Introduction and getting food into the digestive tract





In this issue, we begin a series on the digestive system. Effectively, this system is a continuous tube from the mouth to the anus -- something you probably don't want to think about the next time you kiss someone. Over the course of the next half dozen or so newsletters, I'm going to walk you through the digestive system -- from the tip of your tongue to the outer edge of your rectum. We're going to cover the anatomy and physiology of everything from your teeth to your bowel, plus the organs of digestion including the liver, gallbladder, and pancreas. All of this will help you understand the nature of diseases of the digestive tract (everything from hiatal hernia to acid reflux, from peptic ulcers to irritable bowel syndrome) and how to treat them naturally by working with your body, not against it.

Along the way, I'm going to be challenging a number of medical assumptions. How can that be? Aren't anatomy and physiology pretty much cut and dried? And the answer is: "Not necessarily." As it turns out, the body responds differently according to what you eat, how you eat it, and how that food is prepared. Virtually, all physiological assumptions used by the medical community are based on observation of people eating the typical high speed modern diet. Change the diet, and you change the physiology.



And in fact, these differences are critical. It has been said that we dig our graves one forkful at a time. By understanding exactly how our body processes what we eat and how what we eat affects those processes, we can change our health outcomes. Effectively, we can delay the digging of our graves for years. And maybe even more importantly, we can enjoy those years with a much higher level of health and vitality. I'm sorry, but people who tell me they are perfectly healthy because they are successfully "managing" their acid reflux and Crohn's disease with medications are not actually healthy. They are merely suppressing the symptoms of unhealth…temporarily.



Obviously, this is a huge topic and can't be covered in one newsletter. Effectively, I'm going to break the discussion into several pieces, including:



*Getting food into the digestive tract -- the mouth and esophagus

*The organs that support digestion -- the liver, gallbladder, and pancreas

*Absorbing nutrients -- the small intestine

*Processing and eliminating the waste -- the colon



Digestive system overview



Before we launch into the focus of today's newsletter, the mouth and esophagus, let's take a quick overview of the entire system.

The digestive system is also known as the gastrointestinal (GI) tract and the alimentary canal and covers everything from the digestive tract itself to the organs that support it. It is a continuous tube-like structure that develops outpouchings, which in turn evolve into those aforementioned attached digestive organs such as the pancreas, liver, and gallbladder. The entire system is about 40 feet in length from the mouth to the anus and is designed to transport food and water, modify it, and make it suitable for absorption and excretion. There are storage sites, excretion sites, and detoxifying sites along the way. And, according to the medical community, it has six primary functions.



1. Ingesting food.

2. Preparing food for digestion by physically grinding it and breaking it down into small pieces and unwinding

proteins so they can be separated into their component amino acids.

3. Actually breaking the food into molecular pieces that your body can use as nourishment.

4. Transporting the food during its various stages of breakdown along the digestive tract in a

measured, "manageable" flow.

5. Absorbing the nutrients into the body. Absorption is the movement of broken-down nutrients across the

digestive tract wall and into the bloodstream for use by the cells of the body. Only water and alcohol are

absorbed through the mucosa of the stomach – and only in special circumstances such as severe

dehydration. All the rest of absorption happens in the small intestine.

6. Eliminating the unused waste products of digestion and absorption from the body.

1. Digested waste products go to the kidneys

2. Undigested waste products pass out through the colon and rectum.

3. Ingested material that might otherwise be toxic is rendered harmless, primarily by the liver, and excreted

from the body.



But that said, I now have my first disagreement with the medical community. I submit to you that the above list is incomplete, and that these omissions are not unimportant. For example, medicine has no understanding of the role your digestive system plays in maintaining an optimal environment for beneficial bacteria and why that's essential. Therefore, they both allow and, in fact, encourage by their treatments many diseases to manifest that should never appear -- and have no idea how to treat them when they do. And that's just one example that we'll explore in more detail later on. So, from a holistic point of view, the digestive system, in addition to the functions listed above, also performs the following functions:



* It is the first line of defense in the body's immune system. It both identifies and eliminates viruses and

unhealthy bacteria ingested with our food and water.

* It plays a key role in helping remove, not just food waste from the body, but also metabolic waste, heavy

metals, and drug residues.

* It also serves as a drain for toxic substances absorbed through the skin and lungs.

* And, of course, as mentioned above, it is designed to serve as a hospitable breeding ground for trillions of

beneficial bacteria that do everything from aiding in digestion, waste elimination, and immune function. In fact,

as much of 60% of your immune function comes from beneficial bacteria living in your intestinal tract.



Carnivore, omnivore, frugivore?

There is one other piece of overview information we need to cover. The medical community bases its assumptions concerning the human digestive system on the "fact" that it is essentially designed as an omnivore system. (Only people at tailgate parties and gladiator games actually believe that we are pure carnivores.) But, as I discussed in detail in Lessons from the Miracle Doctors, this is simply not supported by the evidence at hand. And once again, this distinction is not subtle…and not insignificant. Yes, the human body has an amazing ability to adapt to any diet we throw at it -- but not without consequences. And, in fact, many of the diseases we face today are the direct result of not understanding what our systems are designed to handle and the consequences we face as a result.



How could the medical community be so wrong on this issue? Actually, it's very simple, and it's the same old problem. As usual, the medical community views the body as separate pieces, not as an integrated whole. It looks at things in isolation. In this particular case it looks at the diet of the 99% of population that passes through their doors in need of their care, and those people eat everything from cotton candy to slabs of grilled beef -- an omnivore diet. Given this context, for medical anatomists, the digestive system is undeniably designed for an omnivore diet. However, it takes only a slightly more holistic viewpoint to make a casual comparison of the structures of the human digestive system (teeth, stomach, and intestines) to other animals living in the wild to see how unsupportable that point of view is. And in fact, we will cover those differences in detail as we move through the digestive system and discuss each relevant organ.



And with all that said, let's now begin our trip through the digestive system.



Getting food into the digestive tract -- the mouth and esophagus



Let's begin our exploration of the digestive system by examining the structures that play a key role in getting the food into the stomach. And since this is not an actual anatomy course, but a series of newsletters about how anatomy and physiology relate to alternative health, we will focus our discussion on the specific parts of the system relevant to our discussion and brush lightly over the rest.



Mouth



The mouth is the portal to the digestive system. Food enters the body through the mouth, where it is cut and ground by the teeth and moistened by saliva for ease in swallowing and to start the digestive process. The tongue assists in moving food around during chewing and swallowing and also contains the taste buds.



Teeth



Most medical texts suggest that our teeth are designed to eat all kinds of food from meat to fruit, thus proving that man is an omnivore. But as I mentioned earlier, the facts do not bear this out. Here is a human skull and teeth.

Notice how all of the teeth are nearly the same height. Our canines project only a small amount, and our molars are broad-topped.



Compare this to the teeth of a carnivore such as lion.

The first thing you notice about carnivores is that their teeth are nothing like those found in humans. They have huge canines for striking and seizing prey, pointed incisors for removing meat from bones, and molars and premolars with cusps for shredding muscle fiber. In carnivores, the teeth of the upper jaw slide past the outside of the lower jaw so that prey is caught in a vice-like grip. In general, carnivores don't chew much; mostly, they just tear chunks off and swallow them whole. All in all, nothing like human teeth.



But the claim in medical texts is that we are omnivores, not carnivores. How does that claim stand up? Well, first of all, no animal is really adapted to eat all things, but if any animal comes close, it would be the bear. Typical foods consumed by bears include ants, bees, seeds, roots, nuts, berries, insect larvae such as grubs, and even flowers. Some meat, of course, is eaten by bears, including rodents, fish, deer, pigs, and lambs. Grizzlies and Alaskan brown bears are well-known salmon eaters. Polar bears feed almost exclusively on seals, but then, what vegetation is there for them to eat in the frozen wastes of the Arctic? And, of course, anyone who has read Winnie the Pooh knows that many bears love honey. So, other than the ants, grubs, and rodents, the bear diet sounds a lot like the typical Western diet. So let's take a look at the bear's teeth.

Notice, the bear has the sharp canines of the carnivore and the pronounced incisors of the herbivore. They also have molars that are both pointed and broad topped. That's not even close to the human set of teeth pictured earlier.



