In order to maintain health and a balanced gut microbiome, it’s important and necessary to implement probiotics in the form of dietary supplements or through consumption of probiotic foods, such as yogurt, kefir, sauerkraut, kimchi, kombucha and pickles. In recent times the need for implementing paraprobiotics has also been mentioned in the context of microbiome wellness.

What are paraprobiotics?

Non-viable probiotics are known under many different names, such as ghost probiotics or inactivated probiotics. Their newest name, first coined in 2011, is paraprobiotics. The term paraprobiotics refers to inactivated (non-viable) microbial cells and their cell parts which contribute to the consumer’s health.


Only ten or so bacterial species are used as paraprobiotics. These include Bifidobacterium lactis Bb12, Bifidobacterium longum, Lactobacillus gasseri OLL2716, Saccharomyces cerevisiae, Lactobacillus brevis SBC8803 and Lactobacillus delbrueckii, subspecies bulgaricus OLL1073R-1. They are mostly administered orally, seldom topically.


Paraprobiotics are considered to be equally as effective as probiotics themselves. So far, research has demonstrated the beneficial effects of paraprobiotics on the organism, owing to multiple mechanisms. One of them is immunomodulation and the other is increased adhesion to intestinal cells, which leads to pathogen inhibition. Additionally, although paraprobiotics are dead cells, they excrete metabolites that contribute to homeostasis.

The particular metabolites excreted by paraprobiotics are proteins, peptides, polysaccharides (including beta-glucans), DNA fragments originating from Lactobacillus sp. bacteria and lipoteichoic acid which stimulates the immune system and prevents an overly intense monocytic response.

Despite the mechanisms that have been uncovered, the details of those mechanisms and interactions with the gastrointestinal tract, respiratory and other systems are yet to be discovered. Unlike probiotic mechanisms, paraprobiotic mechanisms are easier to hypothesise.

How paraprobiotics are made

Paraprobiotics originate from probiotics when they are treated by heat, exposed to increased pressure, sonication and radioactive or ultraviolet radiation.

The benefits of paraprobiotics

The primary benefit of paraprobiotics is that they can be used by all populations, whereas the same cannot be said about probiotics. For example, immunocompromised patients, patients with a damaged intestinal barrier, septic patients and premature babies shouldn’t ingest probiotics.

The addition of paraprobiotics to food lends itself to numerous other benefits, such as reduced or non-existent interactions with other food components, which allows for a longer shelf life, as well as an increased ability to process food, given the fact that paraprobiotics are resistant to thermic processing, and the simplicity of their storage and transport. Furthermore, paraprobiotics cannot transfer antibiotic resistance genes.

Given the fact that paraprobiotics are a non-viable life form, there is no bacterial proliferation, which allows the administration of a strictly controlled amount of bacteria in order to achieve a more successful, more precise and more reproducible therapeutical effect. All this is to say that paraprobiotics have the same effect as probiotics, but without the side effects.

Health improvement

Paraprobiotics can be included in the treatment of diarrhoea, colitis, alcohol-related liver disease, respiratory illnesses, intestinal lesions, visceral pain and inflammation and for the purpose of modulation of the immune system, gut microbiota and bacterial translocation. They have even been proven to reduce lactose intolerance, cavities and aging. Therefore it can be stated that paraprobiotics have anti-inflammatory, immunomodulatory, antiproliferative and antioxidative properties.

Parabiotics vs. postbiotics

Some may confound the term “paraprobiotics” with “postbiotics”, however, these terms are not synonyms. Unlike the aforementioned paraprobiotics, postbiotics refer strictly to metabolites, liquid factors and cell-free supernatant (CFS), a liquid containing metabolites formed during bacterial growth as well as the residual nutrients from the medium used. In simpler terms, postbiotics refer to what is formed during the in vitro proliferation of bacteria which are later used as probiotics.



1. Almada C et al. Paraprobiotics: Evidences on their ability to modify biological responses, inactivation methods and perspectives on their application in foods. Trends in Food Science & Technology, 2016, 58.

2. Taverniti V, Guglielmetti S. The immunomodulatory properties of probiotic microorganisms beyond their viability (ghost probiotics: proposal of paraprobiotic concept). Genes Nutr, 2011, 6, 261–274.

3. Martyniak A et al. Prebiotics, Probiotics, Synbiotics, Paraprobiotics and Postbiotic Compounds in IBD. Biomolecules, 2021, 11(12), 1903.


Photography source

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