What Are Postbiotics (& Why We Need Them)

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What Are Postbiotics?
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Many of us moms struggle with digestive issues. We’re busy, we’re eating on the run, and there’s barely even time to run to the bathroom on a good day! The tricky part is incorporating good eating habits while juggling all the things family life throws at us. It can be a circus sometimes! 

While eating healthy and focusing on whole foods is essential, supplements can also help you support your microbiome to digest all those healthy foods. That’s where prebiotics, probiotics, and postbiotics come in. 

Haven’t heard of POSTbiotics? Well, not to worry as we will dive into them in this article.

What Are Postbiotics? 

Postbiotics are the product of your gut bacteria digesting a prebiotic. They are technically a waste product of the bacteria. They include a variety of metabolites, including:

  • Short-chain fatty acids (SCFAs)
  • Lipopolysaccharides
  • Exopolysaccharides
  • Enzymes
  • Cell wall fragments
  • Bacterial lysates (mixture of bacterial pieces)
  • Cell-free supernatants (mixture of compounds made by bacteria and yeast)
  • Amino acids, vitamins, antimicrobial peptides, and more

These are known for their health-promoting effects, particularly for the digestive and immune systems.

They can be a shortcut for optimizing your digestive health. If your doctor agrees, you can intentionally include foods that promote postbiotics in your diet or consider adding a postbiotic supplement. 

Postbiotics vs. Prebiotics 

The difference between postbiotics and prebiotics is that we make postbiotics from prebiotics. Prebiotics are the fibers and starches that are naturally present in foods. 

The gut bacteria digest these fibers and starches and produce postbiotics, SCFAs, and other compounds. “Bacterial metabolites” is another name for them. 

The common SCFAs include butyrate, acetate, propionate, pentanoic, and hexanoic acid. Butyrate is the most important of the SCFAs. Research has shown this postbiotics can improve many aspects of gut health, which we’ll cover below. 

Postbiotics vs. Probiotics

The difference between postbiotics and probiotics is that probiotics are the actual live bacteria you can take in supplements (like the lactobacillus and bifidobacterium species). When taken as supplements, these living microorganisms produce beneficial effects in the host (you).

Probiotics may be combined with prebiotics in a supplement to increase the production of these important compounds. We call these combinations “synbiotics,” as they work synergistically.

Taking synbiotics may help in the production of postbiotics. It’s just that specific processes must take place to produce them. If conditions aren’t optimal in the digestive system, these processes may not work as efficiently. 

For that reason, it may be helpful to jump straight to the end product of probiotics digesting prebiotics, which is: postbiotic supplements. 

Health Benefits of Postbiotics 

Postbiotics are good for your overall health and wellbeing. However, some specific documented health benefits, especially the SCFA butyrate, include:

  • Lowering inflammation – Butyrate suppresses inflammation in the colon by reducing the inflammation-promoting cells and proteins. 
  • Repairing leaky gut A form of butyrate called tributyrin supports the formation of tight junctions in the gut lining to combat leaky gut.
  • Supporting the mucus layers of the gut – The body needs SCFAs to produce mucus in the intestines. They also affect the blood flow to the mucus layers of the colon, which supports digestive health. Without enough SCFAs, the mucus layers cannot maintain their thickness. 
  • Increasing the number of beneficial bacteria in the gut – Supplementation with SCFAs was shown to promote bacteroidetes in animal studies, which helps maintain a healthy weight.
  • Eliminating pathogens – Postbiotics have shown promise in protecting children against infectious diseases by improving the balance of the gut microbiome. 
  • Improving immune function – Some postbiotics, like butyrate, help to rein in an overactive immune response, while others help to increase the immune response. 
  • Lowering autoimmunity – In preventing an overly aggressive immune response, postbiotics may improve symptoms of autoimmune disease.
  • Improving allergies – Children with food allergies tend to have a deficiency in butyrate. Based on animal research, postbiotics, like SCFAs, may be a helpful treatment for food allergies
  • Protecting against cancer – Early research suggests postbiotics could suppress the growth of cancer cells, particularly in the gut. 

Without enough postbiotic compounds like butyrate in the body, a person may be more likely to develop immune or gut-related problems. 

Conditions that are associated with low butyrate levels include the following: 

  • Inflammatory bowel diseaseCrohn’s and ulcerative colitis, both autoimmune diseases
  • Irritable bowel syndromeIBS – both constipation-dominant and diarrhea-dominant
  • Colon cancer – preliminary studies suggest postbiotics may even help in the treatment
  • Type 1 diabetes – diets high in acetate or butyrate provided a high degree of protection from diabetes
  • Rheumatoid arthritisan autoimmune disease – rheumatoid arthritis (RA) patients and animal models of RA have lower levels of SCFAs compared to healthy controls
  • Obesity – due to an imbalance in the gut microbiota
  • Parkinson’s disease – the gut-brain connection
  • Allergies in children – skin allergies, asthma, food allergies, and seasonal/environmental allergies

These conditions are more likely because the SCFAs balance the immune system and protect against inflammation and damage to the tissues. 

So, how do we improve low butyrate levels? We can do it through food and supplementation.