So, does that mean we are restricted to a diet of fruits and nuts? Not at all! In fact, the frugivores we most closely resemble, the wild chimpanzees, periodically eat live insects and raw meat. Notice the picture of a chimp's teeth.

Other than the long canines, they are virtually identical to human teeth.



Among the great apes (the gorilla, the orangutan, the bonobo, and the chimpanzee) and ourselves, only humans and chimpanzees hunt and eat meat on a frequent basis. Gorillas have never been observed hunting or feeding on any animals other than invertebrates such as termites and ants. Nevertheless, chimpanzees are largely fruit eaters, and meat comprises only about 3 percent of their diet -- far less than is found in the typical Western diet.



Bottom line: at least as defined by our teeth, we do not qualify as carnivores or omnivores. So, at least as judged by our teeth, meat should comprise no more than 3% of our diet. But teeth do not comprise the end of the issues. Later on, we'll compare stomachs and intestinal tracts to see if we match up any better there.



Tongue



The tongue is the largest muscle in the mouth. It functions in chewing, swallowing, and forming words. The extrinsic muscles of the tongue (those muscles that originate outside the tongue itself) attach to the skull and neck, and they move from side to side and in and out. The intrinsic muscles attach to the tongue itself, and they alter the tongue's shape (for swallowing and speech). The most interesting parts of the tongue in terms of our discussion are the papillae, the bumps on the tongue that contain the taste buds.

Taste buds are composed of groups of about 40 column shaped epithelial cells bundled together along their long axes. Taste cells within a bud are arranged such that their tips form a small taste pore. Minute, hair-like threads called microvilli extend through this pore from the actual taste cells. The microvilli of the taste cells bear the actual taste receptors, and it appears that most taste buds contain cells that bear receptors for two or three of the basic tastes.



There are four tastes we normally associate with taste buds: sweet, salty, sour, and bitter. However, research has identified a fifth taste our buds can identify. The fifth taste is umami, the taste of monosodium glutamate (no kidding), and has recently been recognized as a unique taste, as it cannot be elicited by any combination of the other four taste types. Glutamate is present in a variety of protein-rich foods, and particularly abundant in aged cheese.



Unless artificially disrupted, our sense of taste will guide us to the foods necessary for our survival. And, in fact, our taste preferences change according to our body's needs. Just ask the husband of any pregnant woman. Or more scientifically:



* Removal of the adrenal glands without replacement of mineralocorticoids leads rapidly to death due to

massive loss of sodium from the body. Adrenalectomized animals (animals whose adrenal glands have been

surgically removed) show a clear preference for salty water over pure water, and if provided with salt water,

can actually survive.

* If the parathyroid glands are removed, animals lose calcium and cannot maintain blood calcium levels

appropriately due to deficiency in parathyroid hormone. Following parathyroidectomy (removal of the

parathyroid glands), animals choose drinking water that contains calcium chloride over pure water or water

containing equivalent concentrations of sodium chloride.

* Injection of excessive doses of insulin results in hypoglycemia (low blood sugar). Following such treatment,

animals will preferentially pick out and consume the sweetest among a group of foods.



Now, there are three tastes I want to focus on.



Sweet

The sweet taste was designed to cause us to desire natural carbohydrates essential for our survival. As we discussed above, our teeth match those of the frugivores, largely fruit eaters. However, technology has allowed food manufacturers to exploit our desire for sweet things -- to our detriment. For the most part, concentrated sugars, other than honey, are not naturally available for us to consume. Table Sugar is a manufactured creation, as is maple syrup, agave syrup, not to mention high fructose corn syrup, glucose, dextrose and all of the other concentrated sweeteners added to our food. If living in nature, our desire for sweets would lead us to low concentrations of Sugar bound to fiber, not 32 oz Big Gulp sodas containing almost a cup of concentrated sugar. The bottom line is that these concentrated sweeteners feed an addiction because, based on evolution, our taste buds never expected to find concentrated sweeteners -- only natural foods, with a far less concentrated character. And to make matters even worse, the more concentrated sweeteners we eat, the more we crave.



Umami

A similar situation exists with umami, also known as "savory." In nature, this taste is never concentrated, and exists only in very small amounts in selected foods. Concentrating it as a food additive, confuses the system and allows us to consume glutamate in far higher levels than our bodies were ever designed to handle -- with highly disruptive health effects for sensitive people.



Bitter

And then there's bitter! Bitterness is the most sensitive of the five tastes. It has been suggested that the evolutionary purpose of "bitter" is to warn us against ingesting toxic substances, many of which have a bitter character. Unfortunately, this association between bitter and unhealthy is not entirely true, and our current culinary desire to avoid bitter tastes causes us to miss the health benefits associated with many bitters. Common bitter foods and beverages include coffee, unsweetened chocolate, bitter melon, beer, bitters, olives, citrus peel. But how many people eat them in their unadulterated form any more. Bitters are almost always masked by added sugar. In any case, whereas at one time people regularly consumed bitters as part of their diet, we pretty much completely avoid them now. When's the last time you saw a fast food or soda pop based on bitter?



This has major health consequences for your liver. The body has a number of built-in feedback loops, a number of which we'll cover as we move through the digestive system, such as the triggers that both stimulate and shut off the production of stomach acid. But the simple fact is that the taste of bitter in the mouth is stimulating to the liver. There is a direct feedback loop from the tongue to the liver. Every time you taste something bitter, your liver gets a positive jolt that stimulates it to put out more essential bio-chemicals and expel accumulated toxic waste. If you never taste any bitter, your liver tends to become sluggish over time and retain toxic build-up. This is one of the key reasons that the Liver Tincture and Blood Support formulas I use during detoxing have such a pronounced bitter taste. In fact, all of the great liver herbs, milk thistle, dandelion root, and Picrorhiza Kurrooa are decidedly bitter.

Nose/Smell



Although not usually considered, anatomically, as part of the digestive system, the nose really does qualify. After all, up to 75% of what we perceive as taste is due to smell. And the mere smell of certain foods can stimulate hunger and the production of digestive juices. Thus, simple nasal maintenance, such as daily nasal cleansing, is an important part of good intestinal health -- not to mention the fact that it washes out vast quantities of bacteria and viruses, thus preventing them from entering the digestive tract. Incidentally, the primary role of the uvula, the fleshy piece that hangs from the back of the throat, is to detect food that passes over it, and rise up during swallowing to close off the nose from the food so it can't back up into the nose.



Salivary glands



There are three pairs of salivary glands that secrete saliva, the first of the digestive juices to contact the food in the mouth. They are:

1 The parotid glands, which are located high up in each cheek, just below the ears. Incidentally,

these are the glands that gets infected and swell up when you have the mumps. 2. The submandibular glands, which are located in the floor of the mouth just below the parotid

glands. 3. And the sublingual glands, which are located on the floor of the mouth, upfront.



Saliva performs several key functions. It moistens the mucous membrane, moistens food for easy swallowing, lubricates the esophagus for swallowing, washes the mouth, kills bacteria, dilutes poisonous substances, and contains enzymes that begin the digestion process. Your body produces from 1-1.5 liters of saliva per day (about a quart). More than 99% of that saliva is water, and almost all of it is reabsorbed in the digestive tract. The tiny bit of saliva that is not water contains about 0.05% enzymes:



* Lysozyme kills bacteria in the mouth. Incidentally, your mouth is remarkably dirty and infested

with bacteria -- some good, but most not so much. It is really true that the mouth of a dog that

drinks from the toilet is cleaner than yours. And if you must be bitten, better to be bitten by a dog

than a person. *Lingual lipase breaks triglycerides down into far healthier and more easily digested fatty acids

and monoglycerides. * And then there's salivary amylase



Salivary amylase begins the breakdown of carbohydrates



Your digestive system is remarkably adaptable; after all, it can handle pepperoni pizza, beer, and Ding Dongs. But there are consequences if you abuse it. There are two forms of abuse. First, there's eating a diet high in cooked and processed food that has destroyed all of the enzymes naturally present in the food. In this particular case, we're talking about amylase. All natural carbohydrates contain the amylase needed to digest them. In fact, the amylase found in wheat and other grains will actually work in the stomach at high acid pH levels of 3 to 4. If natural amylase is present, it will handle a great deal of the digestive process required to break down the carbohydrates you eat. Second, you need to chew your food thoroughly. If you chew your food well enough, it slows down the entire eating process, which spreads out the glycemic response. It also allows the amylase in the saliva to effectively start breaking down the carbohydrates, which takes a huge burden off your pancreas. And it allows time for your stomach to signal your brain that you're full (it normally takes twenty minutes for your brain to catch up with your stomach), so you end up eating less.



