What Is It?

The small intestine is the largest part of the gastrointestinal tract and is composed of the duodenum which is about one foot long, the jejunum (5-8 feet long), and the ileum (16-20 feet long).

The duodenum is the major portion of the small intestine where enzyme secretion takes place. The named enzymes end with the letters "ase". The small intestine secretes sucrase (breaks sucrose into glucose and fructose); maltase (breaks maltose into glucose); and lactase (breaks lactose into glucose and galactose, lactase is missing in a good percentage of people). It also secretes petidase to split peptides (from protein) into amino acids, and lipase to break down fat into glycerol and fatty acids.

The duodenum receives bile from the liver and gallbladder, to decrease the surface tension between the large fat globules and water, and break them into smaller globules that can be acted upon by lipase, amylase, trypsin, chymotrypsin and sodium bicarbonate are received from the pancreas upon hormonal signals from pancreozymin and other hormones (produced in the small intestine) and neural signals from the vagus nerve.

Epithelial cells in the small intestine secrete over ½ gallon of a neutral fluid daily to supply a watery substance to mix with the chyme and provide a substance to aid in electrolyte and vitamin absorption through the villi.

Brunner’s glands in the duodenum secrete mucus in response to secretin, vagal stimulation, and direct stimulation of food in the small intestine. This mucus protects the duodenal wall from the digestive juices. Goblet cells in the mucosa also produce mucus. In general the duodenum isn’t as well protected with mucus as is the stomach and is more prone to ulcers. A deficiency of pancreatic juices to neutralize the acid chyme from the stomach, or stress causing sympathetic inhibition of enzyme secretion can lead to duodenal ulcer formation.

Approximately ½ the carbohydrate digestion is performed by amylase from the pancreas, 40% from the saliva, 10% from intestinal amylase. Ninety five percent of the fat digestion is performed by pancreatic lipase and 5% from intestinal and stomach lipase.

Almost 90% of our daily fluid intake is absorbed in the small intestine. The small intestine is covered with villi and microvilli. They increase the surface area of the intestinal wall exposed to chyme by 60,000%. The increased surface area makes the small intestine very efficient in absorption. Capillaries in the villi absorb amino acids, glucose, fructose, and galactose while lacteals absorb fatty acid and glycerol to travel through the lymphatic vessels.

As chyme enters the small intestine, the acidity of it causes secretion of the hormone secretin, which signals the pancreas to secrete alkaline juices to neutralize the chyme. The chyme also initiates a type of small intestine contraction known as segmentation which helps to mix and chop the chyme and propel it along. These contractions occur about once every 5 seconds in the duodenum but only half as fast in the ileum. Peristaltic waves also occur and aid in chyme propulsion. It takes about 2-3 minutes for the chyme to advance 1 inch, and all together food can remain in the small intestine between 3-10 hours normally. Eating and stomach distention both can increase peristalsis in the small intestine. Harmful irritants reaching the small intestine can initiate what is called a peristaltic rush which can empty the entire small intestine into the colon within a few minutes. Food you are allergic to can also do this and lead to diarrhea due to the lack of time for fluid absorption.

The small intestine is the area in the digestive tract where almost all of the nutrients from food are absorbed into the blood stream. Of course, to make it through the intestinal wall, the size of the food particles needs to be very small, down to the level of molecules. If the food has not been properly broken down by the time it gets to this point, it will not get through and cause irritation along the intestinal wall. If this process continues, the irritation will progress to inflammation and symptoms similar to those seen in Crohn’s Disease can occur. These include chronic diarrhea or bouts of diarrhea and constipation, bleeding from the intestinal tract and break down of the intestinal wall. Nutrient deficiencies will also occur because the body will not be able to retrieve them from partially digested food.

A relatively new condition, called Leaky Gut Syndrome, is coming to the forefront as more and more people report symptoms like increased food allergies, increased autoimmune diseases, fatigue, poor digestion, cramping, and diarrhea. The name Leaky Gut Syndrome pretty much explains what is going on in this disease. The intestines are allowing larger particles into the blood stream, which can not be utilized by the cells and are seen as foreign invaders by the immune system. Every meal a new group of foreign molecules ends up in the blood stream, making the immune system "fight" them off. In a short amount of time the immune system becomes exhausted and the constant signal to be on "alert" wears out the adrenal glands. Stress hormones become depleted and a chronic state of fatigue ensues. In fact, some research suggests that many cases of chronic fatigue syndrome and fibromyalgia may have their root cause in Leaky Gut Syndrome.

Good Bacteria

Another danger to intestinal health is the loss of naturally occurring bacteria that are responsible for extracting some nutrients and for producing the majority of vitamin K circulating in the body. Vitamin K is a necessary part of the clotting mechanism and recent research shows it plays an important role in preventing osteoporosis. This imbalance in the ecosystem within also gives yeast cells free reign to grow unchecked. Antibiotics are the number one reason why "good" intestinal bacteria die off. For this reason, it is important to replace them by taking probiotic supplements like acidophilus and bifidus bacteria during and after a course of antibiotics, and to eat cultured foods like yogurt, kefir, and miso, or blue, brie and camembert cheeses. (Please note: the yogurt must have live cultures, which will be listed on the label.) Fructooligosaccharides, also known as FOS, is a fancy name for certain nutrients, which have been found to nourish the "good bacteria" in the digestive tract. One of the highest sources of FOS is tomatoes. FOS is found in the supplement Lact-Enz ®.

Contact Reflex Analysis Findings

The following reflexes are commonly found to be active when there is dysfunction with the small intestine:

• Pus Reflex - Chronic Fatigue Syndrome Sub-Reflex
• Intestinal Flora Pus Sub-Reflex
• Liver-Metal Overlad Pus Sub-Reflex
• Parasite Pus Sub-Reflex
• Right Master Allergy Bile Duct Sub-Reflex
• Right Master Allergy Gallbladder Sub-Reflex
• Right Master Allergy Liver Sub-Reflex
• Gut Sub Reflex
• Metabolic Duodenum-Small Intestine Sub-Reflex
• Metabolic Liver Sub-Reflex
• Metabolic Stomach Sub-Reflex
• Metabolic Gallbladder Sub-Reflex
• Metabolic Pancreas Sub-Reflex
• Metabolic Toxic Bowel-Large Intestine Reflex Sub-Reflex
• Virus Reflex
• Yeast Reflex

These reflexes should be tested and treated with the proper supplementation. A liver/gallbladder flush and intestinal detoxification program may also be recommended.

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