The Digestive System
MOUTH AND SALIVARY GLANDSThe mouth offers the mechanical (teeth) and initial enzyme breakdown of whole food sources into smaller and simpler complexes. The salivary glands secrete amylase (ptyalin), which is an alkaline digestive enzyme for starch and carbohydrate breakdown. This enzyme hydrolyzes starch and glycogen to maltose.
STOMACH
The stomach is located between your esophagus and duodenum (first portion of the small bowel). It is below the diaphragm and to the right of the spleen. A portion of the stomach lies under the liver. Foods enter the upper portion of the stomach through the cardiac sphincter valve and leave through the pyloric sphincter valve. The wall of the stomach has four layers. The inner lining or mucosa contains simple tubular glands that secrete your gastric juices. Some secrete pepsinogen and others HCL (hydrochloric acid). There are also cells that secrete mucus.
When we see, smell, or imagine food, this triggers the secretion of gastric juices. The actual presence of food stimulates production of the hormone gastrin from the stomach, which in turn releases more gastric juice.
Protein digestion begins in the stomach when the HCL converts pepsinogen to pepsin, which then breaks down complex protein structures into smaller structures called peptones. This is an acid digestive process. If there isn’t any protein in the food consumed, the stomach acts as a temporary holding compartment for carbohydrate and fat digestion. These foods start digesting in the mouth with alkaline digestive juices—amylase (ptyalin), etc. If protein is present, then the stomach acids neutralize these enzymes until these foods move into the duodenum where they are reactivated and added to.
The stomach acts like a time-release capsule, allowing your food time to digest (or be broken down) so the body can actually use it properly. The action of your stomach is through nerve and hormonal control. The stomach can absorb mostly alcohol and water, including tinctured herbs and some fruit and vegetable juices.
Spiritually speaking, your stomach reflects the solar plexus, which is the center of the nerve field that feeds the head (upper), mid, and lower extremities of the body. Weaknesses of the stomach can weaken your whole body, affecting emotions (can foster fear), oxygen demands, consciousness, headaches, and other conditions.
SMALL INTESTINES
The small intestines make up the first part of the bowel structure. The small intestines are smaller in diameter than the colon, but are four to six times as long. There are three distinct sections that make up the small intestines, each having its own job to do.
Duodenum
This first section of the small intestine is approximately 8-11 inches long. Through the common bile duct it receives digestive enzymes, alkalizing sodium of bicarbonate from the pancreas, and alkalizing bile from the gallbladder/ liver. The major portion of this section of the small intestines is primarily digestive and alkalizing. Hormone secretion is also an aspect of the duodenum.
Duodenum Hormones
PEPTIDE
Stimulates the release of pertidase to finish final protein digestion into amino acids
SECRETIN
Stimulates sodium of bicarbonate and bile for alkalization and fat breakdown
CHOLECYSTOKININ
Stimulates pancreatic enzymes and contracts the gallbladder for bile extraction
Duodenum Enzymes
PEPTIDASE
Completes protein breakdown into amino acids
SUCRASE, MALTASE
AND LACTASE
(lactase only to age 3) Change complex sugars into monosaccharides or simple sugars
It is important to understand that the small intestinal walls are made up of circular folds (or villi) called plicae circulares. The mucosa folds itself into these villi or microvilli to increase the absorption surface of the intestines. These appear like ripples or waves that allow the body maximum potential for digesting and absorbing its nutrition.
There are glands called Lieberkuhns at the base of many of the villi (in the duodenum), which secrete digestive hormones and enzymes.
Jejunum
The second portion of the small intestine is approximately 8 feet long. The duodenum and jejunum make up two-fifths of the small intestines. Digestive enzymes from the duodenum are now acting upon most of the food particles. Absorption of vital nutrients is now taking place as the digestive enzymes break down the food particles to their simplest form.
Ileum
The third portion is approximately 15 to 30 feet long and comprises the lower three-fifths of the small intestine. Most of the by-products of digestion now have become amino acids (building blocks), monosaccharides (fuels), fatty acids (oil and fuel), glycerol, vitamins and minerals. These are now being absorbed or mixed with water to continue on their way out into the colon. This liquid mixture now passes into the first part of the large bowel known as the cecum, which is the first section of the ascending portion.
PANCREAS
The pancreas is both an endocrine gland and an exocrine gland and is located in a horizontal position behind the stomach in front of the first and second lumbar vertebrae. The head of the pancreas is attached to the duodenum (small intestines) and the tail of the pancreas reaches to the spleen.
