Defecation (or defaecation) follows

digestion Digestion is the breakdown of large insoluble food compounds into small water-soluble components so that they can be absorbed into the blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into th ...

and is the necessary biological process by which organisms eliminate a solid, semisolid, or liquid

waste Waste are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor Value (economics), economic value. A wast ...

material known as

feces Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the ...

(or faeces) from the

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 ...

via the

anus In mammals, invertebrates and most fish, the anus (: anuses or ani; from Latin, 'ring' or 'circle') is the external body orifice at the ''exit'' end of the digestive tract (bowel), i.e. the opposite end from the mouth. Its function is to facil ...

cloaca A cloaca ( ), : cloacae ( or ), or vent, is the rear orifice that serves as the only opening for the digestive (rectum), reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles, birds, cartilagin ...

. The act has a variety of names, ranging from the technical (e.g. bowel movement), to the common (like pooping or crapping), to the obscene ('' shitting''), to the euphemistic ("doing number two", "dropping a deuce" or "taking a dump"), to the juvenile ("going poo-poo" or "making doo-doo"). The topic, usually avoided in polite company, forms the basis of scatological humor. Humans expel feces with a frequency varying from a few times daily to a few times weekly. Waves of muscular contraction (known as ''

peristalsis Peristalsis ( , ) is a type of intestinal motility, characterized by symmetry in biology#Radial symmetry, radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an wikt:anterograde, anterograde dir ...

'') in the walls of the colon move fecal matter through the digestive tract towards the

rectum The rectum (: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. Before expulsion through the anus or cloaca, the rectum stores the feces temporarily. The adult ...

. Flatus may also be expulsed. Undigested food may also be expelled within the feces, in a process called ''egestion''. When birds defecate, they also expel

urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...

and urates in the same mass, whereas other animals may also simultaneously

urinate Urination is the release of urine from the bladder through the urethra in placental mammals, or through the cloaca in other vertebrates. It is the urinary system's form of excretion. It is also known medically as micturition, voiding, ure ...

during defecation, but the processes are spatially separated. Defecation may also accompany

childbirth Childbirth, also known as labour, parturition and delivery, is the completion of pregnancy, where one or more Fetus, fetuses exits the Womb, internal environment of the mother via vaginal delivery or caesarean section and becomes a newborn to ...

and

death Death is the end of life; the irreversible cessation of all biological functions that sustain a living organism. Death eventually and inevitably occurs in all organisms. The remains of a former organism normally begin to decompose sh ...

. Babies defecate a unique substance called meconium prior to eating external foods. There are a number of medical conditions associated with defecation, such as

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

and

constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The Human feces, stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the ...

, some of which can be serious. A simpler and more mundane concern is the maintenance of

anal hygiene Anal hygiene refers to practices (anal cleansing) that are performed on the human anus, anus to maintain personal hygiene, usually immediately or shortly after defecation. Anal cleansing may also occur while showering or bathing. Post-defecation ...

, which usually calls for cleaning the area shortly after defecation. The feces expelled can carry diseases, most often through the contamination of food. '' E. coli'' is a particular concern. Before toilet training, human feces are most often collected into a diaper. Thereafter, in many societies people commonly defecate into a

toilet A toilet is a piece of sanitary hardware that collects human waste (urine and feces) and sometimes toilet paper, usually for disposal. Flush toilets use water, while dry or non-flush toilets do not. They can be designed for a sitting p ...

. A Western-style flush toilet requires a sitting position, as compared with a squat toilet. However,

open defecation Open defecation is the human practice of defecating outside ("in the open") rather than into a toilet. People may choose fields, bushes, forests, ditches, streets, canals, or other open spaces for defecation. They do so either because they do ...

, the practice of defecating outside without using a toilet of any kind, is still widespread in some developing countries;WHO and UNICEF (2017
Progress on Drinking Water, Sanitation and Hygiene: 2017 Update and SDG Baselines
Geneva: World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF), 2017 some people in those countries defecate into the ocean. Well-developed countries use

sewage treatment plants Sewage treatment is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water ...

or on-site treatment for blackwater.

