How Prebiotics Work!

Prebiotics are really the new kid on the block. The term was coined in 1995. A prebiotic is a special type of soluble fiber that is used mostly by the beneficial good bacteria as a fuel. These good bacteria, in turn, produce certain substances that acidify the colon (a very good thing) and serve as a nutrition source for the colon’s own cells. Isn’t this remarkable? The colon provides a warm, oxygen-free environment for these beneficial bacteria to grow. These bacteria, in turn, manufacture the nutrition source for the colon itself. This is a true symbiotic relationship where both the bacteria and colon depend on each other and promote each others’ health. Of course, the body benefits even more as some, rather remarkable health benefits occur when this system is operating maximally.

So what are prebiotics? The ones with the most science behind them are inulin and oligofructose. Inulin, itself, is remarkable in that it has been around in the plant world for a very long time. It has been found in over 36,000 different plants, so it somehow has been a vital food source for plant-eating animals and humans for a very long time. Interestingly, as our food industries and agriculture have developed, the foods in which we get inulin have become limited.

We now find inulin in wheat, onions, bananas, garlic, leeks, chicory root, Jerusalem artichokes, wild yam, agave, and jicama.

In the U.S., most people get very little of this valuable fiber, perhaps only 2-3 grams a day on average with 70% of this coming from wheat and 20% from onions. Europeans eat three to five times this amount of inulin-containing foods.


A prebiotic:

  1. is not digested by the small intestine
  2. is used as fuel, or fermented, by some colon bacteria
  3. produces health benefits by objective measurements

According to some leading authorities, only inulin and oligofructose have fulfilled these three criteria. There are only a few others, but none with as much medical research.

So, the proven prebiotics fibers are a relatively new discovery. More than this, they have been found by careful research to provide significant health benefits, not only to the colon but to the body as a whole.


Prebiotic Foods List

  • apples
  • asparagus
  • artichokes
  • banana
  • berries
  • black beans
  • cherries
  • dandelion greens
  • chicory root
  • chickpea
  • eggplant
  • endive
  • flaxseeds
  • garlic
  • honey
  • jerusalem artichokes (sunchokes)
  • jicama
  • kefir
  • kiwis
  • leafy greens
  • leeks
  • legumes
  • lentils
  • mangoes
  • oatmeal
  • onions
  • peas
  • pears
  • quinoa
  • radicchio
  • tomatoes
  • white beans
  • whole grains
  • yogurt