Understanding probiotics, prebiotics, and postbiotics—and how each contributes a different piece to the microbiome puzzle.
The terms probiotics, prebiotics, and postbiotics are increasingly common on food, supplement, and wellness products. Although they sound similar, they describe different concepts. Understanding the difference can help consumers make more informed decisions.
What Are Probiotics?
Probiotics are defined by an international scientific consensus as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Importantly, the word "probiotic" does not simply mean "any bacteria." A probiotic microorganism should be appropriately identified, and the evidence supporting a health benefit relates to the particular microorganism and its strain, dose, and intended use. Different probiotic strains can have different properties and should not automatically be assumed to have the same effects.
What Are Prebiotics?
A prebiotic is a substrate that is selectively utilized by host microorganisms and confers a health benefit.
In simpler terms, prebiotics are substances that certain microorganisms can use in ways associated with beneficial effects. Commonly discussed examples include certain types of dietary fibers.
What Are Postbiotics?
Postbiotics are different again. An expert consensus statement from the International Scientific Association for Probiotics and Prebiotics defines a postbiotic as a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host. This means that postbiotics are not simply "dead probiotics." The definition includes specific requirements concerning the preparation and evidence of health benefit.
What About Synbiotics?
Synbiotics combine live microorganisms with substrates selectively utilized by host microorganisms.
They are designed around the interaction between microbial components and substrates rather than simply being a mixture of unrelated ingredients.
Why Does the Difference Matter?
These terms describe different categories:
Probiotic: live microorganisms with demonstrated health benefit in the appropriate context.
Prebiotic: a substrate selectively utilized by host microorganisms that confers a health benefit.
Postbiotic: a preparation of inanimate microorganisms and/or their components that confers a health benefit. Understanding these distinctions is important for scientists, healthcare professionals, manufacturers, and consumers.
The Microbiome Wellness Opportunity
Microbiome science continues to evolve. As research develops, scientists are investigating how microorganisms, their substrates, and microbial-derived components interact with the host.
At Unique Biosciences, our microbiome wellness products are part of our broader interest in the relationship between science, microbial communities, and everyday wellness.
References
- Hill C, Guarner F, Reid G, et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic. Nature Reviews Gastroenterology & Hepatology. 2014;11:506–514. doi:10.1038/nrgastro.2014.66.
- Gibson GR, Hutkins R, Sanders ME, et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics consensus statement on the definition and scope of prebiotics. Nature Reviews Gastroenterology & Hepatology. 2017;14:491–502. doi:10.1038/nrgastro.2017.75.
- Salminen S, Collado MC, Endo A, et al. The International Scientific Association for Probiotics and Prebiotics consensus statement on the definition and scope of postbiotics. Nature Reviews Gastroenterology & Hepatology. 2021;18:649–667. doi:10.1038/s41575-021-00440-6.
- Swanson KS, Gibson GR, Hutkins R, et al. The International Scientific Association for Probiotics and Prebiotics consensus statement on the definition and scope of synbiotics. Nature Reviews Gastroenterology & Hepatology. 2020;17:687–701. doi:10.1038/s41575-020-0344-2.