Description

Physiology

The rectum ampulla stores fecal waste (also called stool) before it is excreted. As the waste fills the rectum and expands the rectal walls, stretch receptors in the rectal walls stimulate the desire to defecate. This urge to defecate arises from the reflex contraction of rectal muscles, relaxation of the internal anal sphincter, and an initial contraction of the skeletal muscle of the external anal sphincter. If the urge is not acted upon, the material in the rectum is often returned to the colon by reverse peristalsis, where more water is absorbed and the feces are stored until the next mass peristaltic movement of the transverse and descending colon. When the rectum is full, an increase in pressure within the rectum forces apart the walls of the

anal canal The anal canal is the part that connects the rectum to the anus, located below the level of the pelvic diaphragm. It is located within the anal triangle of the perineum, between the right and left ischioanal fossa. As the final functional s ...

, allowing the fecal matter to enter the canal. The rectum shortens as material is forced into the anal canal and peristaltic waves push the feces out of the rectum. The internal and external anal sphincters along with the

puborectalis muscle The levator ani is a broad, thin muscle group, situated on either side of the pelvis. It is formed from three muscle components: the pubococcygeus, the iliococcygeus, and the puborectalis. It is attached to the inner surface of each side of the ...

allow the feces to be passed by muscles pulling the anus up over the exiting feces.

Voluntary and involuntary control

The external anal sphincter is under voluntary control whereas the internal anal sphincter is involuntary. In

infant In common terminology, a baby is the very young offspring of adult human beings, while infant (from the Latin word ''infans'', meaning 'baby' or 'child') is a formal or specialised synonym. The terms may also be used to refer to juveniles of ...

s, the defecation occurs by reflex action without the voluntary control of the external anal sphincter. Defecation is voluntary in adults. Young children learn voluntary control through the process of toilet training. Once trained, loss of control, called

fecal incontinence Fecal incontinence (FI), or in some forms, encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents—including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom ...

, may be caused by physical injury, nerve injury, prior surgeries (such as an episiotomy),

, loss of storage capacity in the

, intense fright,

inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

psychological Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

or neurological factors,

, or

. Sometimes, due to the inability to control one's bowel movement or due to excessive fear, defecation (usually accompanied by urination) occurs involuntarily, soiling a person's undergarments. This may cause significant embarrassment to the person if this occurs in the presence of other people or a public place.

Posture

The positions and modalities of defecation are culture-dependent. Squat toilets are used by the vast majority of the world, including most of Africa, Asia, and the Middle East. The use of sit-down

s in the

Western world The Western world, also known as the West, primarily refers to various nations and state (polity), states in Western Europe, Northern America, and Australasia; with some debate as to whether those in Eastern Europe and Latin America also const ...

is a relatively recent development, beginning in the 19th century with the advent of indoor plumbing.

Disease

Regular bowel movements determine the functionality and the health of the alimentary tracts in human body. Defecation is the most common regular bowel movement which eliminates waste from the human body. The frequency of defecation is hard to identify, which can vary from daily to weekly depending on individual bowel habits, the impact from the environment, and genetics. If defecation is delayed for a prolonged period the fecal matter may harden, resulting in

. If defecation occurs too fast, before excess liquid is absorbed,

may occur. Other associated symptoms can include abdominal bloating, abdominal pain, and abdominal distention. Disorders of the bowel can seriously impact quality of life and daily activities. The causes of functional bowel disorder are multifactorial, and dietary habits such as food intolerance and low fiber diet are considered to be the primary factors.

Constipation

Constipation, also known as defecatory dysfunction, is difficulty experienced when passing stools. It is one of the most notable alimentary disorders that affects different age groups in the population. Common constipation is associated with abdominal distention, pain or bloating. Research has revealed that chronic constipation complied with higher risk of cardiovascular events such as coronary heart disease and ischemic stroke, while associating with an increasing risk of mortality. Besides dietary factors, psychological traumas and 'pelvic floor disorders' can also cause chronic constipation and defecatory disorder respectively. Multiple interventions, including physical activities, 'high-fibre diet', probiotics and drug therapies can be widely and efficiently used to treat constipation and defecatory disorder.

