Things you need to know about postbiotics | Updated: 2023-07-28
What are postbiotics?
In simple terms, postbiotics referto the metabolites of probiotics after processing, including the remains of dead probiotic cells and their metabolic byproducts.
In May 2021, the International Scientific Association for Probiotics and Prebiotics (ISAPP) defined a postbiotic as “a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host”. This definition requires postbiotics to include non-living bacteria, bacterial metabolites and/or components after bacterial lysis.
The main metabolites include extracellular polysaccharides, short-chain fatty acids, bacteriocins and organic acids. The main components of the bacteria are lipoteichoic acid, teichoic acid, peptidoglycan, derivative polypetides and cell surface proteins.
In February 2023, the first group standard for postbiotics in China, Probiotic Lactic Acid Bacteria Postbiotics, was officially released and implemented. Based on the current status of scientific research and industrial application, the definition and scope of postbiotics are being refined and expanded.
Source strains and safety assessment of postbiotics
The genetic background and biological characteristics of the source strains of postbiotics need to be clearly identified recognized as safe. Identification, health efficacy and safety evaluation should be conducted at the strains level. Postbiotics retain the same active bacterial components as live strains, and have high physiological activity even after high-temperature treatment and digestion in the gastrointestinal tract.
For the preparation of postbiotics, compositional analysis should be conducted to clarify the efficacy factors and potentially harmful substances that may be produced. Subsequently, toxicological, pharmacological and pharmacokinetic analyses are required to determine the safety, health efficacy and optimal intake of postbiotics. Currently, there is no consensus on the safety evaluation of postbiotics both at home and abroad, and further improvements are needed.
Health benefits of postbiotics
Enhance immunity
Postbiotics have anti-inflammatory and anti-allergic effects. For example, butyrate in postbiotics can reduce intestinal inflammation.

Regulate gut flora
Postbiotics contain antibacterial substances such as lactic acid and bacteriocins, which can promote a balanced gut microbiome.
Regulate metabolism
Postbiotics can play a role in combating metabolic disorders such as obesity, hypertension and cardiovascular diseases.
Strengthen epithelial barrier function
Postbiotics can protect the gastrointestinal mucosa. For example, Lactobacillus paracasei-derived postbiotics can maintain the integrity of the intestinal barrier.
Promote skin health and combat colorectal cancer
Currently, research on the health effects of postbiotics is mainly based on in vitro and animal experiments and further human clinical research is needed for verification.
Advantages of postbiotics
Postbiotics not only mimic the health-promoting effect of probiotics, but also have the following advantages:
1. Clear molecular composition.
2. Good safety profile, avoiding immune reactions and transfer of anti-resistant genes associated with live probiotics.
3. Stable quality with a long shelf life.
4. Convenient processing, unaffected by heating and pH, and allowing for co-administration with antibiotics.
5. Versatile product applications. Postbiotics can be used not only as a substitute for probiotics in processed foods such as dairy and beverages but also in products that are not suitable for adding probiotics to meet the needs of consumers.
Applications of postbiotics
On the one hand, postbiotics have great value in the food industry and can be used as food nutritional supplements or biological preservatives. On the other hand, postbiotics play a positive role in the treatment of certain diseases, and can be used to improve enteritis, relieve constipation, and provide relief from allergies, showing great application potential in the medical field.
Adding postbiotics to medicines and nutritional supplements may become a novel approach for adjunctive therapy of certain diseases.