The body of the pancreas has many exocrine glands, which have their own ducts all leading into the main pancreatic duct, which joins the common bile duct. The common bile duct empties into the duodenum (the first portion of the small intestines). All through the exocrine gland tissue are masses of cells called Islets of Langerhans. These are the endocrine systems of the pancreas.
This endocrine portion of the pancreas will be discussed along with the entire endocrine gland system covered later in this chapter. Since we are considering digestion now, we want to examine the exocrine portion of the pancreas, the ducted portion. These glands supply the bulk of the digestive enzymes needed to break down your food. They also supply sodium bicarbonate, which is an alkalizing substance called chyme, which is necessary to alkalize the stomach contents. This chyme is full of HCL (hydrochloric acid) and pepsin. Sodium bicarbonate and bile from the gallbladder join in the duodenum to activate the alkaline digestive enzymes of the pancreas and intestinal wall. If the stomach contents cannot be alkalized, then proper digestion is halted. Your food then ferments and putrefies, causing excessive gas. You then have lost the nutritional value of your foods.
Pancreatic Juice and its Function
SODIUM BICARBONATE
Alkalizer and enzyme activator (neutralizes stomach acid).
TRYPSINOGEN
An enzyme that is converted into trypsin in the duodenum.
CHYMOTRYPSINOGEN
An enzyme that is converted into chymo-trypsin in the duodenum. (Trypsin and chymotrypsin finish protein digestion, converting peptones to peptides. From here, peptides are broken down [from the intestinal wall] by protease into amino acids—the basic building blocks of protein structures.)
AMYLASE
An enzyme which breaks down (hydro-lyzes) starch (maltose) or complex sugars (di- and poly-saccharides) into monosac-charides, or simple sugars.
LIPASE
An enzyme that emulsifies (breaks down) fats into fatty acids and glycerol.
This mixture of enzymes and sodium bicarbonate is called the pancreatic juice. Pancreatic juice has a pH of 8.4 to 8.9, which is alkaline. Pancreatic juice is stimulated by two hormones, se-cretin and cholecystokinin, which are produced by the duodenal mucosa. This pancreatic juice flows through the main pancreatic duct to the common bile duct and then into the duodenum. Pancreatic juice includes sodium bicarbonate (alkalizer) and the enzymes: trypsinogen, chymotrypsinogen, amylase, and lipase.
Your pancreas is one of your vital organs. It is destroyed by acidosis and harmful chemicals. What destroys the liver also destroys the pancreas. Spiritually speaking, your pancreas is tied to your thought processes and how they manifest.
LIVER
Your liver can be compared to a huge chemical factory that supplies a whole city with its functional (metabolic) needs. It has been said that it would require 500 acres of land to build such a factory. Your liver has so many different functions that researchers still haven’t discovered them all. It is enough to say that we should take care of this most precious organ.
The liver is the largest organ in your body and carries on the most functions. It is situated mostly on your right side beneath your diaphragm, level with the bottom of your sternum. The bottom of the liver is concave and covers your stomach, duodenum (the first portion of the small intestines) , hepatic flexure of the colon (upper right turn), right adrenal gland, and the upper portion of the right kidney.
Your liver has four lobes and is covered by a thick, tough, fibrous membrane called the Glisson’s capsule.
All your blood vessels and hepatic ducts enter the liver at the hilus. There are many small intrahepatic bile ducts running through the liver, all leading into the main hepatic duct, which joins the cystic duct from the gallbladder, which then forms the “common bile duct.” This common bile duct then enters the upper portion of your small intestine, called the duodenum, at the papilla of Vater. This is the main digestive area of the body.
The functional parts of your liver are the liver lobules, consisting of the liver cells (hepatocytes), which are permeated by blood capillaries called sinusoids. The sinusoids are lined with the Kupffer cells (macrophages), which are the immune cells of the liver.
Four Basic Tasks
The liver has four basic tasks, out of which arise a multitude of functions. These tasks are:
STORAGE AND DISTRIBUTION — The liver stores various amino acids obtained from digestion, then reconstructs them for essential body proteins. The liver converts excess glucose into glycogen (stored fat), then converts the stored glycogen back to glucose when the body needs extra fuel. The liver also stores and distributes various vitamins, including Vitamin A, D, E, and K (your fat-soluble vitamins). Your liver also stores various minerals, including iron and copper.
CONVERSIONS, SYNTHESIS, BIOLOGICAL TRANSMUTATIONS — The liver stores glycogen, and when your blood glucose levels drop, it will convert this stored fat (glycogen) into glucose again. If our glycogen reserves are depleted, it will convert other fats and even stored amino acids into glucose. This shows you that the number one priority of your body is the need for fuels for energy (glucose/fructose).