Inflammatory bowel diseases

Inflammatory disease is characterized as long-lasting, chronic inflammation throughout the gastrointestinal tract.

Crohn's disease Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea, fever, abdominal distension, and weight loss. Complications outside of the ...

(CD) and

ulcerative colitis Ulcerative colitis (UC) is one of the two types of inflammatory bowel disease (IBD), with the other type being Crohn's disease. It is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary sympto ...

(UC) are two universal types of inflammatory bowel disease that have been studied over a century. They are closely related to different environmental risk factors, family genetics, and lifestyle choices such as smoking. Crohn's disease has been found to be related to immune disorders particularly. Different levels of cumulative intestinal injuries can cause different complications, such as fistulae, damage of bowel function, symptom recurrence, disability, etc. Patients can be children or adults. Recent research shows that immunodeficiency and monogenic disorders are the causes in young patients with inflammatory bowel diseases. Common symptoms of inflammatory bowel diseases differ by the infection level, but may include severe abdominal pain, diarrhea, fatigue, and unexpected weight loss.

can lead to infection of any part of the digestive tract, including ileum to anus. Internal manifestations include diarrhea, abdomen pain, fever, chronic anaemia, etc. External manifestations include impact on skin, joints, eyes, and liver. Significantly reduced microbiota diversity inside the gastrointestinal tract can also be observed. Ulcerative colitis mainly affects the function of the large bowel, and its incidence rate is three times greater than that of Crohn's disease. In terms of clinical features, over 90 percent of patients exhibit constant diarrhea, rectal bleeding, softer stool, mucus in the stool, tenesmus, and abdominal pain. The symptoms may continue for around 6 weeks or even longer. The inflammatory bowel diseases could be effectively treated by 'pharmacotherapies' to relieve and maintain the symptoms, which showed in 'mucosal healing' and symptoms elimination. However, an optimal therapy for curing both inflammatory diseases are still under research due to the heterogeneity in clinical feature. Although both UC and CD are sharing similar symptoms, the medical treatment of them are distinctively different. Dietary treatment can benefit for curing CD by increase the dietary zinc and fish intake, which is related to mucosal healing of the bowel. Treatments vary from drug treatment to surgery based on the active level of the CD. UC can also be relieved by using immunosuppressive therapy for mild to moderate disease level and application of biological agents for severe cases.

Irritable bowel syndrome

Irritable bowel syndrome is diagnosed as an intestinal disorder with chronic abdominal pain and inconsistency in form of stool, and is a common bowel disease that can be easily diagnosed in modern society. The variation in incident rate can be explained by different diagnostic criteria in different countries, with the 18–34 age group being recognized as the high frequency incident group. The definite cause of irritable bowel syndrome remains a mystery; however, it has been found to relate to multiple factors, such as 'alternation of mood and pressure, sleep disorders, food triggers, changing of dysbiosis and even sexual dysfunction'. One third of irritable bowel syndrome patients has family history with the disease suggesting that genetic predisposition could be a significant cause for irritable bowel syndrome. Patients with irritable bowel syndrome commonly experience abdominal pain, changes to stool form, recurrent abdominal bloating and gas, co-morbid disorders and alternation in bowel habits that caused diarrhea or constipation. However, anxiety and tension can also be detected, although patients with irritable bowel disease seem healthy. Apart from these typical symptoms, rectal bleeding, unexpected weight loss and increased inflammatory markers require further medical examination and investigation. Treatment for irritable bowel disease is multimodal. Dietary intervention and pharmacotherapies can both relieve the symptoms to a certain degree. Avoiding allergic food groups can be beneficial by reducing fermentation in the digestive tract and gas production, hence effectively alleviating abdominal pain and bloating. Drug interventions, such as laxatives, loperamide, and lubiprostone are applied to relieve intense symptoms including diarrhea, abdominal pain and constipation. Psychological treatment, dietary supplements and gut-focused hypnotherapy are recommended for targeting depression, mood disorders and sleep disturbance.