So, how much do you need to chew your food? There's an old saying: "You should drink your solids and chew your liquids." What that means is that you should chew the dry food you eat until it turns to liquid in your mouth (about forty chews per mouthful), and that you should swish liquids back and forth in your mouth (chew them as it were) an equal number of times. This helps mix enzymes into the food or liquid and begins the digestive process.



The more you chew, the more effective these enzymes are.



And if you don't do these things, how much does the body have to compensate? Amylase levels in the saliva of people eating the typical western cooked/processed diet are as much as 40 times higher than that found in people eating a more natural diet!



Note: During dehydration, the brain signals the mouth to stop the flow of saliva to impel us to drink more water and to conserve fluids.



Swallowing (deglutition)



Once you start chewing your food and mixing it with saliva, it picks up a technical name; the wad of chewed food is called a bolus. During the voluntary stage of swallowing, the tongue moves the bolus of food upward and backward. Once the bolus reaches the back of the throat, all actions become involuntary -- they happen outside of your conscious control. During the first of these involuntary phases, the muscles move the food down and back into the esophagus. And finally, the food is actively moved through the esophagus to the stomach. By actively, I'm referring to the fact that movement through the esophagus is the result of series of active, coordinated movements by constrictor muscles lining the esophagus -- not the result of gravity. Specifically, longitudinal muscles pull the esophagus up and relax lower portions so that the circular bands of muscle lining the esophagus can constrict and move the bolus down into the stomach. In fact, although it is not advisable, you can easily swallow when hanging upside down.

As we discussed in our series on breathing, aspiration (entry of food or water) into the lungs and nasopharynx is prevented in a series of involuntary actions.



* The uvula and soft palate move upward to close off the nasopharynx.

* The larynx is pulled forward and upward under the protection of the tongue.

* The epiglottis moves back and down to close the opening of the trachea and airway.

* Food slides over the epiglottis into the esophagus.

* Vocal cords close to further block the airway.

* Breathing ceases for about 2 seconds while this process takes place, then resumes.

Esophagus ("carries food")



Although there are a number of things that can go wrong with the esophagus, they are mostly medical and fall outside the scope of our discussion. For our purposes, the only function of the esophagus is to carry food from the mouth to the stomach. No digestion or absorption of nutrients takes place in the esophagus. Liquids pass through quickly -- in about a second. A food bolus, on the other hand will take about five to nine seconds to make its way through the esophagus.



In fact, there is little to interest us from an alternative health point of view until we reach the lower esophageal sphincter, which is located at the end of the esophagus just above the diaphragm. The sphincter is not actually an anatomical structure. It's just an area at the end of the esophagus that is capable of constricting to effectively separate the stomach from the esophagus. When functioning properly, it allows food to enter the stomach while at the same time preventing stomach acids and bile from refluxing back into the esophagus.



From a medical point of view, there are a number of things that can go wrong with the lower esophageal sphincter, such as achalasia (inability to relax), which prevents food from entering the stomach. But for the purposes of our discussion, two conditions stand out: GERD and hiatal hernia. These conditions used to be handled surgically, but with rather poor results. Antacids provided temporary relief, but as we will learn when we discuss the stomach, actually aggravated the problems. Now, new drugs called proton pump inhibitors are the treatment of choice. They work by cutting the ability of the body to produce stomach acid and are more effective, from a medical point of view, than either surgery or antacids.





GERD



GERD (Gastro esophageal reflux disease) is also known as acid reflux disease. It is a condition in which the sphincter fails to prevent acid from backing up into the esophagus. This causes inflammation, scarring, and can lead to esophageal cancer. We will talk more about GERD when we talk about acid production in the stomach, which is the primary contributing factor in this disease. We will also discuss why Prilosec, Prevacid, and Nexium may not be the best answers to this problem. One other note on acid reflux at this time is that hiatal hernia is often a contributing factor.





Hiatal hernia



Hiatal hernia is a condition in which part of the stomach moves above the diaphragm, into the chest. They are much more common than generally recognized and can produce a wide variety of symptoms that make diagnosis difficult. Hiatal hernias can manifest as severe chest pains that mimic a heart attack, pressure in the chest, or severe stomach pain. And most notably, as mentioned above, a hital hernia can significantly aggravate acid reflux as it pushes the esophageal sphincter out of position, thereby seriously compromising its ability to prevent stomach acid from moving into the esophagus.

There are very few medical options for treating a hiatal hernia. As I mentioned earlier, surgical intervention is only marginally effective. The common medical approach today is to reduce the amount of acid the stomach produces with proton pump inhibitor drugs. But the use of these drugs is even more questionable for a hiatal hernia than for standard GERD as it does nothing at all to alleviate the underlying condition -- the fact that part of your stomach is now up in your chest cavity. It merely helps control one symptom.

Fortunately, there are alternatives.



* Self massage

* Chiropractic adjustment

* Then, once you've corrected the initial hiatal hernia you might want to do some yoga exercises

to strengthen your diaphragm so that your stomach won't slip back up through the opening

again. For example: * Kapalabhati

* Uddyiana Bandha



Conclusion



~The need for enzymatic digestion

~Why proton pump inhibitor drugs create at least as many problems as they resolve

~How stomach acid is produced in your body and how to use that feedback loop to your advantage

~Why antacids create more acid than they get rid of

~Peptic ulcers and how to get eliminate them

~The proper way to eat to control appetite

~The types of food your stomach is anatomically designed to handle

~The feedback loop that drains your body of enzymes

~And much more





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By: Jon Barron

As we work our way down the digestive tract, we encounter two major "outpouchings" -- the pancreas and the liver. Like the mouth and the stomach, these outpouchings represent evolutionary adaptations of the GI tract from its original straight line tube construction as found in more primitive animals such as worms. In today's newsletter, we are going to focus on the pancreas, both its anatomy and physiology. The pancreas actually plays two major roles in the body. It both produces hormones and digestive juices that dump into the duodenum, and it produces Sugar and growth regulating biochemicals that empty directly into the bloodstream. In this newsletter, we will focus on the digestive functions (and the problems associated with those functions) and save the Sugar and growth regulating functions for a later discussion when we explore the body's endocrine system. We will also explore how abuse of this commonly ignored organ (through poor diet, inadequate supplementation, and lack of regular cleansing) can lead to serious -- even fatal -- health problems.

There is one important note/perspective before we begin. The word pancreas actually means something. Translated from the original Greek, it reads as "all flesh" (pan -- all, kreas -- flesh), which refers to its ability to digest virtually all flesh (protein based tissue), including itself.

Physical facts about the pancreas

Most organs in the abdomen, such as the intestines, stomach, and liver are located in the peritoneal cavity. Just like we saw with the heart, which was located in the pericardial cavity, the peritoneal cavity is lined with a sac like membrane called the parietal peritoneum. Also, as with the heart, the organs inside the peritoneal cavity are covered with a visceral membrane.

The pancreas, however, does not fit this description. Like the kidneys, the rectum, and most of the duodenum, the pancreas is what is called a retroperitoneal organ. That means it lies within the peritoneal cavity but outside (behind) the visceral peritoneum or membrane. From a natural health perspective, as we explore the anatomy and physiology of the pancreas, this distinction has little meaning. On the other hand, to the surgeon, it matters a great deal.

Physically, the pancreas is located in the middle to upper abdominal cavity, towards the back or posterior. It is about 12 inches long and tapers from right to left. (Remember, as with our discussion of the heart, anatomically speaking, left and right are referenced from behind the body so they are actually reversed in most diagrams that view the body from the front.) The thick part, the head, comprises almost 50% of the mass of the pancreas and lies to the right, nestled in the curve of the duodenum. This location, as we will learn in a bit, is key to the functioning of the pancreas. As for the body of the pancreas, it moves up and to the left, tapering into what is known as the tail of the pancreas, which terminates at the junction of the spleen.

