Encyclopedia of Homeopathy

188 •SERIOUS AILMENTSDIGESTIVE SYSTEMThe digestive system basically consists of a long tube thatstarts at the mouth and ends at the anus. The aim of thesystem is to break food down for absorption into the body.Associated digestive organs, such as the liver, processnutrients into substances that can be used for the productionof energy and for the building and repair of body tissues,cells, and the constituents of blood—metabolic processesthat take digestion a stage further.Digestion & metabolismThe human body needs energy to function.That energy comes from food, but only afterit has been processed into substances that canbe assimilated by various parts of the body.Some nutrients, such as minerals, can beabsorbed directly along the way down thedigestive tract, but substances such asproteins have to be broken down intosmaller molecules.Food processingDigestion starts in the mouth, where salivacontaining a digestive enzyme called amylaselubricates food as it is chewed. In thestomach proteins and fats are broken downin an acidic environment, and salt, water, andalcohol are absorbed. Beyond the stomach (inthe duodenum), acidity is neutralized beforefood is treated by secretions from associateddigestive organs—the liver, gallbladder, andpancreas. Bile from the liver and gallbladderemulsifies fats, and pancreatic enzymes breakdown proteins, starch, and fats.In mouth, teeth crush foodinto small pieces, which arerolled by tongue into ballready for swallowingSalivary glands secretenzyme into mouth tolubricate food and startdigestive breakdownFood is rhythmicallysqueezed downesophagusTHE DIGESTIVE TRACT From wherefood enters the body at the mouthto where waste products areexpelled at the anus, thedigestive tract extends overa distance of up to 26 ft (8 m).Food can take anything from13 to 20 hours to completeits journey through the system.Coordinated by the hypothalamusin the brain, the digestive systemincludes associated digestive organssuch as the liver, gallbladder,and pancreas.Using nutrientsThe liver is, in effect, the chemical factoryof the body. Among many importantmetabolic functions, it stores glucose,vitamins, and minerals produced by foodprocessing but not immediately usable by thebody, and facilitates the breakdown of fats,which is vital for the conversion of food intoenergy. As well as digestive enzymes, thepancreas produces insulin (a hormone), andglycogen (a starch), both of which regulatesugar levels. Diabetes is the result ofdiminished insulin action. In the smallintestine, the breakdown of food is completed.Nutrients are absorbed into the blood, carriedto cells, and used in the release of energy.Undigested food is expelled from the anus.Digestive ailments such as irritable bowelsyndrome or ulcerative colitis are believedto result from, among other factors, anunsuitable diet or chemical imbalancesin the metabolic process.Liver is keyorgan controllingmetabolismSolid wastepasses intorectum beforebeing expelledfrom anusIn stomach, foodis broken down byhydrochloric acidand pepsin (anenzyme)Hormones in pancreasstimulate release ofenzymes to breakdown food and controlabsorption of nutrientsDigested foodconstituents areabsorbed throughwalls of smallintestine into bloodand lymph vesselsWater is absorbedfrom undigestedfood in colon