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Rotting Food What makes food go bad? It excrete out bile pigments and waste products. This is called Glycogenesis. Studies show that this spice and its antioxidants have potent anti-inflammatory properties 8 , 9. Faeces becomes hard due to long time available for H2O absorption. It is supplied by IX cranial nerve.

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20 amazing facts about the human body

Food enters the mouth where the first stage in the digestive process takes place, with the action of the tongue and the secretion of saliva. The tongue is a fleshy and muscular sensory organ , and the very first sensory information is received via the taste buds in the papillae on its surface.

If the taste is agreeable, the tongue will go into action, manipulating the food in the mouth which stimulates the secretion of saliva from the salivary glands. The liquid quality of the saliva will help in the softening of the food and its enzyme content will start to break down the food whilst it is still in the mouth. The first part of the food to be broken down is the starch of carbohydrates by the enzyme amylase in the saliva. The tongue is attached to the floor of the mouth by a ligamentous band called the frenum [5] and this gives it great mobility for the manipulation of food and speech ; the range of manipulation is optimally controlled by the action of several muscles and limited in its external range by the stretch of the frenum.

The tongue's two sets of muscles, are four intrinsic muscles that originate in the tongue and are involved with its shaping, and four extrinsic muscles originating in bone that are involved with its movement. Taste is a form of chemoreception that takes place in the specialised taste receptors , contained in structures called taste buds in the mouth. Taste buds are mainly on the upper surface dorsum of the tongue. The function of taste perception is vital to help prevent harmful or rotten foods from being consumed.

There are also taste buds on the epiglottis and upper part of the esophagus. The taste buds are innervated by a branch of the facial nerve the chorda tympani , and the glossopharyngeal nerve. Taste messages are sent via these cranial nerves to the brain. The brain can distinguish between the chemical qualities of the food. The five basic tastes are referred to as those of saltiness , sourness , bitterness , sweetness , and umami.

The detection of saltiness and sourness enables the control of salt and acid balance. The detection of bitterness warns of poisons—many of a plant's defences are of poisonous compounds that are bitter.

Sweetness guides to those foods that will supply energy; the initial breakdown of the energy-giving carbohydrates by salivary amylase creates the taste of sweetness since simple sugars are the first result. The taste of umami is thought to signal protein-rich food. Sour tastes are acidic which is often found in bad food. The brain has to decide very quickly whether the food should be eaten or not. It was the findings in , describing the first olfactory receptors that helped to prompt the research into taste.

The olfactory receptors are located on cell surfaces in the nose which bind to chemicals enabling the detection of smells. It is assumed that signals from taste receptors work together with those from the nose, to form an idea of complex food flavours. Teeth are complex structures made of materials specific to them. They are made of a bone-like material called dentin , which is covered by the hardest tissue in the body— enamel.

This results in a much larger surface area for the action of digestive enzymes. The teeth are named after their particular roles in the process of mastication— incisors are used for cutting or biting off pieces of food; canines , are used for tearing, premolars and molars are used for chewing and grinding.

Mastication of the food with the help of saliva and mucus results in the formation of a soft bolus which can then be swallowed to make its way down the upper gastrointestinal tract to the stomach. The epiglottis is a flap of elastic cartilage attached to the entrance of the larynx. It is covered with a mucous membrane and there are taste buds on its lingual surface which faces into the mouth. The epiglottis functions to guard the entrance of the glottis , the opening between the vocal folds.

It is normally pointed upward during breathing with its underside functioning as part of the pharynx, but during swallowing, the epiglottis folds down to a more horizontal position, with its upper side functioning as part of the pharynx. In this manner it prevents food from going into the trachea and instead directs it to the esophagus, which is behind. During swallowing, the backward motion of the tongue forces the epiglottis over the glottis' opening to prevent any food that is being swallowed from entering the larynx which leads to the lungs; the larynx is also pulled upwards to assist this process.

Stimulation of the larynx by ingested matter produces a strong cough reflex in order to protect the lungs. The pharynx is a part of the conducting zone of the respiratory system and also a part of the digestive system. It is the part of the throat immediately behind the nasal cavity at the back of the mouth and above the esophagus and larynx.

The pharynx is made up of three parts. The lower two parts—the oropharynx and the laryngopharynx are involved in the digestive system.

