What Are Postbiotics? Benefits and What to Know

Gut health conversations often focus on probiotics and prebiotics, but another important piece of the puzzle is gaining attention: postbiotics.

Researchers are increasingly interested in postbiotics because they may provide some of the benefits associated with probiotics while being more stable and easier to standardize in supplements and foods 1 2. 

Let’s take a closer look at postbiotics, including what they are, how they differ from probiotics, and why researchers are increasingly interested in their potential health effects.

What Are Postbiotics?

Postbiotics are preparations of inactive (non-living) microbes or microbial components, like cell walls, that benefit your health. To be considered effective, a postbiotic must contain inactive microbial cells or their components, sometimes along with substances they produce (metabolites), that help create measurable health benefits 2. Unlike probiotics, which are live microorganisms, postbiotics are non-living substances that may still support digestive and immune health. 

Postbiotics can include non-living microorganisms, including inactivated probiotic and non-probiotic bacteria, as well as yeasts and fungi. They may also contain microbial cell fragments and other compounds present in postbiotic preparations, such as short-chain fatty acids, enzymes, vitamins, lipids, organic acids, and peptides 2 3.

Unlike probiotics, postbiotics are not living organisms. This has led researchers to investigate whether they may offer some practical advantages, such as improved shelf stability and less sensitivity to stomach acid or temperature changes.

What Are Examples of Postbiotic Preparations?

Postbiotic preparations are derived from inactivated (non-living) microorganisms and/or their components. Examples include heat-inactivated preparations of Lactobacillus, Bifidobacterium, and Bacillus species 4. 

Some postbiotic preparations may also contain compounds produced during microbial growth or fermentation. These are not considered postbiotics on their own but may be present in postbiotic preparations, including substances such as vitamins and short-chain fatty acids.

The short-chain fatty acid butyrate has received significant attention because it serves as a major energy source for cells lining the colon. Research suggests it may help support intestinal barrier integrity and regulate inflammation in the gut 5 6. 

Other examples of postbiotic metabolites include: 

• Acetate and propionate (short-chain fatty acids) 
• Bacteriocins (antimicrobial substances made by bacteria)
• Enzymes
• Peptides

Together, these compounds may help explain why postbiotics are being studied for their potential effects on gut barrier function, regulation of inflammation, and overall digestive health.

Where Can You Find Postbiotics?

Fermented foods may naturally contain inactivated microbial cells and components that are also found in postbiotic preparations 2 4. Because postbiotic preparations may include inactivated microorganisms, fermented foods do not need to be raw or unpasteurized to contain postbiotic-related components.

Fermented foods with postbiotic benefits include:

• Yogurt and fermented milks
• Kefir
• Kimchi
• Sauerkraut
• Miso
• Tempeh
• Fermented pickles and vegetables

For most people, focusing on overall dietary diversity and fiber intake is likely more important than trying to target a single postbiotic compound.

Comparing Postbiotics, Prebiotics, & Probiotics

Prebiotics, probiotics, and postbiotics are all connected, but each serves a different function in the gut microbiome.

Prebiotics are types of fiber and plant compounds that feed specific, beneficial gut bacteria. Foods like garlic, onions, oats, bananas, and legumes contain prebiotics that help nourish the microbes already living in your gut.

Probiotics are live microorganisms found in fermented foods and supplements that provide a health benefit. Common probiotic-rich foods include yogurt, kefir, kimchi, sauerkraut, and miso. Probiotic supplements typically contain well-studied probiotic microbes such as Bifidobacterium and Lactobacillus. These microbes may help support microbial balance, digestion, and immune function.

Postbiotics are preparations of inactivated (non-living) microorganisms and/or their components that may still benefit health. These preparations must contain inactive microbial cells or their components and demonstrate a measurable health benefit. Postbiotics are not necessarily better than probiotics; they simply work differently. Because they are not living organisms, postbiotics may be more stable during manufacturing and storage and less sensitive to heat, oxygen, and stomach acid. However, probiotics may still provide unique benefits that isolated postbiotic compounds cannot fully replicate.

Rather than competing, prebiotics, probiotics, and postbiotics often work together. Prebiotics feed beneficial microbes, probiotics help support the microbiome directly, and postbiotics are preparations of inactivated microorganisms and/or their components that may help support digestive and immune health.

Here’s a quick guide plus the various foods you can find all of the “-biotics” in:

It’s important to mention that any fermented foods can contain both probiotics and postbiotics. However, not all fermented foods still contain live probiotics by the time you eat them. 

Benefits of Postbiotics

Research on postbiotics is still developing, but early studies suggest they may support several aspects related to digestive, immune, and skin health.

Some potential benefits associated with postbiotics include:

• Supporting the gut lining 7
• Helping maintain a balanced microbiome 7
• Influencing immune function 7
• Supporting digestive comfort
• Producing anti-inflammatory effects 7
• Helping gut infections, like H. pylori 8 9
• Improving irritable bowel syndrome (IBS) symptoms 10
• Improved acne and skin health 11

One reason researchers are interested in postbiotics is that they are inactive. Because of this, they provide benefits that probiotics don’t, such as increased stability, shelf life, and even improved safety. 

While probiotics are generally considered safe for the general population, some people, such as those with compromised immune systems, may be at risk from live probiotic bacteria. Because postbiotics do not contain live microorganisms, researchers are investigating whether they may offer certain safety or stability advantages in some populations 2. 

