do not include the same set of gas-producing bacteria that mammals have to aid in digestion, gas hardly builds up in the
gastrointestinal tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...
s of birds.
See also
*
Flatulence
Flatulence is the expulsion of gas from the Gastrointestinal tract, intestines via the anus, commonly referred to as farting. "Flatus" is the medical word for gas generated in the stomach or bowels. A proportion of intestinal gas may be swal ...
*
Hiccup
A hiccup (scientific name singultus, from Latin for "sob, hiccup"; also spelled hiccough) is an spasm, involuntary contraction (myoclonic jerk) of the diaphragm (anatomy), diaphragm that may repeat several times per minute. The hiccup is an in ...
* ''
Penelope and the Humongous Burp''
References
External links
{{Digestive system and abdomen symptoms and signs
Reflexes
Symptoms and signs: Digestive system and abdomen