The laryngopharynx connects to the esophagus and it serves as a passageway for both air and food. Air enters the larynx anteriorly but anything swallowed has priority and the passage of air is temporarily blocked. The pharynx is innervated by the pharyngeal plexus of the vagus nerve. The pharynx joins the esophagus at the oesophageal inlet which is located behind the cricoid cartilage. The esophagus , commonly known as the foodpipe or gullet, consists of a muscular tube through which food passes from the pharynx to the stomach.

The esophagus is continuous with the laryngopharynx. It passes through the posterior mediastinum in the thorax and enters the stomach through a hole in the thoracic diaphragm —the esophageal hiatus , at the level of the tenth thoracic vertebra T It is divided into cervical, thoracic and abdominal parts.

The pharynx joins the esophagus at the esophageal inlet which is behind the cricoid cartilage. At rest the esophagus is closed at both ends, by the upper and lower esophageal sphincters. The opening of the upper sphincter is triggered by the swallowing reflex so that food is allowed through. The sphincter also serves to prevent back flow from the esophagus into the pharynx.

The esophagus has a mucous membrane and the epithelium which has a protective function is continuously replaced due to the volume of food that passes inside the esophagus. During swallowing, food passes from the mouth through the pharynx into the esophagus.

The epiglottis folds down to a more horizontal position to direct the food into the esophagus, and away from the trachea. Once in the esophagus, the bolus travels down to the stomach via rhythmic contraction and relaxation of muscles known as peristalsis.

The lower esophageal sphincter is a muscular sphincter surrounding the lower part of the esophagus. The junction between the esophagus and the stomach the gastroesophageal junction is controlled by the lower esophageal sphincter, which remains constricted at all times other than during swallowing and vomiting to prevent the contents of the stomach from entering the esophagus. As the esophagus does not have the same protection from acid as the stomach, any failure of this sphincter can lead to heartburn.

The esophagus has a mucous membrane of epithelium which has a protective function as well as providing a smooth surface for the passage of food. Due to the high volume of food that is passed over time, this membrane is continuously renewed. The diaphragm is an important part of the body's digestive system. The muscular diaphragm separates the thoracic cavity from the abdominal cavity where most of the digestive organs are located.

The suspensory muscle attaches the ascending duodenum to the diaphragm. This muscle is thought to be of help in the digestive system in that its attachment offers a wider angle to the duodenojejunal flexure for the easier passage of digesting material. The diaphragm also attaches to, and anchors the liver at its bare area. The esophagus enters the abdomen through a hole in the diaphragm at the level of T The stomach is a major organ of the gastrointestinal tract and digestive system.

It is a consistently J-shaped organ joined to the esophagus at its upper end and to the duodenum at its lower end. Gastric acid informally gastric juice , produced in the stomach plays a vital role in the digestive process, and mainly contains hydrochloric acid and sodium chloride. A peptide hormone , gastrin , produced by G cells in the gastric glands , stimulates the production of gastric juice which activates the digestive enzymes.

Pepsinogen is a precursor enzyme zymogen produced by the gastric chief cells , and gastric acid activates this to the enzyme pepsin which begins the digestion of proteins. As these two chemicals would damage the stomach wall, mucus is secreted by innumerable gastric glands in the stomach, to provide a slimy protective layer against the damaging effects of the chemicals on the inner layers of the stomach. At the same time that protein is being digested, mechanical churning occurs through the action of peristalsis , waves of muscular contractions that move along the stomach wall.

This allows the mass of food to further mix with the digestive enzymes. Gastric lipase secreted by the chief cells in the fundic glands in the gastric mucosa of the stomach, is an acidic lipase, in contrast with the alkaline pancreatic lipase.

This breaks down fats to some degree though is not as efficient as the pancreatic lipase. The pylorus , the lowest section of the stomach which attaches to the duodenum via the pyloric canal , contains countless glands which secrete digestive enzymes including gastrin.

After an hour or two, a thick semi-liquid called chyme is produced. When the pyloric sphincter , or valve opens, chyme enters the duodenum where it mixes further with digestive enzymes from the pancreas, and then passes through the small intestine, where digestion continues. When the chyme is fully digested, it is absorbed into the blood. Water and minerals are reabsorbed back into the blood in the colon of the large intestine, where the environment is slightly acidic.

Some vitamins, such as biotin and vitamin K produced by bacteria in the gut flora of the colon are also absorbed. The parietal cells in the fundus of the stomach, produce a glycoprotein called intrinsic factor which is essential for the absorption of vitamin B Vitamin B12 cobalamin , is carried to, and through the stomach, bound to a glycoprotein secreted by the salivary glands - transcobalamin I also called haptocorrin , which protects the acid-sensitive vitamin from the acidic stomach contents.