Postbiotics and Gut Health

Postbiotics appear to play an important role in communication between gut microbes and the human body. Unlike probiotics, which are live microorganisms, postbiotics are preparations of inactivated microbes and their structural components that may still exert biological effects in the gut.

Research suggests certain postbiotics may help support intestinal barrier integrity, influence immune signaling, and regulate inflammatory pathways involved in digestive health 12 13. Some studies also suggest postbiotics may help create an intestinal environment that supports beneficial microbes while discouraging the growth of potentially harmful bacteria.

For example, emerging research has explored the potential role of postbiotics in conditions such as irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and Helicobacter pylori infection, although more high-quality human research is still needed to better understand their clinical applications 7 10 14 15.

It’s important to note that compounds like butyrate and other short-chain fatty acids are not considered postbiotics on their own under the current International Scientific Association for Probiotics and Prebiotics (ISAPP) definition. However, these metabolites may still be present within some postbiotic preparations and are thought to contribute to some of their potential health effects.

Downsides of Postbiotics

Although postbiotics are promising, there are still important limitations to the research.

One challenge is that the term “postbiotics” was only recently defined by the ISAPP, which means that much of the research on postbiotics includes compounds that aren’t technically considered postbiotics under the current definition.

There is also limited long-term human research on many postbiotic supplements currently being marketed. Because postbiotics are a newer area of research, we don’t fully understand the mechanisms behind how they work 7. In some cases, marketing claims may move faster than the available evidence.

Other potential downsides include:

• Lack of standardized dosing
• Variation between products
• Limited regulation of supplements

For now, most experts would likely consider postbiotics an emerging area of gut health research rather than a fully established therapy.

Should You Take a Postbiotic Supplement?

Currently, there are a small handful of high-quality postbiotics on the market, including EpiCor® and Pylopass. As interest in postbiotics grows, you will likely see an increasing number of supplements that contain postbiotics like these. Aside from finding a supplement that contains postbiotics, a quick and tasty way to get in postbiotics daily may simply be adding fermented foods to your diet.

And of course, supporting your gut health through diet and lifestyle should always come before layering in any supplements. This includes:

• Eating more fiber-rich, nutrient-dense foods
• Including fermented foods regularly
• Managing stress
• Sleeping adequately
• Getting regular physical activity, like Zone 2 Training
• Addressing underlying digestive issues

Postbiotic supplements may become more clinically useful as research develops, but current evidence still favors a foundational, food-first approach for most individuals.

Why Is There So Much Confusion Around Postbiotics?

Part of the confusion around postbiotics stems from the term’s evolution over time and its relative newness in clinical nutrition and microbiome research. Earlier definitions often described postbiotics broadly as “metabolic byproducts” of probiotic bacteria, leading to the inclusion of compounds like short-chain fatty acids, vitamins, and other fermentation products in many online explanations.

However, the current consensus definition from the International Scientific Association for Probiotics and Prebiotics is more specific. It defines postbiotics as preparations of inactivated (non-living) microorganisms and/or their components that confer a health benefit on the host 2. Under this definition, isolated microbial metabolites such as butyrate or vitamins are not considered postbiotics on their own, although they may be present within postbiotic preparations.

This shift in definition means that much of the existing literature and consumer-facing content uses a broader, outdated interpretation of the term. As a result, readers may encounter conflicting descriptions depending on whether the source is using the older metabolite-focused framework or the updated ISAPP consensus definition.

Postbiotics FAQs 

Are postbiotics better than probiotics?

Not necessarily. Probiotics are live microbes, while postbiotics are inactive (heat-treated) microbes. Each may have different advantages depending on the individual and the health goal.

How to get postbiotics naturally?

You can get natural postbiotics from fermented foods like yogurt, kefir, kimchi, and sauerkraut.

What are the downsides of postbiotics?

Potential downsides include limited human research, lack of standardized formulations, and uncertainty around which compounds work best for different conditions.

Do postbiotics help with inflammation?

Some postbiotics may help regulate inflammatory responses in the gut. However, more high-quality human studies are needed.

Can you take probiotics and postbiotics together?

Yes. As research on postbiotics continues, it is likely that you will begin to see more products that combine prebiotics, probiotics, and postbiotics. 

The Bottom Line on Postbiotics

Postbiotics are an emerging area of gut health research that may help support the gut lining, immune function, and microbial balance. While early findings are promising, much of the research is still developing, and postbiotics are best viewed as one piece of a broader gut health strategy.

For most people, supporting the microbiome through fiber-rich foods, fermented foods, and targeted digestive support as needed is likely to have the greatest impact.

If you’re struggling with ongoing digestive symptoms or want a more personalized approach to improving gut health, the team at our virtual clinic can help. You can also learn more about Dr. Ruscio’s Triple Therapy Probiotic, which combines three evidence-based probiotic categories designed to support overall microbiome health.

Dr. Michael Ruscio is a DC, natural health provider, researcher, and clinician. He serves as an Adjunct Professor at the University of Bridgeport and has published numerous papers in scientific journals as well as the book Healthy Gut, Healthy You. He also founded the Ruscio Institute of Functional Health, where he helps patients with a wide range of GI conditions and serves as the Head of Research.