This locates the pancreas in terms of its head and tail. As for the front surface of the pancreas, it rests mostly against the back (posterior) wall of the stomach. The rest of it nestles against the first portion of the duodenum. This can be important in the case of duodenal ulcers that actually penetrate the duodenum -- as the ulcer will now begin to spread to the pancreas, leading to severe, often fatal, pancreatitis.

As might be suspected for such an important organ, the pancreas is richly supplied with arteries and veins. It is served by branches from the hepatic artery, the gastroduodenal artery, the pancreaticoduodenal artery, the superior mesenteric artery, and the splenic artery.

Pancreatic duct system

The pancreas shares a duct system with the liver in what is known as the biliary tree. We will discuss the complete tree in more detail when we talk about the liver in our next issue of the newsletter. When it comes to natural health, a complete understanding of the biliary tree and how to keeps its functioning optimized is essential to maintaining optimal health. For now, though, we will focus on that part of the tree that resides in the pancreas.

The pancreas is served by a major pancreatic duct (the duct of Wirsung) that runs down the middle of the pancreas and empties into the duodenum at the head of the pancreas through a valve called the ampulla of Vater. (Some people have a secondary duct (the duct of Santorini) that splits off from the main duct and empties into the duodenum just above the ampulla of Vater -- but this duct is usually non-functional.) It is important to note that the main duct joins the common bile duct (through which the liver and gallbladder empty) at the point it enters the duodenum. This is important as stones from the gallbladder can find their way down into the pancreatic duct, blocking it at the ampulla of Vater and leading to pancreatitis.

Secretory cells that release pancreatic juice are arranged in acini (clusters of cells that resemble many-lobed "berries") around small ducts that feed into progressively larger ducts and ultimately into the main duct -- virtually identical to the tracheal-bronchi tree we saw in the lungs.

Pancreatic function

Endocrine and exocrine functions coexist in the pancreas. By definition, endocrine organs secrete hormones directly into the bloodstream, whereas exocrine organs secrete hormones directly into the cavity (lumen) of another organ. The pancreas does both. The exocrine pancreas comprises 99% of pancreatic tissue. It secretes digestive juices into the duct system that carry them on into the cavity of the duodenum. The endocrine pancreas, on the other hand, secretes hormones (insulin, glucagon, and >somatostatin) directly into the bloodstream. Simple math tells us that if 99% of pancreatic tissue serves the exocrine function of the pancreas, only 1% of pancreatic tissue is available for its endocrine function. Oh, but how important that 1% is. It is so important (and complex) that we will save our discussion of it for a separate newsletter when we explore the body's endocrine system. Once again, our focus on this issue is on the digestive system; therefore, our focus in this newsletter is on the exocrine function of the pancreas.

Finally, it should be noted that the major stimulation of the pancreas is primarily parasympathetic (originating in the brain stem), through the vagus nerve, and promotes secretion of digestive juices. Parasympathetic stimulation to the pancreas occurs in response to the digestive processes of the stomach. Food in the stomach stimulates the secretion of all pancreatic enzymes. And in fact, we covered the pancreatic triggering mechanisms in great detail in our exploration of the stomach.

Conversely, inhibition of pancreatic secretion of digestive juices is controlled by triggers and nerves outside of the central nervous system -- the sympathetic nervous system. Specifically, when acid chyme enters the duodenum, along with partially digested fats, proteins, and carbohydrates, enteroendocrine cells in the duodenum and small intestine release cholecystokinin (CCK) and secretin. Secretin decreases gastric secretion and CCK inhibits gastric emptying. These two enzymes circulate into the bloodstream. In addition, they stimulate further secretion of pancreatic enzymes and sodium bicarbonate into the small intestine, thus further raising the pH in the duodenum.

Pancreatic digestion

As we've discussed in previous newsletters, the primary processes of digestion occur in the stomach, and the primary processes of absorption occur in the small intestine. However, both these functions depend heavily on the digestive juices secreted by the pancreas -- specifically, the exocrine secretions of the pancreas that dump into the duodenum. The exocrine pancreas has the following components and functions.

Pancreatic juice

The pancreas produces 1,000-1,500 mL (1-1.5 qts) of digestive juices per day. These juices consist primarily of water, NaCl (salt), and NaHCO3 (sodium bicarbonate). The purpose of the sodium bicarbonate is to neutralize the high acidity of the chyme (food plus stomach acid) raising it to an alkaline pH of 7.1-8.2. This both stops the action of gastric pepsins and stomach acid and prepares chyme for the process of nutrient absorption, which takes place in the small intestine.

Pancreatic enzymes

In addition to containing sodium bicarbonate to neutralize the action of the digestive juices, pancreatic juice also contains a number of digestive enzymes (optimized to function in an alkaline environment) that help finish off the digestive process started in the stomach. (Obviously, and we will talk more about this later), the more complete the digestive process that took place in the stomach, the fewer digestive enzymes will be needed from the pancreas to finish the process. And in fact, the more complete will be the process of absorption in the small intestine.) These pancreatic enzymes include:

• Amylase digests the remaining complex carbohydrates into sugars -- mostly complex. Complex sugars are then further broken down into their individual component sugars in the small intestine:
  
  
  
  • Maltose (glucose + glucose) is acted on by maltase and broken down into two molecules of glucose.
  
  
  • Sucrose (glucose + fructose) is acted on by sucrase and broken down into glucose and fructose.
  
  
  • Lactose (glucose + galactose) is acted on by lactase and broken down into glucose and galactose.
  
  
  
  


• Trypsin, chymotrypsin, and elastase all digest proteins.


• Lipase digests triglycerides into fatty acids and monoglycerides.
  
  
  
  

Almost all pancreatic enzymes are secreted in an inactive form to prevent autodigestion. (Remember, pancreas literally means "eats all flesh.") Inactive forms of enzymes end in "gen", e.g. trypsinogen. If the pancreatic enzymes were in the active form inside the pancreas, they would literally digest the pancreas itself. This is, of course, identical to what we saw in the stomach, in which the mucosal cells of the stomach lining release pepsinogen, pepsin's precursor -- which is converted into pepsin only after the pepsinogen has made its way out of the chief cells and into the stomach itself, where it is converted in the presence of stomach acid. Since the wall of the stomach is coated with mucous, the pepsin can only digest your meal and not your stomach. This would not be the case, of course, if the pepsinogen converted to pepsin while still in the stomach lining. And the same is true for the pancreatic enzymes, which only convert to their active form once they are fully clear of the pancreas itself. Incidentally, it is enterokinase (produced in the small intestine) that activates the pancreatic enzymes once they are in the safe confines of the small intestine. In the small intestine, the mucosal lining protects the tissue of the small intestine from autodigestion -- as in the stomach.

In severe pancreatitis, however, activated enzymes may travel back into the pancreas and digest it. We will talk more about pancreatitis in a little bit, but for now, consider alcohol. Regular consumption of alcohol inflames the pancreas. When the inflammation is severe, the smaller ducts of the pancreas are squeezed shut. Thus, the pancreatic enzymes do not readily flow through the duct system, but rather are released into the blood of the pancreas, where they become active and start digesting the pancreas itself. (Blockage of the biliary tree is also a major problem and can cause enzymes to back up and autodigest pancreatic tissue. We will explore this in more detail in a couple of newsletters when we focus on the biliary tree.)

It should be noted that the pancreas has self-defense mechanisms that can help prevent auto digestion -- at least in minor cases of back up. For example, the acinar cells (mentioned earlier) contain a trypsin inhibitor that inactivates any active trypsin accidentally released into the pancreatic tissues.

The role of the pancreas in digestion

We've assumed a basic understanding of what the purpose of digestion is in all of our discussions of the digestive process so far, but never really defined it in specific detail. Now would be a good time. The purpose of digestion -- with the contribution of the pancreas -- is to take the generally complex molecules of the food you eat and break them down into simple molecules and reassemble those molecules into necessary compounds. That's it, in a nutshell. For example, by eating foods with proteins containing the essential amino acids, the body can break those proteins down into their component amino acids through the efforts of the stomach and the pancreas, then send those amino acids to the liver, which then reassembles them to produce the full complement of non-essential amino acids the body needs. Essential amino acids are those which the body cannot assemble in the liver. Non-essential amino acids are those which can be manufactured in the liver -- as long as the right mix of essential amino acids is present in the diet. Essentially the same process is involved in digesting carbohydrates and fats -- breaking down complex molecules of great variety into smaller molecules of limited variety.

