Most people now know about the human colon, either by someone’s account of a colonoscopy, by colon polyps or cancer or, perhaps, by the vogue of a high colonic enema. In the end (and isn’t this a bad pun?) the colon has always been a storage site for the waste materials our body does not use. In the past, this is what was taught in medical school, along with the diseases of the colon – cancer, polyps, diverticulosis, irritable bowel syndrome and colitis. It was all pretty simple back then. But things have really changed as our knowledge of the colon and its inhabitants, mostly bacteria, has increased dramatically in the past few years.
What We Know Now
The colon is a warm, moist and mostly oxygen free environment, ideally suited to be the natural home for huge numbers of bacteria that grow and thrive there. In the past 300-400 different species of bacteria were known. We couldn’t be sure of the total number of bacteria but we knew it was a lot. Now, with new research, including the use of DNA probes of the bacteria genetic material, we know there are probably 1000 or more species with the total population of bacteria being tens of trillions. In fact, no other place in the world including the intestinal tracts of any living thing from insects to elephants has such diverse and huge concentrations of bacteria as the human colon. Well, these are remarkable facts. This bacterial makeup within our colon is something we have always had, going back eons of years. The question to ask is why? Why do we have this seething, quiet, cauldron of bacteria within us? Now, as we learn more, it is beginning to make sense. There had to be a beneficial reason for us humans to harbor such a decidedly unusual organ and its contents as the colon.
A Health Organ!
It is now becoming remarkably clear that the colon is a health organ. Its bacterial contents provide health benefits to the colon itself and to the body as a whole. The good bacteria help us a lot. We want to keep these and promote their growth. Some others are nasty customers that we would just as soon not have around, at least in any great numbers.
Feeding Our Bacteria
How do we promote the growth of the good bacteria within the colon? The answer, when you think of it, is pretty obvious. The colon’s bacteria almost all depend on the foods we eat and which do not get used by our own body. For the good bacteria, it is the fiber in plant food that is important. Plant fiber is not digested by the small intestine but rather arrives in the colon just as it left the stomach. We know that certain soluble fiber in plants, vegetables and fruits are the prized source of nutrition for these good bacteria. Yes, food fibers will promote better bowel regularity, which everyone can see and feel. However, the quiet unobserved benefits are far greater than a soft regular bowel movement.
Different Types of Fiber
The easiest way to understand fiber is to know that it comes in two different types. The first is called insoluble fiber. This fiber is not fermented by bacteria but it does hold onto water and so promotes a larger, softer stool. Wheat is a prime example of insoluble fiber. The other major type is soluble fiber. This fiber does dissolve in water, and like insoluble fiber, passes to the colon unchanged. Here, it is the food and fuel that the good bacteria in the colon relish. Oats, the pectins in many fruits, most of the bean types, and the recently discovered prebiotic fibers are chock full of soluble fiber. Please note that a prebiotic is a plant food fiber. It is not a probiotic, which is a bacteria such as is found in yogurt and dairy products.
How Much Fiber Should The Colon Get?
The medical fiber experts tell us that we should be getting 25-35 grams of fiber a day. Fiber only comes from plants. Vegetables and fruits of all types including root vegetables have nutrition, vitamins and minerals, and also a great deal of fiber. Most Americans consume less than 10 grams a day, a very low amount. The fiber intake should be fairly equal between the soluble and insoluble types. Most plant material has both types with some being predominantly one type or the other.
Prebiotics: The Best Soluble Fibers
Virtually all fibers offer some benefit to the bowel. However, those with the most medical research data are certain prebiotic fibers. The one that is most abundant in nature is inulin and its derivative, oligofructose (FOS). These are very widely dispersed in nature, but unfortunately our food industries do not promote or supply them very often. Inulin and FOS are found in the highest concentrations in:
- Chicory root
- Jerusalem artichokes
Americans get about 90% of these beneficial fibers from:
Inulin and FOS are also found in:
- Wild yams and other root vegetables
But…Americans only eat an average 2-3 grams of these prebiotic fibers a day, about a third of what Europeans eat. These are all very low amounts.
What Do Inulin and FOS Do?
Does it make any difference which types of fiber we eat or take as a supplement? The answer appears to be yes it does matter. These prebiotic inulin type fibers have been shown by laboratory, animal and human research studies to:
- Improve bowel regularity
- Substantially increase the good colon bacteria, such as Bifidobacter and Lactobacillus
- Decrease the bad types of bacteria such as Clostridium and Bacteroides species
- Control appetite and perhaps weight
- Reduce occurrence of allergies in infants and children
- Produce vitamins B12 and K
- Reduce triglyceride blood levels
- Increase certain immune factors within the colon wall itself
- Produce substances that the colon’s own cells use for nutrition
- Increase calcium absorption
- Strengthen bones by increasing bone density
- And, oh yes, they even can reduce or eliminate stinky flatus
The Startling Fact – The Colon Helps Keep Us Healthy
So, our colon is, indeed, an amazingly active cauldron of thriving bacteria. It is dramatically clear that these bacteria and we humans live in a mutually beneficial relationship. We help them by ingesting 25-35 grams of fiber each day. They help us by giving us real, medically proven health benefits. There is even emerging information to suggest that diseases of the colon such as polyps and cancer, diverticulosis, irritable bowel syndrome, ulcerative colitis and Crohn’s disease are related in some degree to a malfunction or under function of the bacteria factory within our colon. The conclusion we in medicine are reaching is that modifying our eating habits to significantly increase our plant food intake is a real plus for our bowel and overall health. Please go to our High Fiber Diet for more details.
©Frank W. Jackson, M.D.