Once in the more neutral duodenum, pancreatic enzymes break down the protective glycoprotein. The freed vitamin B12 then binds to intrinsic factor which is then absorbed by the enterocytes in the ileum. The stomach is a distensible organ and can normally expand to hold about one litre of food.

The stomach of a newborn baby will only be able to expand to retain about 30 ml. The spleen breaks down both red and white blood cells that are spent. This is why it is sometimes known as the 'graveyard of red blood cells'.

A product of this digestion is the pigment bilirubin , which is sent to the liver and secreted in the bile. Another product is iron , which is used in the formation of new blood cells in the bone marrow. The liver is the second largest organ after the skin and is an accessory digestive gland which plays a role in the body's metabolism. The liver has many functions some of which are important to digestion.

The liver can detoxify various metabolites ; synthesise proteins and produce biochemicals needed for digestion. It regulates the storage of glycogen which it can form from glucose glycogenesis. The liver can also synthesise glucose from certain amino acids. Its digestive functions are largely involved with the breaking down of carbohydrates. It also maintains protein metabolism in its synthesis and degradation. In lipid metabolism it synthesises cholesterol. Fats are also produced in the process of lipogenesis.

The liver synthesises the bulk of lipoproteins. The liver is located in the upper right quadrant of the abdomen and below the diaphragm to which it is attached at one part, This is to the right of the stomach and it overlies the gall bladder. The liver produces bile , an important alkaline compound which aids digestion. Bile acts partly as a surfactant which lowers the surface tension between either two liquids or a solid and a liquid and helps to emulsify the fats in the chyme.

Food fat is dispersed by the action of bile into smaller units called micelles. The breaking down into micelles creates a much larger surface area for the pancreatic enzyme, lipase to work on. Lipase digests the triglycerides which are broken down into two fatty acids and a monoglyceride. These are then absorbed by villi on the intestinal wall.

If fats are not absorbed in this way in the small intestine problems can arise later in the large intestine which is not equipped to absorb fats. Bile also helps in the absorption of vitamin K from the diet. Bile is collected and delivered through the common hepatic duct. This duct joins with the cystic duct to connect in a common bile duct with the gallbladder.

Bile is stored in the gallbladder for release when food is discharged into the duodenum and also after a few hours. The gallbladder is a hollow part of the biliary tract that sits just beneath the liver, with the gallbladder body resting in a small depression.

Bile flows from the liver through the bile ducts and into the gall bladder for storage. The bile is released in response to cholecystokinin CCK a peptide hormone released from the duodenum.

The production of CCK by endocrine cells of the duodenum is stimulated by the presence of fat in the duodenum. It is divided into three sections, a fundus, body and neck. The neck tapers and connects to the biliary tract via the cystic duct , which then joins the common hepatic duct to form the common bile duct.

At this junction is a mucosal fold called Hartmann's pouch , where gallstones commonly get stuck. The muscular layer of the body is of smooth muscle tissue that helps the gallbladder contract, so that it can discharge its bile into the bile duct.

The gallbladder needs to store bile in a natural, semi-liquid form at all times. Hydrogen ions secreted from the inner lining of the gallbladder keep the bile acidic enough to prevent hardening.

To dilute the bile, water and electrolytes from the digestion system are added. Also, salts attach themselves to cholesterol molecules in the bile to keep them from crystallising. If there is too much cholesterol or bilirubin in the bile, or if the gallbladder doesn't empty properly the systems can fail.

This is how gallstones form when a small piece of calcium gets coated with either cholesterol or bilirubin and the bile crystallises and forms a gallstone.

The main purpose of the gallbladder is to store and release bile, or gall. Bile is released into the small intestine in order to help in the digestion of fats by breaking down larger molecules into smaller ones. After the fat is absorbed, the bile is also absorbed and transported back to the liver for reuse. The pancreas is a major organ functioning as an accessory digestive gland in the digestive system. It is both an endocrine gland and an exocrine gland.

The endocrine part releases glucagon when the blood sugar is low; glucagon allows stored sugar to be broken down into glucose by the liver in order to re-balance the sugar levels. The pancreas produces and releases important digestive enzymes in the pancreatic juice that it delivers to the duodenum. The pancreas lies below and at the back of the stomach. It connects to the duodenum via the pancreatic duct which it joins near to the bile duct's connection where both the bile and pancreatic juice can act on the chyme that is released from the stomach into the duodenum.

