Postbiotics Gain Attention in Functional Foods

At Natural Products Expo West, Justin Green, PhD, director of scientific affairs at EpiCor, discussed the growing interest in postbiotics and how they differ from more familiar microbiome ingredients such as probiotics.

Green explained that probiotics are live microorganisms—typically bacteria or yeast—that have been well characterized and shown to provide health benefits when consumed in sufficient amounts. Importantly, not all bacteria qualify as probiotics; specific strains must be scientifically demonstrated to support health. Historically, the prevailing assumption in microbiome science was that these microbes needed to be alive to exert beneficial effects, largely because the human gut is home to a complex ecosystem of living microorganisms that help digest food and produce metabolites beneficial to the host.

Postbiotics, by contrast, consist of inactivated or non-living microbes. Although they originate from the same types of microorganisms used in probiotics, they are rendered inactive through processes such as heat treatment or pasteurization. For many years, researchers believed this inactivation would eliminate potential benefits, since the organisms could no longer colonize the gut.

However, Green noted that scientific observations began to challenge this assumption. In some studies designed to compare live probiotics with heat-killed controls, researchers occasionally observed that the non-living microbes still produced measurable health effects—and in some cases even greater benefits than their live counterparts. These findings suggested that microbial components or metabolites themselves may interact with the body in meaningful ways.

According to Green, postbiotics may exert their effects through interactions with the gut lining and immune system rather than by establishing colonies in the gastrointestinal tract. Microbial cell components and metabolites can signal physiological responses, helping the body regulate immune activity or maintain microbial balance.

Using EpiCor’s yeast-derived postbiotic ingredient, Green explained that certain postbiotic signals may help place the immune system in a heightened state of readiness while moderating inflammatory responses. As microbiome research continues to evolve, postbiotics are emerging as an additional category within the broader microbiome-focused nutrition market.

A transcript of his conversation can be found below.

Nicholas Saraceno: Given the value of postbiotics, obviously, they’re inanimate objects. What kind of factors are driving formulators to consider implementing them for functional food, beverages, and supplements?

Justin Green: Well, one is that consumers are interested in it. There's kind of this paradox of nutritional consumers, where they want to have the hottest trend, both in terms of that’s what their friends are doing, and in terms of the hottest science. Of course, they want the best science, the hottest science, but they also want something that's ancient, something that kind of predates science. And postbiotics really comes out of fermentation.

A fermented food, it's not as well characterized as a postbiotic, but it has dead microbes in there. You're really harnessing this old knowledge that fermented food is going to be good for you with postbiotics. You have this consumer awareness—I'm not going to say it's anywhere near as well-known as probiotics, and it's a new term. Part of that is the lure, but part of that is a challenge, where we need to educate people on postbiotics. But there is also some benefit to the formulators themselves that the consumers probably don't care so much about. And one of them is that, because they're killed, because the last step of making it is essentially a pasteurization step, and it still works, that means, if you pasteurize it again, it's also going to stay and it opens up the formulations that a biotic can be in. So probiotics can only be in formulations that are not going to have this harsh processing that you essentially need to keep food safe. And so postbiotics can ride the coattails of probiotics, both in terms of sounding the same, it works in the gut, but at the same time, not be much more stable than a lot of different formulations that are going to have.

Saraceno: Oh okay, interesting. You got into a lot of the benefits of both biotics. Obviously, it's very well positioned for the gut and to support immune health. Could you maybe get into, when it comes to the EpiCor version of the postbiotic, what kind of research or mechanism of action kind of underpin its role in that immune support/immune health, kind of dynamic?

Green: First of all, when you have that definition, that it has to give a health benefit, EpiCor is actually older than the term postbiotic. Just very quickly, what Epicor is: the microbe is baker's yeast. So it's a type of yeast that's used to make bread, Saccharomyces cerevisiae. It's the same species used to make beer and wine. That's brewer’s yeast. We're making use of baker's yeast, but what's important is how we ferment it. We ferment it in a specialized way, specifically for good health. That has been studied long before than the word postbiotic came out.

We already know that it's good for health. We have clinical trials that have shown that, it's just that we thought of it as being a fermentate. We called it a fermentate, a product of fermentation. Now the word postbiotic has come out. It's what EpiCor is, exactly, and so we have that. We're kind of doing it backwards. Instead of developing the ingredient. Oh, we need a new postbiotic. Oh, we haven't. Now we have to prove that it's good for you.

We already knew it was good for you, and now we're calling it a postbiotic. And through that, we have over a dozen other studies on EpiCor, both clinical studies that show, compared to placebo, that EpiCor does help people's immune system, both in terms of cold and flu incidence, and in terms of allergies, as well as a clinical study that shows that it's good for your gut and helps modulate your microbiome in beneficial ways.

We also have model studies that can get down to how it's happening. So we can see that certain immune biomarkers are stimulated, and we can see that the microbiome is being stimulated as well. We already have that science that shows that it's good for you, because now we're kind of figuring out why it's good for you and how it's good for you.

The two keys are the microbes and the gut. It’s an immune supplement. People might not think that their gut is connected to their immunity, but that's another thing that is also a big deal now, is realizing that the health of our gut is going to inform the rest of our bodies.

Saraceno: They always talk about the gut-brain axis. Obviously, gut-immune, might be less prominent.

Green: Now, people probably think of their challenges out there is coming from the air, coming from the surfaces that we touch. But you have to realize that we evolved long before we were humans to deal with dirty food.

Saraceno: That’s very true.

Green: And so actually, if you counted up all of our immune cells, 70% of them are our immune cells that are in the epithelium of our gut, that line our gut. So 70% of our immune system, essentially, is worried about our gut. And there are good reasons for that. Again, you have things that you're eating that you're putting into your body.

It also has to be very subtle. If there's something foreign in our blood or in our lungs, you’ve just got to get rid of it. If there's something foreign in our gut, it means you just ate something. And so it has to have a different sort of response. And one of the issues that people have with their gut can be inflammation.

Having a nice, balanced immune system is going to keep your gut from having that inflammation when it doesn't need to have it, potentially keep your gut healthier. It goes the other way around, a nice, healthy gut. I was talking about how the microbiome digests food, and it gives us these nice metabolites. Those metabolites are feeding those immune cells that are widening our gut, super-efficient, nice, healthy food that's happening right there. It doesn't have to get it from our blood to have it right from the digestion.

A nice, healthy gut is going to help our immunity. And that will be a cycle. We can keep both of them balanced and strong, they're going to help each other. But when things go wrong, it's going to be the other way around, where, if something goes wrong, this balanced gut is going to mess up our immunity, put it under stress, not feed it well enough, and then an immune system that's not working correctly, it's not going to be that good gatekeeper keeping the bad stuff out of our microbiome. It really can be a bad cycle. You want to keep the cycle positive going in the right direction.