Once you go through the next gateway (The ileocecal sphincter) on your adventurous journey, you find yourself in the midst of a majestic and magnificent forest. You can tell that you are still in some sort of tunnel, but it is completely different from the one that you just left. It is so much bigger! And instead of stalactites there are trees! Everything is so beautiful and an overwhelming feeling of harmony washes over you.

( Checkout part 1: You are Not Only What You Eat; part 2: Our Digestive Tract is Like the London Tube; part 3: The Mouth – Goes Chew, Chew, Chew; part 4: The Stomach – Gastric Food Processor; part 5: Small Intestine – Grand Central Station of Digestion; part 6: Intestinal Immune System – Your Personal Secret Service )

Then an elf-like creature springs out from behind one of the incredible trees. She too ends up in front of you and gracefully performs a deep and elegant bow in front of you.

“Greetings Your Highness, I belong to a group defender and helper elves and it would be my greatest honor if I could act as your guide through this kingdom, the Large Intestine and introduce you to its inhabitants – the Colony of the Colon.

I am a species of beneficial bacteria. You have over 1000 species like me serving you, but this is where myself and most of the population of your beneficial bacteria reside.”

We are quite fortunate that our digestive process, at this point, is almost entirely taken over by handy little helpers. We just have to sit back and let them do the work and we reap the rewards. At this point we are quite happy to have such a pleasant tour guide showing us the features of the large intestine.

“The role of the good people of this kingdom – the many species of beneficial bacteria, like myself, has been largely ignored by your ‘conventional’ science and medicine until recently. Fortunately, this has not been the case in many other cultures where fermentation with microorganisms has been taken seriously. In these cultures, it has become a part almost of their daily diet. The Okinawans that were mentioned to you earlier utilize fermented foods as a significant part of their diet. Our significance is being rediscovered in your modern science and medicine. Some modern studies have even coined the collection of colon microorganisms as “the lost organ.”

The average person has between 5 – 8 pounds (2.3 – 3.6 Kg) of microorganisms in their gut. As you were told earlier, this mass of microorganisms has been shown to be made up of over 1000 different species – a majority of which your scientists have not even given names to! The amount of microorganisms in your body outnumbers your human cells by at least a factor of 10, while our DNA outnumber yours by a factor of 100 times. Even though some of these organisms can be bad in certain situations, the vast majority of us are just another arm of your personal secret service. We not only protect you, but we do many of the housekeeping chores so that you don’t have to.

Now as Dr. Terry mentioned before, when you travel from the small intestine to the large intestine, the environment changes from alkaline to acid. This means that the organisms living in the large intestine are completely different from the ones in the small intestine. The large intestinal bacteria, like myself, are acid loving. We are also present in much larger numbers.

This means that you do not want the bacteria from the large intestine to leak backwards into the small intestine. This is why you have a sphincter called the ileocecal sphincter. You travelled through this sphincter when you moved from the smaller tunnel kingdom of the Small Intestine, to this kingdom of the Large Intestine. If the colon’s microorganisms get into the small intestine, you can get small intestinal bacteria overgrowth (SIBO), which is a major cause of acid reflux, IBS and other health issues.

This means that you want us bacteria to stay in our native kingdoms. When my people, the bacteria of the Large Intestine stay in our kingdom (or colony of the colon), we can do great work and be incredibly beneficial for you. Some of the things that we do are:

• Ferment carbohydrates that the human body is otherwise unable to process.
• Produce biotin, vitamin K, and other essential nutrients.
• Produce short-chain fatty acids that increase the gut’s absorption of water.
• Regrow gut cells in the colon.
• Provide defense against colon cancer and inflammatory bowel disease.
• Rebalance the immune system when it gets off kilter.
• Help train the immune system to recognize who the good microorganisms are and who are not.
• Reduce inflammation.
• Reduce pathogens in the gut.
• Stimulate and improve metabolic function.
• Reduce gas production.
• Prevent tumor growth, as we have antitumor properties.
• Aid in weight maintenance.
• Help mental and intellectual processing.
• To help prevent the bad looters and vandal microorganisms from moving in and setting up shop.

Even though you can live without many of these microorganisms, most of us are incredibly helpful and we make life a lot easier and smoother for you! Living with even low numbers of us can quickly lead to all kinds of illnesses for you.

As you were told earlier, we are very sensitive to your diet and your environment. Different species groups can change in dominance in as little as 48 hours, when you change your diet dramatically. Again, it is significant to remember that your diet determines the ecological balance of your body. It is simple.  Eat too much refined dairy, flour, and especially industrial sweets and large amounts of alcohol, you will get an overgrowth of yeasts like Candida albicans. Reduce (and often completely eliminate these for while), and eat nutritious foods full of healthy nutrient and fiber, and balance can be obtained again. Often, you have to introduce large numbers of the friendly organism (called probiotics) into your system to train us other organisms to get back on track. You can do this easily with supplements or by eating fermented foods, like your ancestors did. In our modern era we often need to do both.

The large intestine also absorbs some of the vitamins both from the original food and from what is produced by the microorganisms. This is where most of the water is absorbed out of the mass so that your stool is not too runny (diarrhea), and to conserve your body’s water supply. If fecal matter stays in the large intestine too long, it becomes dried out, increasing the problem of constipation.

Now I must say good-bye to you. It has been an honor, and I hope you enjoy the knowledge that myself and the rest of my numerous people are working hard for you.”

Well, now that you have been familiarized with the territory of your large intestine, it is time for us to bring you back out of this journey. You have travelled far and long – this journey usually takes about 24 hours. And don’t worry, we don’t think it necessary that you make the high-dive jump into the toilet bowl. The purpose of this initial journey was to familiarize you with some of the geography (and anatomy) that we will use in the larger adventure of life that we will continue to travel . . .

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