Just when you thought you were across the gut health terminology, there’s another ‘biotic’ to add to the vocab. You’ve probably heard of prebiotics and probiotics, but what about postbiotics? Although research is currently limited, postbiotics are thought to play a role in supporting our immune system among other beneficial effects.
Postbiotics have gained significant interest in the literature in recent years, with more than 87% of total scientific publications on this topic being carried out in the past three years alone (1).
So, what are postbiotics?
According to a recent review, postbiotics are defined as “any substance released by or produced through the metabolic activity of the microorganism, which exerts a beneficial effect on the host, directly or indirectly”(2). Not to be confused with probiotics or prebiotics, postbiotics are the waste product of the fermentation process.
- Probiotics are the live bacteria that are naturally found in our gut and in some foods. Sources of probiotics include fermented foods such as kombucha, yoghurt with live cultures, kefir, kimchi and sauerkraut. Strains of probiotics are also now commonly added to breakfast cereals such as muesli.
- Prebiotics are soluble fibres and resistant starches that act as fuel for our good gut bacteria. Sources include whole grains, legumes, unripe bananas and some vegetables like asparagus, onion and garlic.
- Postbiotics are the waste product of the fermentation process in our gut which may offer physiological benefits. In basic terms, probiotics feed on prebiotics which produce postbiotics.
Examples of postbiotics include short chain fatty acids, such as butyrate, propionate and acetate, amino acids, enzymes, cell wall components and other metabolic by-products.
Any substance released by or produced through the metabolic activity of the microorganism, which exerts a beneficial effect on the host, directly or indirectly
What does the evidence say?
Although research on postbiotics is still emerging, evidence suggests they may play a role in supporting our immune system and may have anti-inflammatory and antioxidant effects (2).
Short chain fatty acids (SCFA) butyrate, propionate and acetate are important for maintaining a healthy colon as they are thought to have anti-inflammatory effects on the lining of the bowel. SCFA may also play a role in regulating the immune system and offers protection from development of immune disorders, as well as regulation of blood glucose levels and appetite control (3-5).
While you can purchase postbiotics in supplement form, research on their use and the claimed benefits is limited. As postbiotics are produced from the fermentation process by your gut bacteria, you can naturally boost the production of postbiotics by eating a variety of pre-and probiotic containing foods such as whole grains, legumes and fermented foods. Read more about gut health in this recent hot topic on the microbiome by APD Nicole Dynan.
GLNC recommends enjoying 48g (3 serves) of whole grain foods daily and 100g of legumes 2-3 times per week, as part of a healthy diet rich in fruits, vegetables, nuts, seeds, dairy and lean meat to achieve a healthy gut microbiome.
Evidence suggests postbiotics may play a role in supporting our immune system and may have anti-inflammatory and antioxidant effects
The bottom line
Our understanding of how our gut bugs affect our health is rapidly advancing and evolving and there is so much about the gut microbiome that we are yet to discover, including the role of postbiotics. What is clear is the value of consuming a variety of plant-based foods, like whole grains and legumes to achieve a diverse gut microbiome for overall health.
References
- Cabello-Olmo, M.; Araña, M.; Urtasun, R.; Encio, I.J.; Barajas, M. Role of Postbiotics in Diabetes Mellitus: Current Knowledge and Future Perspectives. Foods 2021, 10, doi:10.3390/foods10071590.
- Żółkiewicz, J.; Marzec, A.; Ruszczyński, M.; Feleszko, W. Postbiotics-A Step Beyond Pre- and Probiotics. Nutrients 2020, 12, doi:10.3390/nu12082189.
- Wegh, C.A.M.; Geerlings, S.Y.; Knol, J.; Roeselers, G.; Belzer, C. Postbiotics and Their Potential Applications in Early Life Nutrition and Beyond. International Journal of Molecular Sciences 2019, 20, doi:10.3390/ijms20194673.
- Morrison, D.J.; Preston, T. Formation of short chain fatty acids by the gut microbiota and their impact on human metabolism. Gut Microbes 2016, 7, 189-200, doi:10.1080/19490976.2015.1134082.
- Blaak, E.E.; Canfora, E.E.; Theis, S.; Frost, G.; Groen, A.K.; Mithieux, G.; Nauta, A.; Scott, K.; Stahl, B.; van Harsselaar, J., et al. Short chain fatty acids in human gut and metabolic health. Benef Microbes 2020, 11, 411-455, doi:10.3920/bm2020.0057.