ConstipationConstipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement. Complications from constipation may include hemorrhoids, anal fissure or fecal impaction. The normal frequency of bowel movements in adults is between three per day and three per week. Babies often have three to four bowel movements per day while young children typically have two to three per day.
Gut microbiotaGut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis.
Lactose intoleranceLactose intolerance is caused by a lessened ability or inability to digest lactose, a sugar found in dairy products. Humans vary in the amount of lactose they can tolerate before symptoms develop. Symptoms may include abdominal pain, bloating, diarrhea, flatulence, and nausea. These symptoms typically start thirty minutes to two hours after eating or drinking something containing lactose, with the severity typically depending on the amount consumed. Lactose intolerance does not cause damage to the gastrointestinal tract.
LaxativeLaxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubricant, and saline laxatives are used to evacuate the colon for rectal and bowel examinations, and may be supplemented by enemas under certain circumstances. Sufficiently high doses of laxatives may cause diarrhea. Some laxatives combine more than one active ingredient, and may be administered orally or rectally.
FlatulenceFlatulence, in humans, is the expulsion of gas from the intestines via the anus, commonly referred to as farting, tooting, or passing gas. "Flatus" is the medical word for gas generated in the stomach or bowels. A proportion of intestinal gas may be swallowed environmental air, and hence flatus is not entirely generated in the stomach or bowels. The scientific study of this area of medicine is termed flatology. Flatus is brought to the rectum and pressurized by muscles in the intestines.
Abdominal painAbdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues. Common causes of pain in the abdomen include gastroenteritis and irritable bowel syndrome. About 15% of people have a more serious underlying condition such as appendicitis, leaking or ruptured abdominal aortic aneurysm, diverticulitis, or ectopic pregnancy. In a third of cases the exact cause is unclear.
DiarrheaDiarrhea, also spelled diarrhoea or diarrhœa, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour. This can progress to decreased urination, loss of skin color, a fast heart rate, and a decrease in responsiveness as it becomes more severe. Loose but non-watery stools in babies who are exclusively breastfed, however, are normal.
Coeliac diseaseCoeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barley. Classic symptoms include gastrointestinal problems such as chronic diarrhoea, abdominal distention, malabsorption, loss of appetite, and among children failure to grow normally. This often begins between six months and two years of age.
Enteric nervous systemThe enteric nervous system (ENS) or intrinsic nervous system is one of the main divisions of the autonomic nervous system (ANS) and consists of a mesh-like system of neurons that governs the function of the gastrointestinal tract. It is capable of acting independently of the sympathetic and parasympathetic nervous systems, although it may be influenced by them. The ENS is nicknamed the "second brain". It is derived from neural crest cells.
Non-celiac gluten sensitivityNon-celiac gluten sensitivity (NCGS) or gluten sensitivity is "a clinical entity induced by the ingestion of gluten leading to intestinal and/or extraintestinal symptoms that improve once the gluten-containing foodstuff is removed from the diet, and celiac disease and wheat allergy have been excluded". NCGS is included in the spectrum of gluten-related disorders. The definition and diagnostic criteria of non-celiac gluten sensitivity were debated and established by three consensus conferences.