Liver Function
AMINO ACID METABOLISM
Synthesis of non-essential amino acids.
Will convert amino acids into glucose (energy) if needed. (It is not recommended to allow your body to get this far in its energy needs.)
Forms urea from excess amino acids and ammonia.
CARBOHYDRATE METABOLISM
Converts monosaccharides (other than glucose) into glucose.
Excessive glucose is converted and stored as glycogen, and vice versa.
FAT METABOLISM
Cholesterol is synthesized for new cell growth and steroid production.
Lipo proteins, which are transporters of fat, are synthesized.
Fatty acids are converted to acetyl groups or ketones, which are used for energy.
Bile pigments, including bilirubin, are formed from the hemoglobin of old red blood cells.
Bile is synthesized for fat emulsifying and alkalizing stomach contents.
The liver converts ammonia from excessive protein consumption into urea, which is then excreted by the kidneys. Your liver synthesizes Vitamin K and other various clotting factors, including prothrombin and fibrinogen. It synthesizes non-essential amino acids for growth and repair functions.
Cholesterol is synthesized for use in cell membrane walls, steroid production, and for anti-inflammatory purposes. Various minerals and elements are transmuted into other elements. An example of this is silica, which is transmuted into calcium. The liver also synthesizes albumin and globulin, which are carrier molecules.
SECRETION — Your liver produces and secretes approximately 1 liter of bile per day. Bile is a fat emulsifier and alkalizing agent.
DETOXIFICATION — The liver’s immune (Kupffer) cells digest bacteria, viruses and other pathogens within the blood from the digestive tract. A healthy liver can metabolize hormones, chemical drugs, and other chemicals to a certain degree. However, our daily ingestion of these substances is more than most livers can cope with. The liver also produces enzymes to help with the above detoxification process.
You can see from the above functions and processes what your liver does, and how important it is to keep it healthy! Acidosis, alcohol, toxic chemicals, drugs, etc., are all extremely harmful to your liver. Almost all drugs, especially coal tar products like aspirin, severely destroy its tissues. It’s your liver—send it love and be good to it!
Your liver is also tied to your mind in ways not yet understood by most people. When the liver is inflamed and impaired in its function, so is your mind. This can create low self-esteem and anger. Remember that your body develops and functions according to how you treat it. Be good to yourself.
GALLBLADDER
Your gallbladder is a pear-shaped sac that is located on the underside of the right lobe of your liver. Your gallbladder is a “holding tank” for bile, which is produced in the liver. As bile is stored in the gallbladder, the body removes water from it, making it concentrated.
As bile is needed for digestive purposes, it moves through a 3-inch duct called the cystic duct into the hepatic duct, which then forms the common bile duct. The hepatic duct then empties into the duodenum (the first portion of the small intestine).
Bile is used as an alkalizer, anti-inflammatory, and emulsifier of fats. It works with pancreatic lipase to break down large fat molecules. Bile contains bilirubin, biliverdin, cholesterol, organic and inorganic substances and salts, lecithin, mucin, etc.
Cholecystokinin (pancreozymin) is a hormone from the intestinal wall (of the duodenum) that causes the gallbladder to contract, releasing bile. Cholecystokinin (pancreozymin) is triggered by fats entering the small bowel.
In Summary
The tissues of the alimentary canal, which is called the digestive tract, are formed from several layers of cells. The first layer is called the mucous membrane; it lines all passages and cavities of the body that have contact with oxygen. This mucous membrane consists of epithelial cells, also referred to as the mucosa, which secretes moisture or mucus to aid in the protection and function of the respective organ. We also have the sub-mucosa or basement membrane. Then the connective and the smooth muscle tissues. Most of the mucus of the mucosa comes from the Brunner’s glands, which are located in the sub-mucosa.
We consume food and drink for the very purpose of obtaining fuels, as well as for building and repairing materials. Basically, most elements and compounds are used as energy sources for the body. All foods and drinks must first be broken down from their gross unusable forms into their simplest or nutritional substances so the body can absorb them and use them. Cell membrane walls have microscopic pores so that only the simplest of elements can enter. If not, large particles may enter and cause cellular damage.
Physically, however, most by-products of digestion, if properly broken down into their simplest form, can now be absorbed through the villi into the capillary (blood) bed. The blood now acts as a transporter, carrying the nutrients, building blocks and fuels to the liver, then to the heart, and finally releasing them into the general system for its needs. By-products of digestion include amino acids, monosaccharides (simple sugars), fatty acids, glycerol, vitamins and minerals, etc.
