Understanding the Human Digestive System:
Part 3--Probiotics: Bifidus and the Large Intestine

Welcome to chapter four of our Journey to Better Nutrition!

In this discussion we deepen our knowledge and experience about how nutrition works inside the human body. This will lead us naturally and organically into a conversation about how Simplexity nutrition products work inside the human body. The main purpose behind this and all our nutrition conversations is to assist you in experiencing optimum product benefits and results. And all of this is designed to be an integral part of your enthusiastic commitment to creating a healthier diet and lifestyle.

Review part 2 of Understanding the Human Digestive System.

"Alexander Fleming, who discovered penicillin, did caution his fellow scientists at the time that penicillin did not kill all bacteria, and that certain strains would easily become penicillin-resistant in time. What Fleming and the other microbe-hunters did not realize was that antibiotic-resistance (on the part of pathogenic bacteria) was not their only worry. They failed to see that when antibiotics kill or inhibit the growth of harmful disease-causing bacteria (strep, staph, e-coli, etc.), they also kill or inhibit the growth of helpful (probiotic) strains like acidophilus and bifidus.

"When this occurs, the garden within is so altered that in many persons, the weeds start to take over (the weeds are the pathogenic and unfriendly bacteria and other negatively inclined and very opportunistic microbes). One of the most common weeds is a yeast called Candida albicans. Another is an organism called Clostridium, which is the source of toxins that cause botulism. Others include those that cause salmonella and Shigella diarrheas. These opportunistic organisms, once they gain a foothold and start growing, can cause a wide range of health problems, ranging from recurring yeast infections to depression, chronic fatigue, sinusitis, and a complex array of illnesses and diseases. It should also be noted that this is not just a problem for humans. Veterinarians, farmers, and microbiologists see problems of a similar nature in cows, horses, poultry, and a variety of pets when they receive feed containing antibiotics."

Keith W. Sehnert, M.D., The Garden Within

The Physiology of Digestion

In chapters two and three we began our exploration of the physiology of the human digestive system. We talked about digestive enzymes in chapter two, and the all-important initial stages of digestion in the mouth and stomach. In chapter three, our journey took us down the long and winding road of our small intestine, as we learned the important role that beneficial bacteria in general, and acidophilus in particular, play in helping us maintain a properly functioning digestive system. Let's see what happens next.

By the time the digested food (chyme) reaches the end of the small intestine, most of the nutrients have been absorbed, if the small intestine is working properly, that is. At the end of the small intestine exists a very interesting and important physiological juncture: the ileocecal valve. The ileocecal valve marks the connecting point between the final section of the small intestine (the ileum) and the beginning section of the large intestine (the cecum), called the ascending colon.

The ileocecal valve, like its predecessor valves from earlier in the gastrointestinal (GI) tract, is a fleshy partition that opens and closes, allowing digested food to pass through. At this particular juncture most of the nutrients have already been absorbed and assimilated, and what remains is mostly waste and water. It's important to normal metabolic functioning that some of this water is reabsorbed into the body…but none of the waste! The large intestine (or colon) is primarily responsible for the rapid transit and effective removal of waste that is a by-product of human digestion.

Also at this junction (of the large and small intestines) is a very familiar piece of our anatomy and physiology: the appendix. It was thought for years to be largely unnecessary in function and therefore medically expendable and useless. But the appendix now appears to play a crucial role in the initial stages of fecal elimination by storing and secreting a variety of substances that support the rapid transit and removal of toxic waste from the colon, and inhibit the growth of any pathogenic bacteria. We are finally learning that when it comes to the miracle of the human body, there are no expendable parts…only essential pieces of a magnificent puzzle that we do not yet fully understand.

Bifidus and the Large Intestine

Bifidus (Bifidobacterium bifidus) is the dominant probiotic bacteria inhabiting the large intestine and is vital to its proper functioning. Let's take a closer look at the basic structure and function of the large intestine and the role that bifidus is designed to play.

There are three primary sections of the large intestine. Each section is about two feet in length: the ascending colon, the transverse colon, and the descending colon. The last six to nine inches of the descending colon is called the sigmoid colon, which is a reference to its shape in that it moves in two directions, like the letter S. When the sigmoid colon is working smoothly and the entire large intestine is healthy, waste matter can be eliminated quickly and easily. The entire intestinal tube terminates with the rectum and anus. The anus is defined by its fleshy sphincter-like ability to expand and contract, and is related in form and function to all the other digestive system "valves" before it.

