It’s the Fiber, Stupid!
Fend off disease with a diet rich in whole grains, fruits and vegetables
Despite the “eat more fiber” campaign sweeping across the nutritional landscape of America, a person living today will likely eat less fiber than at any other time in human history.
In 1900, the average American received more than 30 percent of daily calories from fiber-rich whole-grain products. Today that number is less than one percent. We eat less fiber-rich vegetables and fruits than did our grandparents and our low dietary intake of fiber has been fingered in just about every modern “disease of affluence” known to science, and probably a few others we have not wrapped our arms around yet.
So why don’t Americans eat more fiber? Never mind what fiber is or how it actually works to make us healthier–we want more of it in our diet! At least that’s what we tell the nice people conducting nutritional surveys when they call. Yet, we eat less than half of the 25 to 35 grams a day the government says we should–and for many of us, those numbers keep dropping. The well-intended health message currently associated with fiber is simply not working–time to change the message. I think if consumers actually knew what fiber was really for, they would eat a lot more of it. We would all be healthier, live longer and more active lives, and would save a bundle of money on health care to boot.
Fiber is not food for us, its food for bacteria. As you read this, there are trillions of live bacteria feeding off the remains (fiber) of your last meal–mainly in the last five feet of your gastrointestinal tract–the colon. Humans have evolved with a complex population (500-plus species and counting) of bacteria that feed off the fiber we send down the pipe every day. In fact, the bacteria represent about 90 percent to 95 percent of all the cells in our body. Taken literally then, we are 20 times more microbe than mammal. Think about that for a minute.
The bacteria have been with us every minute of every day from the moment we were born–and will be so until we die. The problem is, our current low-fiber diet is literally starving the bacteria and disrupting the delicate balance between us and our evolutionary hitchhikers. This is not good.
Fiber is technically any food item that cannot be broken down by enzymes in the small intestine, and thus is transferred to the colon–end of the line. Food manufacturers currently use over 100 different “fiber” substances in foods. Once in the colon, the bacteria go to work and break down the fiber by a process known as fermentation–and this is where it gets interesting.
I doubt many of you reading this are aware that nearly 70 percent (dry weight) of the last stool you passed is made up of live and kicking bacteria. Look next time if you don’t believe me! You will need to borrow your neighbor’s scanning electron microscope to see them, however. We also excrete our body weight in these bacteria each year in our feces. The bacteria serve as the first and last line of defense against invading pathogens–think Salmonella. A healthy and growing (read well-fed) population of good bacteria makes your colon more acidic and thus less inviting to invading pathogens. In sufficient numbers, the good bacteria out-compete the invaders for food, making it difficult for the pathogen to grow in sufficient numbers to make you sick.
The soft, bulky and more frequent stools many folks associate with fiber consumption is in fact evidence of a growing and thriving population of bacteria in your colon. Remember, you poop bacteria. A further sign of a healthy, well-fed, population of bacteria in your colon can be measured by the frequency of your flatulents. Though considered anti-social in most circles, “breaking wind” ten or more times a day is a sign of a fiber-rich diet, as the bacteria produce gases as a byproduct of fermenting fiber.
While bulky stools and gas are indicators of a healthy fiber-rich diet, they are not the most important reason you should eat more fiber. An additional byproduct of the fermentation, like the gases, are little compounds known as short chain fatty acids, SCFA for short. These are important compounds only produced by well-fed bacteria. SCFAs are absorbed by the body and serve as energy for the liver, skeletal muscle, brain and importantly, your colon.
The acidic and SCFA-rich environment created by the well-fed bacteria not only protects you from getting sick and provides energy, it also dramatically increases your body’s ability to absorb calcium, thus reducing your risk of osteoporosis, and decreases your bad cholesterol, reducing your risk of coronary heart disease. Further, this bacterial-induced environment has positive effects on biomarkers of colon cancer, reduces symptoms of inflammatory bowel disease and counteracts fat mass development. And the list goes on.
So there you have it. Fiber is food for bacteria that will, if you feed them, protect you from invading pathogens and reduce your risk of a number of ailments and disease. Ignore them, as we have been, and we will continue to be the unhealthiest people on the planet. You might think about eating some fiber today.