Aqueous pancreatic secretions from pancreatic duct cells contain bicarbonate ions which are alkaline and help with the bile to neutralise the acidic chyme that is churned out by the stomach. The pancreas is also the main source of enzymes for the digestion of fats and proteins. Some of these are released in response to the production of CKK in the duodenum.

The enzymes that digest polysaccharides, by contrast, are primarily produced by the walls of the intestines. The cells are filled with secretory granules containing the precursor digestive enzymes.

The major proteases , the pancreatic enzymes which work on proteins, are trypsinogen and chymotrypsinogen. Elastase is also produced. Smaller amounts of lipase and amylase are secreted. The pancreas also secretes phospholipase A2 , lysophospholipase , and cholesterol esterase. The precursor zymogens , are inactive variants of the enzymes; which avoids the onset of pancreatitis caused by autodegradation. Once released in the intestine, the enzyme enteropeptidase present in the intestinal mucosa activates trypsinogen by cleaving it to form trypsin; further cleavage results in chymotripsin.

The lower gastrointestinal tract GI , includes the small intestine and all of the large intestine. The lower GI starts at the pyloric sphincter of the stomach and finishes at the anus. The small intestine is subdivided into the duodenum , the jejunum and the ileum.

The cecum marks the division between the small and large intestine. The large intestine includes the rectum and anal canal. Partially digested food starts to arrive in the small intestine as semi-liquid chyme , one hour after it is eaten. After two hours the stomach has emptied.

In the small intestine, the pH becomes crucial; it needs to be finely balanced in order to activate digestive enzymes. The chyme is very acidic, with a low pH, having been released from the stomach and needs to be made much more alkaline.

This is achieved in the duodenum by the addition of bile from the gall bladder combined with the bicarbonate secretions from the pancreatic duct and also from secretions of bicarbonate-rich mucus from duodenal glands known as Brunner's glands. The chyme arrives in the intestines having been released from the stomach through the opening of the pyloric sphincter. The resulting alkaline fluid mix neutralises the gastric acid which would damage the lining of the intestine.

The mucus component lubricates the walls of the intestine. When the digested food particles are reduced enough in size and composition, they can be absorbed by the intestinal wall and carried to the bloodstream. The first receptacle for this chyme is the duodenal bulb. From here it passes into the first of the three sections of the small intestine, the duodenum. The next section is the jejunum and the third is the ileum. The duodenum is the first and shortest section of the small intestine.

It is a hollow, jointed C-shaped tube connecting the stomach to the jejunum. It starts at the duodenal bulb and ends at the suspensory muscle of duodenum. The attachment of the suspensory muscle to the diaphragm is thought to help the passage of food by making a wider angle at its attachment.

Most food digestion takes place in the small intestine. Segmentation contractions act to mix and move the chyme more slowly in the small intestine allowing more time for absorption and these continue in the large intestine. In the duodenum, pancreatic lipase is secreted together with a co-enzyme , colipase to further digest the fat content of the chyme. From this breakdown, smaller particles of emulsified fats called chylomicrons are produced.

There are also digestive cells called enterocytes lining the intestines the majority being in the small intestine. They are unusual cells in that they have villi on their surface which in turn have innumerable microvilli on their surface. All these villi make for a greater surface area, not only for the absorption of chyme but also for its further digestion by large numbers of digestive enzymes present on the microvilli.

The chylomicrons are small enough to pass through the enterocyte villi and into their lymph capillaries called lacteals. A milky fluid called chyle , consisting mainly of the emulsified fats of the chylomicrons, results from the absorbed mix with the lymph in the lacteals.

The suspensory muscle marks the end of the duodenum and the division between the upper gastrointestinal tract and the lower GI tract. The digestive tract continues as the jejunum which continues as the ileum. The jejunum, the midsection of the small intestine contains circular folds , flaps of doubled mucosal membrane which partially encircle and sometimes completely encircle the lumen of the intestine. These folds together with villi serve to increase the surface area of the jejunum enabling an increased absorption of digested sugars, amino acids and fatty acids into the bloodstream.

The circular folds also slow the passage of food giving more time for nutrients to be absorbed. The last part of the small intestine is the ileum. This also contains villi and vitamin B12 ; bile acids and any residue nutrients are absorbed here. When the chyme is exhausted of its nutrients the remaining waste material changes into the semi-solids called feces, which pass to the large intestine, where bacteria in the gut flora further break down residual proteins and starches.