That's the simple description. If we take it one level deeper, it becomes even more interesting.

As it turns out, the body has evolved to favor molecules with similar structures. This presents the body with two major advantages. First, it makes the digestive process easier, since the body has only a limited number of end products it is trying to produce. But even more importantly, it makes reassembling molecules into more complex structures that much simpler since they all have fundamental similarities no matter what their function. For example, the four ring cyclopentanophenanthrene structure is common to all of the steroid hormones including: cholesterol, estradiol, testosterone, and cortisol. The only differences between these compounds are one or two groups attached to the outside of the common ring structure. I discussed this in detail in Lessons from the Miracle Doctors when exploring the make-up of hormones in the body. They all look remarkably similar because they share the same basic ring structure, but with tiny variations. Look at how remarkably similar the testosterone and estrone molecules are -- and yet how remarkably different they are in function. One makes men; the other makes women.

The bottom line is that because they are remarkably similar, it is that much easier for the body to assemble the basic building blocks after digestion into whatever is needed: testosterone, DHEA, estrogen, cortisol, cholesterol. You name it. Thus, the body can easily replace any particular missing compound by modifying the creation process of a similar compound. And in fact, we see this all the time in the body. For example, if you remove the ovaries to drop estrogen production to combat breast cancer, it only provides temporary relief. Estrogen levels will miraculously start to rise again eventually. How? The adrenals take over and start producing estrogen from the almost identical cortisol building block. Miraculous!

Incidentally, that's why doctors now prefer tamoxifen to removing ovaries. Instead of eliminating the body's ability to produce estrogen (which always shifts over to another organ), tamoxifen works to block estrogen receptor sites so that vulnerable tissue cannot "take up" any estrogen circulating in the bloodstream. Of course, this can also be done using natural health resources without the side effects and cost, but that's a topic for another newsletter.

What can go wrong with your pancreas?

Problems with the pancreas usually come down to two things -- pancreatitis and pancreatic cancer.

Pancreatitis

Quite simply, pancreatitis refers to inflammation of the pancreas; usually marked by abdominal pain. The primary causes are identified in the medical community as alcohol, Gallstones (by virtue of the shared biliary tree), infection, and certain medications such as diuretics. It is estimated that some 50,000 to 80,000 cases of acute pancreatitis occur in the United States each year. But that's just the tip of the iceberg. Acute pancreatitis only documents those cases accompanied by abdominal pain or threat of death. But what about asymptomatic non-acute pancreatitis? How prevalent is that?

Unfortunately, doctors and hospitals do not document the incidence of non-acute pancreatitis since they offer no treatment for it. But researchers such as Edmund Howell in his book Enzyme Nutrition DE CLAREd that virtually 100% of all Americans have an enlarged pancreas by the time they are 40! Is this possible? In fact, yes! There are strong indications that a major factor in chronic non-acute pancreatitis is the stress put on the pancreas through a diet high in cooked and processed foods -- a diet deficient in natural or supplemented enzymes.

Research done on rats and chickens that were fed cooked foods revealed that the pancreas enlarged to handle the extra burden of the enzyme-deficient diet. In other words, the pancreas will enlarge over time when called upon to compensate for a diet high in enzyme deficient foods. Ruminant animals such as cattle, goats, deer, and sheep get along with a pancreas about a third as large as the human pancreas because of their raw food diet. However, when these animals are fed heat-processed, enzyme-free food, their pancreas enlarges up to three times the normal size than when fed on a raw plant diet. Grossman, M. Greengard, H, Ivy, A. American Journal of Physiology. 141:38-41, 1944. Make no mistake; long-term, non-acute pancreatitis is a condition that affects virtually every person living on a modern diet -- given enough time. And just because doctors ignore it because it appears to be asymptomatic (at least in the short term), does not mean that you should be so cavalier about it. Over time, it has a profound impact on your health.

Pancreatic cancer

Just like pancreatitis, the incidence of pancreatic cancer is rising dramatically in the developed world. At one time virtually unknown, there are now some 25,000 cases a year in just the US -- with a 95% mortality rate. In fact, the overall 5-year survival rate from pancreatic cancer is only about 2%. The first symptoms usually noticed are caused by the pancreatic tumor blocking the bile duct and causing a bile reflux into the bloodstream, resulting in jaundice as the first indicator. Even worse, though, are cancers of the tail and body of the pancreas, which produce no symptoms until they are far advanced. In the whole history of pancreatic cancer (millions of cases), there are only 5 known survivors of body and tail pancreatic cancer -- patients whose cancer was discovered early on, by pure accident.

Surgical treatment of pancreatic cancer involves removing the pancreas, duodenum, the bile ducts, and half the stomach and reconnecting the remaining organs (the Whipple procedure). This is one of the biggest surgeries known, requiring from 6-14 hours to complete. It has a five year survival rate of just 2%, and in fact, almost half of all patients die on the operating table. Treatment of pancreatic cancer is especially difficult because the location of the pancreas means that tumors tend to spread rapidly to highly innervated (rich in nerves) regions of the back and spine.

The causes of the rising incidence are unknown within the "medical community," although one link that has definitely been established is smoking. The bottom line is that if you get pancreatic cancer, there is very little the medical community can do for you. When the medical community accuses the natural health community of diverting people away from effective treatments for cancer, there is no way they could be looking in a mirror if they are talking about pancreatic cancer. All the medical community can offer in the case of pancreatic cancer is great pain and suffering -- and at huge cost. On the other hand, within the natural health community, we can once again make some educated assumptions that may allow you to better your odds of never getting pancreatic cancer in the first place.

Using natural health to optimize your pancreas

The steps for taking care of your pancreas are fairly simple.

Basic concepts of pancreatic health

• Chronic pancreatitis: Long-term inflammation of the pancreas (pancreatitis) has been linked to cancer of the pancreas. In fact, long-term, non-acute inflammation of the pancreas may be the single leading cause of pancreatic cancer. Reducing inflammation of the pancreas, both acute and non-acute is fundamental to pancreatic health.


• Diabetes: Diabetes is not only a symptom of pancreatic cancer, but long-standing Type 1 diabetes significantly increases the risk of pancreatic cancer.


• Obesity: Obesity also significantly increases the risk of pancreatic cancer.


• Alcohol: Consume alcohol only in moderation as even small quantities of alcohol inflame the pancreas, not to mention the liver.


• And quit smoking: Statistically, smoking doubles the risk of pancreatic cancer. It has been estimated that as many as one in four cases of pancreatic cancer are the direct result of smoking cigarettes. Conversely, the risk of pancreatic cancer drops close to normal in people who quit smoking.
  
  

Diet

Diets high in meats, cholesterol, fried foods, and nitrosamines increase the risk of both pancreatic cancer and pancreatitis, while diets high in raw fruits and vegetables reduce risk. The bottom line is that a Mediterranean diet is pancreas friendly.

Supplemental digestive enzymes

Unless you're living on an all raw food diet, you need to be supplementing with digestive enzymes. Insufficient live digestive enzymes in the diet force the pancreas to overwork and overstress resulting in long-term, non-acute enlargement of the pancreas. Using digestive enzymes with every meal is one of the simplest things you can do to improve the health of your pancreas.

Kidney, gallbladder, liver flushes

We will cover this issue in more detail when we focus on the liver and biliary tree. However, there can be no question but that regularly softening and flushing of gallstones that can block both the gallbladder and the pancreatic ducts is fundamental to preventing pancreatitis and pancreatic cancer.

Endocrine function

All of the above steps will help with maintaining the health of the endocrine pancreas, but there is more that you can do to support that 1% of pancreatic function. However, we need to save that for our discussion of the body's endocrine system, when we will have time to explore that function in detail. In the meantime, for a heads up on additional steps you can take, check out Diabetes: the Echo Effect.

In our next issue of the newsletter, we will continue our exploration of the digestive system as we take on the liver -- one of the most fascinating and important organs in the body.




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Alternative Health Newsletter!

