Toggle Nav

Prebiotics: What are they and why do we need them?

prebiotic fruit and vegetables on plates
Highlights
  • Prebiotics are non-digestible dietary fibers that serve as food for probiotics
  • Prebiotics can enhance the metabolic activity and growth of beneficial bacteria
  • When combined, probiotics and prebiotics may have synergistic effects

Chances are, you’ve heard of probiotics—live bacteria and yeasts that perform vital immune and digestive functions in exchange for room and board in our gut.1 We effectively play host to trillions of these living microorganisms, upon whom we are dependent for many life-sustaining functions.1 In fact, research indicates that without a diverse and abundant population of these microbial “guests”, our immune and digestive health would suffer considerably.2

Prebiotics provide nourishment for probiotic bacteria

A concept you may be less familiar with is prebiotics. Basically, prebiotics are molecules in foods (namely, non-digestible carbohydrates) that induce the growth or activity of beneficial microorganisms (i.e., probiotics) in the large intestine.3 In other words, prebiotics provide nourishment for probiotic bacteria, and help facilitate their attachment within the gut.4 Just like we need probiotics to carry out important physiological and metabolic functions, probiotics need prebiotics to function optimally.

And what’s more—research suggests that without a sufficient source of prebiotic fibers, the probiotic bacteria in your gut can look to the intestinal mucosal barrier as a source of carbohydrates.5 Considering you need the intestinal barrier for protection from undesirable gut bacteria and other molecules, that’s (gulp) not great. 

Prebiotics naturally exist in a number of foods

Ok, so how can we get prebiotics? Prebiotics naturally exist in a number of healthy foods, including breastmilk, leeks, garlic, chicory, bananas, asparagus, Jerusalem artichoke, and soybean. And although it’s always preferable to derive nutrients from food, it doesn’t hurt that some high-quality probiotic supplements include added prebiotics (such as fructooligosaccharides (FOS) or inulin) to help ensure that these beneficial microbes make the most out of their stay in the gastrointestinal tract. In fact, when it comes to dietary fibers, research finds that having a diversity of sources is actually better for the gut microbiome than a single type of fiber.6 In other words—the more prebiotic sources, the merrier for your gut.

Synbiotic effect

An additional benefit to prebiotics is that, when combined with probiotics, they can have a synbiotic effect.7 Essentially, this means that certain probiotic strains and prebiotics can provide their host (i.e., you) with even greater benefits when taken in combination than the sum of their effects alone. So do yourself (and your hard-working guests) a favor, and be a gracious host. Make sure to integrate sources of prebiotics into your daily health regimen. 

Gina Jaeger, PhD is a Developmental Specialist and Lead Research Writer for Nordic Naturals. She holds a doctorate in Human Development, and has published several research articles on children's cognitive development. Gina enjoys studying and educating others on strategies for optimizing health and wellness throughout the lifespan.

1. National Institute of Health. 2012.
2. Wang B, et al. Engineering. 2017. 3(1): p. 71-82.
3. DeVrese M, Schrezenmeir J. Adv Biochem Eng Biotechnol. 2008. 111. p. 1-66.
4. Pandey KR, et al. J Food Sci Technol. 2015. 52(12): p. 7577-7587.4. Pandey KR, et al. J Food Sci Technol. 2015. 52(12): p. 7577-7587.
5. Schroeder BO. Gastroenterology Report. 2019. 7(1): p. 3-12.
6. Holscher HD. Gut microbes. 2017. 8(2): p. 172-184.
7. Markowiak P, Slizewska K. Nutrients. 2017. 9. 1021.