The cecum is a pouch marking the division between the small intestine and the large intestine. At this junction there is a sphincter or valve, the ileocecal valve which slows the passage of chyme from the ileum, allowing further digestion. It is also the site of the appendix attachment. In the large intestine , [2] the passage of the digesting food in the colon is a lot slower, taking from 12 to 50 hours until it is removed by defecation.

The colon mainly serves as a site for the fermentation of digestible matter by the gut flora. The time taken varies considerably between individuals. The remaining semi-solid waste is termed feces and is removed by the coordinated contractions of the intestinal walls, termed peristalsis , which propels the excreta forward to reach the rectum and exit via defecation from the anus. The wall has an outer layer of longitudinal muscles, the taeniae coli , and an inner layer of circular muscles.

The circular muscle keeps the material moving forward and also prevents any back flow of waste. Also of help in the action of peristalsis is the basal electrical rhythm that determines the frequency of contractions. Cinnamon is well known for its blood-sugar-lowering properties. Apart from the beneficial effects on insulin resistance, cinnamon can lower blood sugar by several other mechanisms. First, cinnamon has been shown to decrease the amount of glucose that enters your bloodstream after a meal.

It does this by interfering with numerous digestive enzymes, which slows the breakdown of carbohydrates in your digestive tract 14 , Second, a compound in cinnamon can act on cells by mimicking insulin 16 , This greatly improves glucose uptake by your cells, though it acts much slower than insulin itself.

For more information on how you can lower your blood sugar levels, check out 15 easy ways to lower blood sugar levels naturally. Neurodegenerative diseases are characterized by progressive loss of the structure or function of brain cells. Two compounds found in cinnamon appear to inhibit the buildup of a protein called tau in the brain, which is one of the hallmarks of Alzheimer's disease 21 , 22 , In a study in mice with Parkinson's disease, cinnamon helped protect neurons, normalized neurotransmitter levels and improved motor function Overall, the evidence is limited to test-tube and animal studies, which suggest that cinnamon extracts may protect against cancer 25 , 26 , 27 , 28 , It acts by reducing the growth of cancer cells and the formation of blood vessels in tumors and appears to be toxic to cancer cells, causing cell death.

A study in mice with colon cancer revealed that cinnamon is a potent activator of detoxifying enzymes in the colon, protecting against further cancer growth These findings were supported by test-tube experiments, which showed that cinnamon activates protective antioxidant responses in human colon cells Whether cinnamon has any effect in living, breathing humans needs to be confirmed in controlled studies.

For a list of 13 foods that could potentially lower your risk of cancer, you might want to read this article. Cinnamaldehyde, one of the main active components of cinnamon, may help fight various kinds of infection. It can also inhibit the growth of certain bacteria, including Listeria and Salmonella 32 , However, the evidence is limited and so far cinnamon has not been shown to reduce infections elsewhere in the body.

The antimicrobial effects of cinnamon may also help prevent tooth decay and reduce bad breath 34 , Cinnamon extracted from Cassia varieties is thought to help fight against HIV-1, the most common strain of the HIV virus in humans 36 , A laboratory study looking at HIV-infected cells found that cinnamon was the most effective treatment of all 69 medicinal plants studied The Cassia variety contains significant amounts of a compound called coumarin, which is believed to be harmful in large doses.

All cinnamon should have health benefits, but Cassia may cause problems in large doses due to the coumarin content. You may be able to find Ceylon in some health food stores, and there is a good selection on Amazon. At the end of the day, cinnamon is one of the most delicious and healthiest spices on the planet. It can lower blood sugar levels, reduce heart disease risk factors and has a plethora of other impressive health benefits. Just make sure to get Ceylon cinnamon or stick to small doses if you're using the Cassia variety.

Healthline and our partners may receive a portion of the revenues if you make a purchase using a link above. Cinnamon is an incredibly healthy spice that is safe to eat in small amounts. However, eating too much could cause these 6 side effects. Honey and cinnamon can both boost your health, but some people think they have even more powerful benefits when combined. Not all cinnamon is created equal. Ceylon true cinnamon is healthy, while the Cassia variety can be harmful in large amounts.

Cinnamon is a popular spice with many health benefits. This article explores how cinnamon can help lower blood sugar and fight diabetes. Many herbs and natural supplements have been shown to lower blood sugar and protect against diabetes.

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