According to ISAPP definition, a postbiotic is “a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host”¹. For instance, a postbiotic can contain intact inanimate microorganism cells, fragments or structures of inactivated microorganisms and compounds from culture medium or produced by microorganisms during fermentation.

Postbiotics do not come from a chemical synthesis for their manufacturing process. The first step is a biological process, the grow of microorganisms into a culture medium, and the second one is to inactivate them by a thermal or mechanical treatment.

Probiotics are “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host“² whereas postbiotics are “a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host“¹. In a nutshell, both have beneficial health effects, but probiotics are live bacteria while postbiotics are non-living bacteria and/or fragments or metabolites of theirs.

Postbiotics are mostly used in the medical field; their positive impact has been demonstrated in different situations such as dysbiosis and irritable bowel syndrome. But postbiotics could also have nutritional benefits. For example, they could be beneficial in the management of acute and antibiotic associated diarrhea

Because they have a better safety profile, postbiotics are suitable for both adults and children. For instance, they are not expected to pass into the bloodstream through the intestinal barrier, so they are unlikely to cause bacteriemia or fungaemia. Moreover, postbiotics cannot cause antibiotic resistance.

Postbiotics can be found in functional foods and beverages, food supplements and drugs.

Prebiotics and probiotics are totally compatible. Prebiotics help feed the probiotics: they act in synergy. In principle, postbiotics are sufficient on their own, but to date, there are no contraindications to taking pre, pro and postbiotics simultaneously. If you have any doubts, ask a health care professional for advice!

The fact that non-living microorganisms can have beneficial effects on health has been known in the scientific world for over 40 years. However, the strict definition of the term “postbiotics” was still under debate until 2021. This year, the International Scientific Association of Probiotics and Prebiotics (ISAPP), has clarified the definition of postbiotics as following: “A preparation of inanimate microorganisms and/or their components that confers a health benefit on the host³“

Had your heard about probiotics 20 years ago? Probably not, because at the time, the concept was still emerging and only a few products existed on the consumer market. Well, it is the same for postbiotics today. Even if the concept is not new, the definition has just been clarified and will be used as a base for the development of new products in the next years.

Postbiotics have several modes of action to confer a beneficial effect on health. On the one hand, they interact directly with the gut microbiota. On the other hand, the postbiotics adhere to the gut cells and contribute, by so doing, to the protection of the intestinal barrier and the activation of the immune system.

Postbiotics have a positive impact on the microbiota, a protective role on the intestinal barrier and positive effects on both the metabolism and the immune system.

Because postbiotics contain inanimate cells, they have a better safety profile. For example, they are unlikely to cause antibiotic resistance nor bacteriemia and fungaemia. Moreover, their inanimate nature makes them very convenient. They are not sensitive to heat or oxygen which make it possible to get rid of the storage and stability concerns encountered with most of the probiotics.