This post was originally written during my 2 1/2 year tenure as a blogger for Health Goes Strong. The site was deactivated on July 1, 2013, so the post has been reproduced here.
TO NOURISH THE FRIENDLY BACTERIA IN THE GUT WE NEED TO EAT PREBIOTICS
I came across a statistic in an article about bacteria in the gut the other day that forced me to stop and read it again. Then on second reading I had to underline it to help make it sink in. The article said a healthy adult intestinal tract has over 100 trillion bacterial organisms residing in it. That’s enough to weigh between four to five pounds if we could harvest them from our guts and put them on a scale! Another way to look at it is that there are 10 times more bacterial cells in the intestinal tract than the number of cells in the rest of our bodies (10 trillion).
A growing body of scientific evidence shows that all those microbes can do us some good. But we’ve got to feed them.
Prebiotics are compounds found in the foods we eat that are needed by the friendly bacteria living within us. They provide us with no nutritional value and are indigestible by humans; prebiotics simply nourish bacteria. The advantage to us is that when those bacteria thrive (because they have enough prebiotics) they can, in turn, improve the health of their host – which is you and me.
Some of the ways the friendly bacteria in the gut can help us is by:
- improving absorption of calcium and other minerals
- producing vitamin K
- strengthening the immune system
- preventing the growth of harmful bacteria
- digesting unused energy substrates (such as lactose and certain starches and fibers)
- maintaining bowel regularity
- absorbing water from the gut (prevents diarrhea)
- reducing colorectal cancer risk
For those suffering from inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis, there is also some evidence to suggest prebiotics may be beneficial.
Prebiotics are found naturally in many foods and food scientists can isolate them from non-edible plant materials, like stems and husks, so they can be incorporated into foods we do eat. These prebiotic additions to food are usually flavorless so we can’t detect them and designed to withstand heat so they can be cooked or heat-processed. Some are also being sold as supplements.
Inulin is the most abundant type of prebiotic found in foods we eat, including garlic, onions, leeks, asparagus, banana, and whole wheat flour. Chicory root has the most inulin, but since we eat little of that it is extracted and added to other foods.
Oligosaccharides are naturally found in soybeans and soy products such as tofu, soy milk and tempeh. They also can be synthesized from the milk sugar lactose.
Fructooligosaccharide is most abundant in Jerusalem artichoke and is foun in barely, wheat, jicama, and other fruits and vegetables.
It is important to note that prebiotics are quite different from the probiotics found in yogurts and other fermented foods. Probiotics are live bacteria that, when consumed, can benefit the host. I’ll come back to them another time.