And now we reach the heart of the intestinal tract. Everything so far has been preparation for this discussion. Digestion, or breaking food down into
smaller bits, is certainly important -- crucial even -- but to what purpose? The purpose, quite simply, is to get the nutrition inherent in the food you
ate ready so that it can be absorbed into your body where it can be used by each and every single cell to survive and carry on its individual function.
When it comes to the intestinal tract, the key is absorption. It's not what you eat or digest that matters; it's what you absorb. And when it comes to
absorption, the small intestine is the portal for virtually all nutrients that enter into the bloodstream.

Note: much of this discussion is easy to understand, but the core of it, the actual act of absorption is quite technical and involves some chemistry. As
always, I will only deal with as much chemistry as is absolutely necessary -- and will present it in such a way as to make it comprehensible.

Digestion -- setting up absorption

Before we can get to absorption, we have to cover the final stages of digestion that take place in the small intestine. In fact, you get a combination of
mechanical and chemical digestion and some absorption in the small intestine. Early in the intestine it is mostly digestion, very little absorption.
However, the further on you move down the digestive tract, the more the ratio swings in favor of absorption. Effectively, the entire small bowel (duodenum,
jejunum, and ileum) is devoted to these two processes: digestion and absorption. Digestion itself is divided into mechanical and chemical phases.

Mechanical digestion

Mechanical digestion, as we alluded to in our exploration of the anatomy of the small intestine, is the
result of two very different, but complementary actions:

• 
  Segmentation contractions chop, mix, and roll the chyme (the mixture of food and digestive juices).
  


• 
  Peristalsis slowly propels the chyme forward toward the large intestine.
  

Segmentation represents localized activity in the small intestine, whereas peristalsis represents the more global movement that takes place throughout the
entire intestinal tract.

In segmentation, circular muscles constrict and divide the small bowel into segments -- each about 3-4 inches long. A muscle then contracts between the two
other muscles and subdivides the segment. This is repeated many times per minute so that the chyme is moved back and forth in the same area of the segment.
Localized contractions crush and mix food within that segment alone. This action mixes the chyme with intestinal juices and prolongs its contact with the
absorptive surface of the small intestine. Relaxation allows the segments to coalesce, thus allowing chyme to move on down the intestinal tract -- pushed
by peristalsis.

Peristaltic contractions represent a global movement that is designed to move chyme through the entire length of the small intestine and ultimately
complement the mechanical process of segmentation that holds chyme in individual segments of the intestinal tract. Peristalsis is completely under the
control of the autonomic nervous system and is coordinated by the myenteric plexi (plexuses). The myenteric plexus, also known as Auerbach's plexus, is a
network of nerves between the circular and longitudinal layers of the muscles surrounding the intestinal tract.

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Segmentation in a sheep's small intestine

It should be noted that peristaltic activity is weak (as opposed to segmentation), which means that food stays in the small bowel for a relatively long
time (4-6 hours). And it should also be noted that peristalsis can be fairly easily slowed or even stopped by outside factors. Culprits include
appendicitis, surgery, medication, and even very large meals. On the other hand, there are certain things that can increase peristalsis such as laxatives
and certain kinds of illness or toxicity. As anyone who has experienced food poisoning or stomach flu would know, peristalsis is quite capable of shooting
food through the intestinal tract when required. In simple terms, the body responds to toxins in the intestinal tract by adhering to the old bromide, "The
solution to pollution is dilution." In effect, the body pours fluid into the intestines and increases peristalsis to eject and weaken toxins in cases such
as bacterial contamination. In extreme situations such as presented by cholera, victims may actually die of dehydration from massive diarrhea. Note: in
cases of massive diarrhea, you cannot drink enough water to compensate for the loss of fluids. Without the use of massive IV's, you will die of
dehydration.

It should also be noted that in the period between meals, when the small intestine is for the most part empty, peristaltic contractions continue throughout
the entire small intestine. Think of it as housekeeping activity, designed to sweep the small bowel clear of debris. This movement is the cause of
"growling" that can be heard when people have not eaten for awhile.

Chemical digestion

By the time chyme reaches the small bowel, it is a mix of partially digested carbohydrates, lipids, and proteins -- not yet ready for absorption. Digestion
must be completed in the small intestine, because the colon will not absorb nutrients to any significant degree. As I mentioned earlier, the ratio of
digestion to absorption changes dramatically as the chyme moves through the small intestine and is exposed to ever more chemical digestion. Specifically,
digestion for each type of nutrient proceeds as follows.

Proteins

Proteins are denatured (unwound) by acid and broken down by pepsin in the stomach. For the most part, they arrive as polypeptides (short-chain amino acids)
in the small intestine. The extent of breakdown into polypeptides is dependent on several factors such as:

• 
  The amount of proteases that arrive undamaged with the food to significantly break down proteins before being neutralized by the release of stomach
  acid (about 45 minutes after food enters the stomach) -- or the use of supplemental digestive enzymes to make up the difference.
  


• 
  The ability of the stomach to produce sufficient stomach acid to denature the protein. If the protein is not unwound from its tight ball-like structure
  into a long chain, pepsin won't be able to work on it.
  


• 
  Sufficient pepsin production to chop up the protein into its smaller component chunks.
  


• 
  Any use of antacids or proton pump inhibitor drugs, of course, totally compromise the ability of the body to break down proteins in the stomach since
  they suppress the stomach acid required to unwind the protein.
  

Any breakdown not accomplished in the stomach must now be compensated for in the small intestine -- in addition to the small intestine's role in breaking
down short-chain amino acids into even smaller molecules capable of being absorbed into the bloodstream. In either case, after proteins leave the stomach,
breakdown continues in the small bowel by activated pancreatic enzymes, including trypsin, chymotrypsin, and elastase (which breaks down elastin fibers).
All three are necessary because they each act at different places in the amino acid sequences.

In addition, brush border cells of the small bowel excrete more peptidases -- enzymes such as aminopeptidase and dipeptidase -- that complete the splitting
of the amino acids into ever smaller components. Ultimately, this creates molecules small enough to transport across the brush border cells and into the
bloodstream.

Lipids (fats)

Some lingual and gastric lipases (fat digesting enzymes) have already been at work, but the major job of fat digestion takes place in the small bowel.
Again, if fats are consumed uncooked or unprocessed or if supplemental digestive enzymes are consumed with the meal, the equation changes. But in lieu of
that, at this point in the process, fats are composed mainly of triglycerides (three fatty acids bound to glycerine). It is the action of pancreatic lipase
in the small bowel that breaks them down into smaller, potentially absorbable components. Specifically, pancreatic lipase splits off a monoglyceride,
leaving two of the lipids still attached to the glycerine.

To a significant degree, the ability of pancreatic lipase to break down lipids is regulated by how soluble those fats have become. It should be noted that
lipids in their natural state are not water-soluble (that is, they do not dissolve in water). This is where bile, regulated by the gallbladder, comes into
play. Bile salts (from the liver and gallbladder) emulsify (break into small droplets) the fat for easier entry into water solutions -- or more
technically, into water suspensions. If you have gallstones, or have had your gallbladder removed, you will tend to have incomplete breakdown of lipids in
your small intestine, resulting in fatty stools and a tendency to intestinal discomfort. In addition, and even more important, malabsorption of lipids
prevents the body from receiving any of the nutrients dissolved in the fat. We're talking about vitamins A, E, and D, tocotrienols, and Omega-3 fatty acids
to name some of the more familiar ones.

Carbohydrates

Unless you chewed your food properly (to pick up amylase from your saliva), or took supplemental enzymes with your meal, carbohydrates, for the most part,
enter the small intestine intact. Once there, however, they are cleaved into sugars by pancreatic amylase. Further down the small bowel, maltase, sucrase, lactase, isomaltase and alpha dextrinas, secreted by the brush border cells, act on the remaining carbohydrates,
cleaving off the component simple sugars one Sugar at a time. For example:

• 
  Maltase acts on maltose -- cleaving it into its component parts, glucose and glucose.
  


• 
  Sucrase acts on sucrose -- cleaving it into glucose and fructose.
  


• 
  Lactase acts on lactose -- cleaving it into its component parts, glucose and galactose. Note: if lactase levels are insufficient, lactose intolerance
  develops. Bacteria ferment the unbroken lactose, and excess gas is produced.
  

