April 22, 2024

Postbiotics: What They Are and How They Work

While probiotics and prebiotics have received much attention as dietary supplements, postbiotics are emerging as the new buzz for gut health and beyond. But what exactly are postbiotics, and how do they contribute to human health?

The Basics

  1. Probiotics: These are live microorganisms known for their wide range of wellness benefits, including antimicrobial activity against pathogenic organisms, immune modulation, enhancement of gut barrier integrity, improved gut motility, and the list goes on. They are critical not only in gut health, but also in weight management, cardiometabolic health, women’s health, and more [1].
  2. Prebiotics: Non-digestible fibers that nourish the gut bacteria, leading to the production of short-chain fatty acids (SCFAs). SCFAs are beneficial products of bacterial fermentation, fueling the cells of the large intestine and contributing to intestinal barrier function, modulating inflammation, and regulating metabolism.
  3. Synbiotics: Combinations of probiotics and prebiotics that work synergistically to enhance gut health [2].
  4. Postbiotics: As defined by The International Scientific Association for Probiotics and Prebiotics (ISAPP), a postbiotic is “a preparation of inanimate microorganisms and/or their components that confer a health benefit on the host [3].”

Exploring Postbiotics

Postbiotics encompass non-living microorganisms, their cellular structures, and metabolites that provide health benefits to the host. They exert their effects through various mechanisms, including protection against pathogens, enhancing the gut barrier, immune modulation, and antioxidant activity. Compared to probiotics, postbiotics offer advantages like increased safety, longer shelf-life, and easier standardization [1].

Recent Research and Clinical Evidence

In a 2020 clinical study, non-viable, heat-inactivated Bifidobacterium bifidum showed promise in treating irritable bowel syndrome (IBS). Patients who received this non-living bacteria experienced significant improvements in IBS symptoms, suggesting that postbiotics may be effective in managing gastrointestinal conditions [4].

Challenges and Opportunities

While postbiotics hold immense potential, there is still much to uncover regarding their specific components, concentrations, and mechanisms of action. Further research is needed to address safety concerns, identify biomarkers of efficacy, and optimize delivery methods, presenting exciting opportunities for innovation [1,5].

The Bottom Line

Postbiotics represent a promising avenue for promoting gut health and overall well-being. As research in this field continues to evolve, we can expect to unlock new insights into the therapeutic potential of these microbial components.


  1. Ma L, Tu H, Chen T. Postbiotics in Human Health: A Narrative Review. Nutrients. 2023; 15(2):291. https://doi.org/10.3390/nu15020291
  2. Davani-Davari D, Negahdaripour M, Karimzadeh I, Seifan M, Mohkam M, Masoumi SJ, Berenjian A, Ghasemi Y. Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications. Foods. 2019; 8(3):92. https://doi.org/10.3390/foods8030092
  3. Salminen S, Collado MC, Endo A, et al. The International Scientific Association of Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of postbiotics. Nat Rev Gastroenterol Hepatol. 2021;18(10):649-667. doi:10.1038/s41575-021-00440-6
  4. Andresen V, Gschossmann J, Layer P. Heat-inactivated Bifidobacterium bifidum MIMBb75 (SYN-HI-001) in the treatment of irritable bowel syndrome: a multicentre, randomised, double-blind, placebo-controlled clinical trial. Lancet Gastroenterol Hepatol. 2020;5(7):658-666. doi:10.1016/S2468-1253(20)30056-X
  5. Liang B, Xing D. The Current and Future Perspectives of Postbiotics. Probiotics Antimicrob Proteins. 2023;15(5):1626-1643. doi:10.1007/s12602-023-10045-x

Image by Gerd Altmann