Postbiotics are becoming increasingly common in research and nutritional formulations, and they are intriguing.
But what lies behind this little-known term?
Far from being a mere trend, they respond to real scientific and industrial challenges, while opening up new perspectives for health.
What is a postbiotic?
The scientific definition from ISAPP
According to ISAPP, postbiotics are:
“preparations based on inanimate microorganisms and/or their components that confer a health benefit on the host”
(Nature Reviews Gastroenterology & Hepatology, 2021).
What exactly does this definition mean?
Postbiotics are “deactivated” bacteria (killed by heat, pressure, or other processes), and/or their cellular components, and/or their metabolites that have health-promoting properties.
Composition: what are postbiotics made of?
Postbiotics are complex preparations whose composition depends on the bacterial strains and processes used. There are generally three main categories of components:
- Inactivated intact bacterial cells (killed by heat, pressure, or other physical or chemical processes)
- Bacterial cell fragments (cell walls, membranes, intracellular components)
- Metabolites: substances produced by bacteria during their growth (short-chain fatty acids, peptides, enzymes, vitamins, exopolysaccharides, etc.)
Important: To be considered postbiotic, the product must contain microbial cell components, not just purified metabolites alone.
How are postbiotics produced?
1. Fermentation
Bacterial strains are cultured under controlled conditions of temperature, pH, oxygen, and medium composition.
This step allows the production of metabolites of interest.
2. Controlled inactivation
Inactivation aims to render the bacteria inanimate while preserving their structure and components.
Various methods are possible:
- Heat treatment
- Pressure
- Irradiation
- Chemical treatment
3. Quality control
Each batch of postbiotics must be rigorously characterized:
- Identification of the strain
- Verification of the absence (or negligible amount) of viable bacteria
- Quantification of active components
Postbiotics and probiotics: what are the fundamental differences?
The main distinction seems obvious—living versus non-living—but the implications are numerous and nuanced.
Biological differences
Probiotics: These are living microorganisms that must survive passage through the stomach, temporarily colonize the intestine, and exert their effects through their metabolic activity and interaction with the existing microbiota.
Postbiotics: They do not need to be alive to be effective. Their effect comes from their molecular structure or from bioactive compounds that are already formed. They act more like biochemical messengers or modulators of the immune system.
Practical differences
| Aspect | Probiotics | Postbiotics |
| Stability | Living ingredients, therefore sensitive to several factors | Generally more stable |
| Characterization | Perfectly identified and standardized | Exact composition and standardization sometimes difficult |
| Formulation | Significant technical constraints to ensure viability | More flexible: Fewer constraints in terms of incompatibility with other active ingredients and galenics |
| Quality control | CFU count, viability | No consensus on analytical methods |
Important:
- The effects of a live probiotic cannot automatically be attributed to its inactivated version
- Each postbiotic requires its own studies
What does scientific research say?
A field still in its infancy
It is important to note that research on postbiotics is still in its early stages. While some studies are promising, the level of evidence remains, for now, well below that of probiotics.
Mechanisms of action of postbiotics
Current scientific hypotheses suggest that postbiotics may act through several mechanisms:
Action on existing microbiota
Metabolites such as short-chain fatty acids (butyrate, acetate, propionate) nourish intestinal cells and influence other bacteria.
Strengthening of the intestinal barrier
- Some components promote mucus production.
- Others may strengthen the junctions between intestinal cells and reduce permeability.
Modulation of the immune system
- Certain fragments of bacterial walls stimulate specific receptors (such as Toll-like receptors) present on immune cells
- This stimulation positively modulates the inflammatory response.
Systemic effects
- Some are capable of producing neurotransmitters that influence stress and cognition.
- Other compounds may have anti-inflammatory effects beyond the intestine.
However, these mechanisms are still largely under study and vary considerably depending on the type of postbiotic considered.
Applications explored in research
Current areas of investigation include:
- Functional bowel disorders
- Support after antibiotic therapy
- Chronic inflammatory bowel diseases (with preliminary results, but not yet conclusive)
- Modulation of the immune response
- Prevention of respiratory infections (data still limited)
- Stress, anxiety
- Sleep quality
- Cognitive function
Other avenues
- Metabolic health
- Skin health
- Athletic performance
Although most of these applications are in the exploratory research stage, there are clinical studies indicating the effect of postbiotics on human health.
Postbiotics: the future of biotics?
Postbiotics are not simply a variant of probiotics: they constitute a category in their own right, with their own mechanisms of action.
Their strength? They combine clinically proven efficacy with considerable technological advantages. These characteristics make them the ingredients of choice for developing high-performance dietary supplements that are less sensitive to industrialization constraints.
Rather than replacing probiotics, postbiotics expand the possibilities for action on the microbiota and health. Intensified academic and industrial research is gradually paving the way for exploiting their full potential across multiple indications.
One thing is certain: postbiotics are only beginning to reveal their full potential.
Integrate postbiotics into your future innovations
Are you developing innovative dietary supplements?
Postbiotics represent a major opportunity to differentiate yourself in the dietary supplement market. But their development requires specialized expertise.
Let’s talk about your project: contact@exden.fr
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