Postbiotic Foods

As you may know from previous blog posts, I try to get as much nutrition from food as possible—before adding supplements. So, before you consider adding a postbiotic supplement, take a look at these dietary sources:

Resistant Starches 

Resistant starches are those that “resist” digestion and provide a food source for our gut bacteria:

  • Leftovers! – cooked and cooled potatoes, sweet potatoes, rice, oats, pasta (doesn’t have to be wheat), beans, legumes, other grains
  • Green (unripe) bananas – higher in starches and lower in sugars
  • Flours/meals: green banana flour, potato starch, Hi-Maize starch

These can be really easy to incorporate by making potato salad with cooled potatoes, adding cooked sweet potatoes to a salad, making gluten-free baked goods with potato starch, and just reheating leftovers. 


Pectin is a type of fiber that’s naturally present in certain fruits and vegetables, including:

  • Apples 
  • Oranges 
  • Lemons
  • Apricots
  • Carrots

Pectin has naturally gelling capabilities, which is why we use it to make jams and jellies. Most people tolerate it well, and, unlike the next couple of food components, it isn’t high in FODMAPs, or fibers that can aggravate IBS and other symptoms. 


Inulin is a type of fiber called a polysaccharide. It’s in a category of non-digestible carbohydrates called fructans. Be careful with inulin if you have issues with FODMAPs. Here are some foods containing inulin:

  • Artichokes 
  • Onions 
  • Garlic 
  • Asparagus 
  • Chicory root 

Another postbiotic-promoting food component is fructooligosaccharides, shortened to FOS. 

Fructooligosaccharides (FOS) 

Fructooligosaccharides (FOS) is a type of polysaccharide. They are made up of fructose chains strung together. Again, be careful with foods high in FOS if you have issues with FODMAPs:

  • Onions
  • Jerusalem artichokes
  • Leeks
  • Garlic
  • Asparagus

Foods rich in inulin and FOS are easy to include in soups. Here are a few ideas:

You can even make your own French Onion Soup Mix


Nut consumption increases the production of butyrate-producing bacteria in the gut.

Fermented Foods

Fermented foods contain probiotic bacteria that secrete postbiotics.

  • Miso – A fermented soybean paste made by fermenting soybeans with salt and koji (a fungus, Aspergillus oryzae). Some add other ingredients, like seaweed, grains (rice or barley), and seeds. Cooks will use miso in soups, sauces, and seasonings. 
  • Tempeh – A fermented soybean cake that’s a part of traditional Indonesian cuisine. They ferment it with the Rhizopus species of fungus, Rhizopus oligosporus or Rhizopus oryzae. It’s often marinated in brine or spices and then fried. It tastes great in soups, stir-frys, sandwiches, or alone with a chili paste.
  • Sauerkraut – Not just for Germans! Fermented cabbage is a traditional fermented food from several countries, including Poland, Russia, and Hungary.
  • Kimchi – A fermented cabbage dish from Korea. It takes traditional sauerkraut to the next level with other vegetables like radishes, spring onions, and spices like red pepper, garlic, and ginger. 
  • Kefir – A fermented milk made with kefir grains, including traditional dairy kefir, coconut milk kefir, or water kefir soda.
  • Kombucha This fermented tea drink originated in China and spread through Russia and Eastern Europe. The original version is made of black tea and sugar and fermented with a starter called a SCOBY – an acronym for Symbiotic Colony of Bacteria and Yeast.

Traditional cultures have used these postbiotic foods for centuries around the world. (Learn more in this post about the importance of traditional foods). However, some people have issues tolerating these foods. Some are on the high FODMAP list, and others are high-histamine foods.

Potential Side Effects

Getting postbiotics from food sources may cause some side effects. Examples include:

That’s where a supplement can be supportive. These supplements tend to be much easier to tolerate than dietary fiber if you have compromised gut health.

Postbiotic Supplements

Postbiotic supplements are a great way to bypass the digestive processes needed to create these important compounds. If you’ve been dealing with compromised digestion for a while, a postbiotic supplement may be a good way to calm inflammation. It can also help balance your immune system.

My favorite way to add postbiotics into my health regimen is to rotate in this postbiotic from Just Thrive. Not only does it contain postbiotics, but it also includes other immune-supporting ingredients, like zinc, selenium, and echinacea.

It’s also gluten-free and lactose-free, and it doesn’t have any fillers, stearates, or flow agents like silicon dioxide. The veggie caps are easy to swallow.

This article was medically reviewed by Madiha Saeed, MD, a board certified family physician. As always, this is not personal medical advice and we recommend that you talk with your doctor.

Have you tried a postbiotic supplement, particularly if you have issues with FODMAP foods? What was your experience? Share with us below!

Katie Wells Avatar

About Katie Wells

Katie Wells, CTNC, MCHC, Founder of Wellness Mama and Co-founder of Wellnesse, has a background in research, journalism, and nutrition. As a mom of six, she turned to research and took health into her own hands to find answers to her health problems. WellnessMama.com is the culmination of her thousands of hours of research and all posts are medically reviewed and verified by the Wellness Mama research team. Katie is also the author of the bestselling books The Wellness Mama Cookbook and The Wellness Mama 5-Step Lifestyle Detox.


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