Unlike its predecessor, the large intestine is relatively short and only about six to seven feet long and about one-and-a-half to two inches wide. The walls of the large intestine are lined with a layer of mucus providing essential lubrication for the rapid transit of waste. Where the small intestine was marked by the presence of protruding villi and microvilli by the millions, the large intestine is made up of a continuous series of very muscular pouches (haustra) which contract due to intestinal peristalsis. These muscular waves of motion move the waste forward to its final destination.

When bifidus and other probiotics, enzymes, and water are absent from this final and most important stage of digestion and elimination, the mucus lining of the large intestine becomes weak or disappears altogether. This situation causes the remaining fecal matter (waste) to become dry and hard. This causes the fecal transit time to slow down, allowing for the proliferation of pathogenic bacteria, which in turn allows for the accumulation of fecal matter in the various folds and pouches of the lining of the large intestine. This situation is responsible for the condition we call constipation, which is basically the result of a sluggish, ill-functioning, and weakened bowel. This situation is also responsible for the thickening and expansion of the large intestinal wall, called diverticulosis, and for the swelling and inflammation of the same, called diverticulitis and colitis. Although there are several other maladies that can occur as a result of this situation, these are the most well-known and most commonly experienced.

What are the specific benefits attributed to Bifidus?

A high concentration of Bifidus in the large intestine can help prevent all the various symptoms of an irritable bowel, and can provide the following important benefits.

1. Bifidus bacteria help to regulate and maintain the proper pH of the large intestine. This balance is essential for normal functioning. The proper pH of various parts of our internal ecology is one of the most important means the body has in maintaining homeostasis (or systemic balance).
2. Bifidus bacteria are helpful in serving as co-factors to various other beneficial bacteria, as well as various food and digestive enzymes, in making sure that all waste matter is thoroughly broken down and stays relatively soft and moist and able to be easily transported up, across, down, and then out of the large intestine.
3. Bifidus bacteria inhibit the growth of pathogenic bacteria, by their sheer numbers on the one hand and by their secretion of natural antibiotics on the other.
4. Bifidus bacteria live in and support the health of the mucus lining of the large intestine. It is the gradual weakening of this lining, through the absence of bifidus bacteria and the presence of many other toxic and insulting factors, that is primarily responsible for the many problems that can occur in the colon.
5. Bifidus bacteria service and protect the many lymph nodes that line the large intestine. These lymph nodes are essential components of the human immune system and are currently the target of much research on the topic of gut-brain-immune function.

Insults to our probiotic and digestive system health can include:

Antibiotics, alcohol, antacids, pharmaceutical drugs, coffee, tea, all sources of caffeine, chlorine in our drinking water (and in our bathing water), chronic dehydration, lack of exercise, too much negative stress in the forms of worry and anxiety, not enough sleep, overeating, anti-depressant drugs, carbonated beverages of all kinds (even carbonated water!), cigarettes, any inhaled tobacco smoke, chewing tobacco, most commercial grade tobacco products, processed foods in general, food additives such as preservatives, coloring agents, flavor enhancers, and artificial sweeteners, dairy products, microwave ovens, excess sugar in any form, excess consumption of fruit juices from concentrates, excess meat consumption, excess flour products consumption (breads, pastries, baked goods using flour, etc.), exposure to environmental pollutants, solvents, chemical cleaning agents, pesticides, herbicides, fungicides, petro-chemical out-gassing from plastics in various building materials and supplies including carpets, flooring, and wallboards, glues, magic markers, clothes made from certain synthetic fibers, paints, paint thinners, eating too late at night, eating or drinking anything too cold, not chewing enough, and many more.

Of course there is much more we can learn about the human digestive system and how best to nourish, support, and strengthen it. We trust that this part of our Journey to Better Nutrition has inspired your curiosity and interest in taking actions that support the proper functioning of this all-important system of the human body, the digestive system.

Action Steps for Chapter 4!

1. Learn more about Simplexity Health's Bifidus.
2. Learn more about probiotics.
3. Fill out your Weekly Benefits Chart.
4. Identify an insulting habit in your diet or lifestyle and minimize its impact. You could eliminate the insult altogether or simply modify it. Just try it one day at a time, for one week, and see if you notice improvements in your health and energy. Also identify a new complementary habit in your diet and lifestyle, and optimize its impact. Review the Habits of Naturally Healthy People for suggestions.
5. Make sure you do something that really makes you laugh every day!
6. Got questions?