Postbiotic: Product made by intestinal bacteria that affects a range of physiological processes.



Dietary fiber can be broken down and fermented in the colon by bacteria into a number of products, which we call postbiotics. Postbiotics include acetate, butyrate, and propionate, which fall under the category of short-chain fatty acids. The production of short-chain fatty acids is determined by several factors, including the numbers and types of bacteria present in the gut and the specific source of fiber (3,7).

Scientific research has focused mainly on butyrate, which is an important energy source for the cells that line the gut. The major microbial groups that produce butyrate are Clostridia, Eubacteria, and Roseburia (8). Notably, researchers have found the number and variety of butyrate-producing bacteria to be significantly reduced in people with a variety of disorders (9,10). 

The effects of short-chain fatty acids extend beyond the gastrointestinal tract. Propionate and acetate are carried in the bloodstream to a variety of different organs where they are used for important metabolic processes (11,12).

Short-chain fatty acids are among the most important products of the gut microbiota. They affect a range of physiological processes including energy utilization, communication between human and microbial cells, and control of acid levels in the colon. These effects have consequences on the composition of the gut microbiome and general colon health.

Most of the beneficial activities of bacteria are associated to their metabolites (postbiotics). The great thing about postbiotics is that you get all the benefits without the bacteria!

The main benefits of postbiotics are:

  • Safer: no harmful bacterial components,
  • Host Reproducibility: no need for bacterial growth or colonization,
  • Efficacy: higher concentration of active components.

Courtesy of CSIRO.


  1. Blaser, M. J. Who are we? Indigenous microbes and the ecology of human diseases. EMBO Rep.7, 956–960 (2006). Article.
  2. Strachan, D. P. Hay fever, hygiene, and household size. BMJ 299, 1259–1260 (1989). PDF.
  3. Roberfroid, M. Prebiotics: the concept revisited. J. Nutr.137, 830S–7S (2007). PDF.
  4. Strate, L. L. Lifestyle factors and the course of diverticular disease. Dig Dis 30, 35–45 (2012). Abstract.
  5. Trumbo, P., Schlicker, S., Yates, A. A., Poos, M.Food and Nutrition Board of the Institute of Medicine, The National Academies. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein and amino acids. J Am Diet Assoc 102, 1621–1630 (2002). Abstract.
  6. Mariat, D. et al. The Firmicutes/Bacteroidetes ratio of the human microbiota changes with age. BMC Microbiol.9, 123 (2009). Article.
  7. Cook, S. I. & Sellin, J. H. Review article: short chain fatty acids in health and disease. Alimentary Pharmacology & Therapeutics 12, 499–507 (1998). Abstract.
  8. Nicholson, J. K. et al. Host-gut microbiota metabolic interactions. Science 336, 1262–1267 (2012). Abstract.
  9. Frank, D. N. et al. Molecular-phylogenetic characterization of microbial community imbalances in human inflammatory bowel diseases. Proc. Natl. Acad. Sci. U.S.A.104, 13780–13785 (2007). Article.
  10. Wang, T. et al. Structural segregation of gut microbiota between colorectal cancer patients and healthy volunteers. ISME J 6, 320–329 (2012). Article.
  11. Wong, J. M. W., de Souza, R., Kendall, C. W. C., Emam, A. & Jenkins, D. J. A. Colonic health: fermentation and short chain fatty acids. J. Clin. Gastroenterol.40, 235–243 (2006). Abstract.
  12. Samuel, B. S. et al. Effects of the gut microbiota on host adiposity are modulated by the short-chain fatty-acid binding G protein-coupled receptor, Gpr41. Proceedings of the National Academy of Sciences 105, 16767–16772 (2008). Article.