Note: pancreatic lipase and amylase in the blood are used to measure abnormal function of damaged pancreatic cells.

Absorption

Again, everything we've talked about so far is about preparing the chyme for absorption into the bloodstream. Ninety to ninety-five percent of nutrition is
absorbed in the small bowel. By the time chyme has reached the small intestine, it has been mechanically broken down and reduced to a liquid by chewing and
by mechanical grinding in the stomach. In addition, partial chemical digestion may already have taken place as the result of enzymes in the food itself and
enzymes found in saliva. As discussed previously, the effect of those enzymes can be extensive (up to 70% of total digestion) or virtually non-existent
depending on how cooked and processed the food is and how much it is chewed. The use of supplemental digestive enzymes, of course, can change that equation
dramatically. And finally, the action of stomach acids and pepsin serve to denature proteins and begin the process of breaking them down, making them
readily amenable to final breakdown in the small intestine.

Thus, once inside the small intestine, the "partially" digested chyme is exposed to pancreatic enzymes and bile, which ultimately break down the chyme into
"component" forms of protein, carbohydrates, and fats capable of being absorbed.

By the end of its passage through the small intestine, virtually everything of value to the body has been extracted from the chyme. We're talking about:

• 
  Water
  


• 
  Electrolytes (sodium, chloride, potassium)
  


• 
  Proteins, carbohydrates, and fats (which have been broken down respectively into amino acids, glucose, and fatty acids)
  


• 
  Vitamins, minerals, antioxidants, and phytochemicals
  

Let's now look at this process in detail.

The absorption of water in the intestinal tract

Virtually all of the water that enters your intestinal tract, in whatever form, is absorbed into the body across the walls of the small intestine --
primarily through the action of osmosis. Incidentally, osmosis is defined as

the movement of water across a semi-permeable membrane from an area of high water potential (closer to distilled water) to an area of low water
potential (water that contains a lot of dissolved osmotically active molecules such as electrolytes and some nutrients)

. Incidentally, since its molecules are so large, the chyme that enters the intestinal tract from the stomach has only a minimal impact on osmotic
pressure. However, as it is progressively broken down, its ability to increase osmotic pressure rises dramatically. For example, undigested starch has
little effect on osmotic pressure, but as it is digested, each starch molecule breaks down into thousands of molecules of maltose, each of which is as
osmotically active as the single original starch molecule. The net effect is to increase the osmotic pressure by a factor of several thousand times over
the original starch molecule. Thus, as digestion proceeds, the osmotic pressure increases dramatically, thereby pulling water into the small intestine. In
addition, crypt cells at the base of each villus (in the duodenum and jejunum) secrete electrolytes (chloride, sodium, and potassium) into the small
intestine which further increases the osmotic pressure to pull water into the lumen (the empty space in the small intestine). On the other hand, as the
osmotically active molecules (maltose, glucose, amino acids, and electrolytes) are absorbed out of the lumen and into the bloodstream, osmotic pressure
decreases relative to the electrolyte rich water of the bloodstream, and water is thus reabsorbed back into the body.

The bottom line is that if the secretion and absorption of water doesn't balance, we become either bloated or dehydrated. With that in mind, we can take a
look at a water balance sheet.

Thus we can see that the water that enters the digestive tract and that is used in the digestive process is matched to a remarkable degree by the water
that is recycled and excreted. In a healthy body, they are perfectly balanced, give or take a tenth of a liter. Keep in mind that the water lost through
other means needs to be accounted for in balancing intake and outflow for the entire body. Sweat, for example, can account for anywhere from 100 to 8,000
ml (about 8.5 quarts) lost per day. You lose another quart as water vapor that passes out of your body as you breathe each day -- as anyone knows who
watches their breath on a cold day. The amount lost in your urine will pretty much balance out the difference between the amount above and beyond the bare
2.3 liters you consume in your drink and food and the tenth of a liter lost in your feces and what you lose in your perspiration and breath. The bottom
line is that your body will seek to balance the intake and outflow of the water it deals with every day -- to prevent bloating or dehydration. At any point
it fails to do so, you will end up visiting your doctor.

Keep in mind that even small imbalances between fluid intake and output can cause major problems. Diarrhea is a common symptom of disease and can kill
patients through dehydration. On the other hand, rapid over-consumption of water or other liquids, though rare, can cause a rapid drop in sodium and
electrolyte levels in the bloodstream and can cause death. Or if your body loses the ability to effectively pass water through your kidneys, you suffer
from edema (swelling in your legs), which puts an added burden on your heart.

So, how much water should you drink in addition to what you get
in your food? Despite some medical claims to the contrary, I'm still a big fan of 64 ounces a day -- give or take, as circumstances dictate (body weight,
temperature, how much you perspire, etc.).

Conclusion

Let's break here for now. In our next issue of the newsletter, we will focus on the fascinating topic of how your small intestine actually recognizes and
absorbs specific nutrients after preparation by the digestive process. We will also discuss some of the things that can go wrong and what you can do to
prevent or even reverse them.

Physiology of the Small Intestine, Part 2

In this newsletter, we return to our exploration of the intestinal tract from a natural health perspective, but this time we shift gears a bit. So far, we’ve covered everything from the mouth through the duodenum (taking time to discuss the ancillary outpouchings along the way: the pancreas, liver, and gallbladder). And throughout, the emphasis has been on digestion. But now as we reach the small intestine, things change. Absorption becomes the dominant issue. Yes, a great deal of digestion still occurs in the small intestine, and we will cover that, but the overall emphasis is on absorption. In fact, if you ignore exceptions like the direct absorption of alcohol from an empty stomach, close to 100% of all nutrient absorption in the human body takes place in the small intestine. Obviously then, its proper functioning is crucial to our health.



In this issue, we will explore the anatomy of the small intestine to give us a functional understanding of how it is constructed to do its job and also provide us with a shared vocabulary that we can subsequently use as we explore exactly how the small intestine completes digestion of food and selectively absorbs the nutrients your body needs.



Macro anatomy of the small intestine



The small intestine, also called the small bowel, serves two primary functions in the body.



• If the diet consists primarily of cooked and refined

carbohydrates and fats, and if no supplemental enzymes are taken with your meals, these compounds will be mostly intact when they reach the small intestine.

Digestive juices in the stomach work on proteins, not carbs and fats. That means that for most people, the

small intestine is the final stage for the enzymatic digestion of carbohydrates and fats – keeping in mind that

oftentimes they are never fully digested and pass unabsorbed into the bowel where they contribute to gas and

bloating as bacteria begin to work on them.

• That said, the primary role of the small intestine is the absorption of nutrients broken down by digestion.

These include, the absorption of:





• Proteins (amino acids)

• Carbohydrates (monosaccharides)

• Fats (lipids)

• Vitamins

• Minerals

• Enzymes

• Water





Technically, the small intestine begins at the pylorus valve that separates the stomach from the duodenum and ends at the ileocecal valve that separates the ileum from the large intestine. The bulk of the small intestine is suspended from the body wall by an extension of the peritoneum called the mesentery. The small intestine is approximately 20-23 feet long, depending on how and when it’s measured, and it is divided into three sections:



• Duodenum

• Jejunum

• Ileum





Although precise boundaries between these three segments of bowel are not readily observed, there are microscopic structural differences among them.



Duodenum

The name duodenum actually derives from its length and literally means “twelve” inches. It runs from the pylorus valve to the ligament of Treitz (a band of smooth muscle that extends to the diaphragm and works to hold the small intestine in place). Although technically part of the small intestine, the duodenum is almost 100% involved in digestion, not absorption. As such, we have discussed it in great detail already and will not focus on it in this newsletter.



Jejunum



The jejunum runs from the ligament of Treitz to the mid-small bowel and encompasses roughly 40% of the length of the small intestine. It has numerous muscular folds called plicae circulares, and we will explore it in some detail in the next newsletter. The term "jejunum" derives from the Latin and means "empty of food." The name, however, actually came from the ancient Greeks who noticed that at death this part of the intestine was always “empty of food.” Hence, the name jejunum.