Bowel obstruction

Bowel obstruction is a bowel condition which is a blockage that can be found in both the small intestines and large intestines. Increase of contractions can relieve blockages; however, continuous contractions with decreasing functionality may lead to terminated mobility of the small intestines, which then forms the obstruction. At the same time, the lack of contractility encourages liquid and gas accumulation. and "electrolyte disturbances". Small bowel obstruction can result in severe renal damage and hypovolemia. while evolving into "mucosal ischemia and perforation". Patients with small bowel obstruction were found to experience constipation, strangulation and abdominal pain and vomiting. Surgical intervention is primarily used to cure severe small bowel obstruction condition. Nonoperative therapy included nasogastric tube decompression, water-soluble-contrast medium process or symptomatic management can be applied to treat less severe symptoms According to research, large bowel obstruction is less common than small bowel obstruction, but is still associated with a high mortality rate. Large bowel obstruction, also known as colonic obstruction, includes acute colonic obstruction, where a blockage is formed in the colon. Colonic obstructions frequently occur within the elder population, often accompanied by significant 'comorbidities'. Although colonic malignancy is revealed as the major cause of the colonic obstruction, volvulus has also been founded as a secondary common cause around the world. In addition, lower mobility, unhealthy mentality and restricted living environment are also listed as risk factors. Surgery and colonic stent placements are widely applied for curing colonic obstructions.

Other

Attempting forced expiration of breath against a closed airway (the

Valsalva maneuver The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air, as if blowing up a balloon. Variations of the maneuver can be ...

) is sometimes practiced to induce defecation while on a

. This contraction of expiratory

chest The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...

muscles, diaphragm, abdominal wall muscles, and pelvic diaphragm exerts pressure on the digestive tract.

Ventilation Ventilation may refer to: * Ventilation (physiology), the movement of air between the environment and the lungs via inhalation and exhalation ** Mechanical ventilation, in medicine, using artificial methods to assist breathing *** Respirator, a ma ...

at this point temporarily ceases as the lungs push the chest diaphragm down to exert the pressure.

Cardiac arrest Cardiac arrest (also known as sudden cardiac arrest CA is when the heart suddenly and unexpectedly stops beating. When the heart stops beating, blood cannot properly Circulatory system, circulate around the body and the blood flow to the ...

and other cardiovascular complications can in rare cases occur due to attempting to defecate using the Valsalva maneuver. Valsalva retinopathy is another pathological syndrome associated with the Valsalva maneuver. Thoracic

blood pressure Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...

rises and as a reflex response the amount of blood pumped by the heart decreases. Death has been known to occur in cases where defecation causes the blood pressure to rise enough to cause the rupture of an

aneurysm An aneurysm is an outward :wikt:bulge, bulging, likened to a bubble or balloon, caused by a localized, abnormal, weak spot on a blood vessel wall. Aneurysms may be a result of a hereditary condition or an acquired disease. Aneurysms can also b ...

or to dislodge blood clots (see

thrombosis Thrombosis () is the formation of a Thrombus, blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thrombocytes) and fib ...

). Also, in releasing the Valsalva maneuver blood pressure falls; this, coupled with standing up quickly to leave the toilet, can result in a blackout.

Society and culture

Open defecation

Open defecation Open defecation is the human practice of defecating outside ("in the open") rather than into a toilet. People may choose fields, bushes, forests, ditches, streets, canals, or other open spaces for defecation. They do so either because they do ...

is the human practice of defecating outside (in the open environment) rather than into a

. People may choose fields, bushes, forests, ditches, streets, canals or other open space for defecation. They do so because either they do not have a toilet readily accessible or due to traditional cultural practices. The practice is common where

sanitation Sanitation refers to public health conditions related to clean drinking water and treatment and disposal of human excreta and sewage. Preventing human contact with feces is part of sanitation, as is hand washing with soap. Sanitation systems ...

infrastructure and services are not available. Even if toilets are available, behavior change efforts may still be needed to promote the use of toilets. Open defecation can pollute the environment and cause health problems. High levels of open defecation are linked to high

child mortality Child mortality is the death of children under the age of five. The child mortality rate (also under-five mortality rate) refers to the probability of dying between birth and exactly five years of age expressed per 1,000 live births. It encompa ...

