In my last 2 articles, we talked about what probiotics are and whether you should get them from food or supplement form. The other great thing about probiotics is that they not only help support your immune system, but they also help with bowel regularity, something that is important to everyone!
Today our topic is prebiotics, the fuel for probiotics.

What are Prebiotics?
It’s pretty simple! Prebiotics feed, or stimulate growth of probiotic bacteria (the good bacteria!). They nourish Probiotic bacteria and yeasts so that they stay around in your gut and can grow faster.
Some experts have argued that consuming prebiotics, rather than probiotics is more practical since taking probiotic bacteria by mouth is more unpredictable in how it can survive in each persons GI tract. In contrast, prebiotics are not sensitive to digestive acids or enzymes.
The criteria for classification as a prebiotic are:
- resistant to digestion
- fermented by colon microflora
- able to selectively stimulate growth of good bacteria
- beneficial to the host’s health
Inulin and oligofructose, are the best-studied prebiotics. You may be able to find these in supplement form, usually as
Fructo-Oligosaccharides (FOS) or Inulin. However, you don’t need to take supplements of prebiotics; There are many foods that provide prebiotics!
Inulin and oligofructose are present in varying amounts in more than 36,000 plant foods. For example, there are oligosaccharides in soy, peas, and beans which might be one of the reasons they are cancer-preventive. Fermentation of prebiotics in the colon produces butyrate, which may reduce cancer growth.
Food Sources of Prebiotics:
Excellent food sources of prebiotics are chicory root (roughly 15% to 20% inulin and 5% to
10% oligofructose) and Jerusalem artichokes.
Personally, I have consumed a coffee alternative that was made of chicory root, called Teeccino. I have also seen inulin in some of the dairy free yogurt brands. Most inulin used commercially in foods is extracted from chicory or synthesized from sucrose.
Others sources of prebiotics include:
- wheat,
- barley,
- rye,
- flax,
- oatmeal,
- whole grains,
- onions,
- garlic,
- leeks,
- legumes,
- asparagus,
- greens (dandelion, spinach, collard greens, chard,
kale, mustard greens), - berries,
- bananas
You will notice that basically all of these foods are great sources of fiber. Essentially, and easy way to think about it is that FIBER is a probiotic. It’s the undigestible part of plant foods that pass through your gut, provide fuel for the good bacteria to grow and stay around, and then moves on out as stool!
Bottom Line:
So here’s the bottom line on biotics, both pre and pro:
Eat plenty of sources of prebiotics every day to promote healthy bacteria in your gut. Aim to get 1-2 servings of probiotics each day through fermented foods like yogurt.
The healthy bacteria will help with bowel regularity, and will strengthen the immune functions of your GI tract to reduce your risk for cancer.
Hope you found this helpful!
– Julie