Ileum



The third division of the small intestine is the ileum, which runs from the mid-small bowel to the ileocecal valve at the entrance to the large bowel (colon) and encompasses roughly 60% of the length of the small intestine. The word "ileum" comes from the ancient Greek and means "twisted," which actually has a dual meaning. First, when viewed during surgery (or after a Trojan sword has slit open your midsection), the ileum actually looks twisted. The second reference is that the ileum is most often the site of twists that can cause obstructions in the small intestine.



Pilcae circulares



As mentioned above, when referencing the jejunum, the small intestine is not flat internally, but is thrown into circular folds. These folds are known as “plicae circulares” and are prominent inside the small intestine from the duodenum to the mid-ileum. They serve a dual purpose:



• They increase surface area for enhanced absorption.

• They cause the chyme to move through the small intestine in a corkscrew motion, which aids in mixing the

chyme. Effectively, the folds act as baffles.



Blood supply of the small intestine



Identifying the blood supply of the small intestine is more important for surgeons than for our discussion of the small intestine as it relates to natural health. Nevertheless, very quickly:



• The duodenum is supplied by the gastroduodenal artery and by branches of the superior mesenteric artery.

• The jejunum is supplied by jejunal branches of the superior mesenteric artery.

• The ileum is supplied by the ileal, right colic, ileocolic, and appendiceal branches of the superior mesenteric

artery.





The microstructure of the small intestine



If examined closely, the surface of the small intestine has the appearance of soft velvet. This is because it's covered by millions of small projections called villi which extend about 1 mm into the lumen (the empty space inside the small intestine). But villi are only the most obvious feature of the intestinal wall. As we’ve already discussed, the mucosa (the innermost layer of the intestinal wall) contains a number of different cells including: a self-renewing population of epithelial cells, secretory cells, and endocrine cells. Let’s look at the intestinal wall in a little more detail.



The small intestine has the same four layers as the rest of the GI tract, but they are modified for maximal absorptive power.

• Serosa -- the peritoneal covering of the external surface of the small intestine

• Muscularis – the muscle layer that governs peristalsis. In particular, it contains:

• A thin layer of longitudinal muscles that stretches the intestine

• A thicker layer of circular muscles that closes off sections of the intestine as required to allow the

intestine to work, move, and grind the chyme in that section over and over before it releases it into the next

section of the small intestine…where the process repeats again. We will explore this action in more detail

in the next newsletter. (Note: paralytic ileus is the absence of normal GI tract muscle contractions

(peristalsis) and can be caused by anything that irritates the peritoneum sufficiently.)

• Myenteric plexi of Auerbachb, which coordinate peristalsis. Specifically, the plexi (intersecting groups

of nerve cells) are located in the longitudinal muscle layer of the small intestine. The nerve cells in each

plexus primarily project to the circular muscle layer and play an important role in regulating gut motility.

• Submucosa – connective tissue. The submucosa consists of dense connective tissue, although fat cells

may be present. In fact, all three sections of the small intestine (the duodenum, the jejunum, and the ileum)

are all characterized by modifications of the submucosa. The submucosa in the small intestine contains:

• Arterioles, venules, and lymphatic vessels (lacteals) that regulate the flow of blood and lymph fluids

going to and from the mucosa of the small intestine. As a side note, the lymphatic vessels also play a key

role in the absorption of fats from the small intestine, something we’ll talk more about a bit later.

• Mucosa – villi. This is the grand prize, where most of the action in the small intestine takes place.

Accordingly, we will now focus on this layer.



Villi



Villi are projections into the lumen covered predominantly with mature, absorptive enterocytes, along with a spattering of mucus-secreting goblet cells. These cells live only for a few days, die and are shed into the lumen to become part of the chyme where they are digested and absorbed. And yes, if you wish to think of it that way, we are all cannibals eating our own intestinal walls. The word villi literally means “tuft of hair,” which is exactly what the villi look like. In fact, they are fingerlike projections of the mucosa, with approximately 40 villi/sq mm inside the wall of the small intestine. As discussed earlier, each single villus contains an arterial and venus capillary (arteriole and venule) and a lacteal (the lymphatic equivalent of a capillary). Note: the lymphatic system is a circulatory system that exchanges fluid between cells, drains into veins in the neck, and can absorb fat. In the small intestine, the lacteals transport fat from the digestive tract into the circulatory system.



Microstructure of a single villus



Each villus contains multiple absorptive cells on its surface. And protruding from the surface of these absorptive cells on each villus are a vast multitude of microvilli. Microvilli are minutely small hair-like projections that serve to increase the surface area of each villus.

How many microvilli are we talking about?



Hold your breath. Each villus has approximately 200 million microvilli/sq mm. This creates a velvety surface on the walls of the small intestine known as the brush border.



And how much does the brush border of microvilli increase the surface area of the wall of the small intestine involved in nutrient absorption?



Again, hold your breath.



All in all, if the small intestine is viewed as a simple pipe, its surface area totals about half a square meter. But it is not a simple pipe. Factor in the mucosal folds, the villi, and the microvilli, and the absorptive surface area of the small intestine is in fact approximately 250 square meters - the size of a tennis court! This increases the absorptive power of the small intestine exponentially.



Intestinal glands are located in the crypts of Lieberkuhn at the base of the villus (see illustration above). The cells/glands here secrete intestinal juices. Toward the base of the crypts are stem cells, which continually divide and provide the source of all the epithelial cells in the crypts and on the villi. The way they divide is actually quite interesting. One daughter cell from each stem cell division is retained as a stem cell – thus perpetuating the untainted original source. The other daughter cell differentiates along one of four pathways to become either an enterocyte, an enteroendocrine cell, a goblet cell, or a Paneth cell. Enterocyte cells migrate up the crypts, and onto the villi, where they become the mature epithelial absorptive cells essential for extracting nutrients from the chyme. Virtually all nutrients, including all amino acids and sugars, enter the body across these absorptive cells that form the epithelium covering the villi.



Note: After crossing the epithelium of the villi, most nutritional molecules diffuse into the capillary network inside the villus diagrammed above, and then into the bloodstream. Some molecules, fats in particular, are transported not into capillaries, but rather into the lymphatic vessels (lacteals), which drain from the intestine and rapidly flow into blood via the thoracic duct.



Specifically, cells/glands found in the crypts of Lieberkuhn, at the base of villi, include:



• Paneth cells are in the deepest part of the glands. They secrete lysozyme (a bacteriocidal enzyme), and they

are phagocytes. Their purpose is to protect against invaders that have made their way into the intestinal tract

along with the food we eat.

• Enteroendocrine glands are the deepest part of the glands. The cells here secrete three hormones: secretin

(S-cells), CCK (CCK-cells), and gastric inhibitory peptide (K-cells).

• Brunner’s glands are in the deepest part of the duodenal mucosa. They secrete alkaline mucous to neutralize

acid.

• Goblet cells secrete lubricating mucous.

• Peyer’s patches are sections of lymphatic tissue that detect foreign elements in the GI tract and signal the

immune system. (Again, you can bring a lot of bad stuff in through your mouth that needs to be dealt with.)





Ileocecal valve

The ileocecal valve is a small muscle located on the right side of the body (left side on most illustrations) between the small and large intestine, thus marking the end of the small intestine. It is essentially a one way check valve that allows the final stage of chyme to pass into the large intestine for final water extraction and stool making. (Note: once chyme enters the large intestine, it is called fecal matter.) If functioning properly, the valve will open and close as required. Unfortunately, it doesn’t always function properly. Sometimes it sticks in the open position, which allows fecal matter to back up into the small intestine, where it can then contaminate the nutrient extraction process. And sometimes the valve sticks in the closed position, which can lead to constipation. Both of these conditions are very toxic and are easily triggered by bad diet (heavy alcohol consumption in particular), dehydration, and stress.



It should be noted that problems with the ileocecal valve are, for the most part, not acknowledged by the medical community, almost never diagnosed, and no effective treatments are offered. Fortunately, there are highly effective natural health options.



• Chiropractic and homeopathic treatments

• Self massage

• Dietary changes





Conclusion



In our next issue of the newsletter, we will begin an exploration of exactly how the small intestine (based on its anatomy) does its job -- both mechanically and chemically. We will also discuss its physiology, what can go wrong, and how we can fix it…without the need for surgery or debilitating pharmaceutical drugs.





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