, poor

nutrition Nutrition is the biochemistry, biochemical and physiology, physiological process by which an organism uses food and water to support its life. The intake of these substances provides organisms with nutrients (divided into Macronutrient, macro- ...

poverty Poverty is a state or condition in which an individual lacks the financial resources and essentials for a basic standard of living. Poverty can have diverse Biophysical environmen ...

, and large disparities between rich and poor. Ending open defecation is an indicator being used to measure progress towards the Sustainable Development Goal Number 6.

Extreme poverty Extreme poverty is the most severe type of poverty, defined by the United Nations (UN) as "a condition characterized by severe deprivation of basic human needs, including food, safe drinking water, sanitation facilities, health, shelter, ...

and lack of sanitation are statistically linked. Therefore, eliminating open defecation is thought to be an important part of the effort to eliminate poverty.

Anal cleansing after defecation

The

and

buttocks The buttocks (: buttock) are two rounded portions of the exterior anatomy of most mammals, located on the posterior of the pelvic region. In humans, the buttocks are located between the lower back and the perineum. They are composed of a lay ...

may be cleansed after defecation with

toilet paper Toilet paper (sometimes called toilet/bath/bathroom tissue, or toilet roll) is a tissue paper product primarily used to clean the human anus, anus and surrounding region of Human feces, feces (after defecation), and to clean the external gen ...

, similar paper products, or other absorbent material. In many cultures, such as Hindu and Muslim, water is used for anal cleansing after defecation, either in addition to using toilet paper or exclusively. When water is used for anal cleansing after defecation, toilet paper may be used for drying the area afterwards. Some doctors and people who work in the science and

hygiene Hygiene is a set of practices performed to preserve health. According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refer ...

fields have stated that switching to using a bidet as a form of anal cleansing after defecation is both more hygienic and more environmentally friendly.

Mythology and tradition

Some peoples have culturally significant stories in which defecation plays a role. For example: *In an Alune and Wemale legend from the island of

Seram Seram (formerly spelled Ceram; also Seran or Serang) is the largest and main island of Maluku province of Indonesia, despite Ambon Island's historical importance. It is located just north of the smaller Ambon Island and a few other adjacent i ...

, Maluku Province,

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

, the mythical girl Hainuwele defecates valuable objects. *One of the traditions of Catalonia (

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

) relates to the '' caganer'', a

figurine A figurine (a diminutive form of the word ''figure'') or statuette is a small, three-dimensional sculpture that represents a human, deity or animal, or, in practice, a pair or small group of them. Figurines have been made in many media, with cla ...

depicting the act of defecation which appears in

nativity scene In the Christian tradition, a nativity scene (also known as a manger scene, crib, crèche ( or ), or in Italian ''presepio'' or ''presepe'', or Bethlehem) is the special exhibition, particularly during the Christmastide, Christmas season, of ar ...

s in

Catalonia Catalonia is an autonomous community of Spain, designated as a ''nationalities and regions of Spain, nationality'' by its Statute of Autonomy of Catalonia of 2006, Statute of Autonomy. Most of its territory (except the Val d'Aran) is situate ...

and neighbouring areas with Catalan culture. The exact origin of the ''caganer'' is lost, but the tradition has existed since at least the 18th century.

Psychology

Some aspects of

psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

surround the act of defecation. There is an inherent desire for privacy among humans. Freud stipulated a second stage of development, the Anal Stage, which centers around the release of waste from the bladder and bowels. He categorized two types: '' anal retentive'' and ''anal expulsive''.