When Worlds Collide: Gut-Immune Axis Gaining Attention as Daily Wellness and Immune Support Converge

Researchers, healthcare providers, and the dietary supplement formulators alike have long spoken of the value of the gut-brain axis, and rightfully so. As a bidirectional communication network that links the central nervous system with the enteric nervous system, it uses neural, hormonal, and immune pathways to help regulate a multitude of functions, including digestion.¹

However, another communication network—the gut-immune axis—is gaining popularity as we better understand the intricate relationship between the gut and our health. In fact, the gastrointestinal tract is involved in so much more than just digestion, it’s home to activity in which the immune system learns to differentiate between harmful and harmless stimuli.² So, how can dietary supplements stimulate and support the healthy functioning of this system?

Gut-Immune Axis Research Highlights the Gut’s Role in Immune Regulation

In a conversation with Nutritional Outlook at this year’s Natural Products Expo West, Justin Green, PhD, director of scientific affairs at EpiCor, described the gut as central to immune function.

“If you counted up all of our immune cells, 70% of our immune cells are in the epithelium of our gut,” he explains. “And there are good reasons for that. You have things that you're eating, that you're putting into your body.”

Green explains that when the immune system is in balance, there is less inflammation in the 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 lining our gut…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.”

However, the inverse is also true. A dysbiotic microbiome, for example, “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,” says Green. “It really can be a bad cycle. You want to keep the cycle positive going in the right direction.”

Looking even deeper, a review published in Cellular & Molecular Immunology³ notes that data shows a correlation between the progression of neurological disorders, gut dysbiosis, altered metabolite pools, and inflammation, further cementing how interconnected health is with the gut. “This leads to the hypothesis that neurological disorders may be induced by a gut-immune mechanism,” the authors write. “Aberrations in the gut microbial composition can lead to dysregulated immune signaling, increased neuroinflammation, and disruptions in blood‒brain barrier integrity, all of which can exacerbate neurological dysfunction. This growing body of evidence underscores the therapeutic potential of targeting the gut microbiota and immune pathways to develop novel interventions for neurological diseases.”

Immune Health Supplements Shift From Seasonal Use to Daily Wellness

From a general wellness perspective, there used to be a defined cold and flu season, a time where cooler fall and winter temperatures created the ideal conditions for viruses to spread. The COVID-19 pandemic has since disrupted this pattern⁴—infection surges are now occurring year-round, causing the immune health supplement category to evolve. This is occurring not only when consumers take these products, but when they incorporate them into their daily routines.

The shift in perspective from seasonal to year-round support may be conducive to a gut-immune approach since gut health is not a seasonal health benefit, and consumers are receptive to gut modulating products. EpiCor, for example, is a yeast fermentate of Saccharomyces cerevisiae (AKA baker’s yeast), which is a type of postbiotic.

“We have over a dozen studies on EpiCor, 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,” Green explains. “We also have modal 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, but now we're of figuring out why it's good for you and how it's good for you.”

Even classic immune health ingredients like elderberry are now shown to have an impact on immune health. A recent op-ed⁵ from Stephen Plattner, PhD, scientific director at Iprona, health & nutrition ingredients, highlights the potential prebiotic benefits of polyphenols found in elderberry. Iprona manufactures ElderCraft, a standardized black elderberry extract distributed by Artemis International in the US. He explains that polyphenols, such as those derived from black elderberry, have been shown to promote the growth of bacteria such as Akkermansia, Bifidobacteria and Lactobacilli. Additionally, one study found that supplementation with black elderberry produced significant changes in microbial diversity. Microbiome benefits may therefore offer a fresh angle for certain immune health ingredients.

Evolution of Consumer Needs

Consumers are becoming more knowledgeable about immune health ingredients, increasingly seeking out staples like vitamin C, vitamin D, and zinc, but also exploring options beyond traditional vitamins, showing growing interest in botanicals and mushrooms for their immune support benefits.

One example of diversifying ingredients, M2 Ingredient’s M2Brew—a mushroom ingredient—designed for coffee applications.⁶ According to the company, it reportedly provides up to 100 times more beneficial mushroom compounds into a finished cup compared to other mushroom coffee products. Perhaps more importantly, there isn’t any type of flavor disruption, showing how immune support ingredients are being adapted for more routine, convenient delivery systems.

It’s clear that consumer needs are evolving, with immune health becoming less of a seasonal concern and more of a daily wellness priority. As research continues to clarify the connections among the gut, immune system, and broader health outcomes, formulators may have new opportunities to develop products that reflect this more integrated view of wellbeing. For the supplement industry, that could mean a continued shift toward multifunctional ingredients and delivery formats that support immune resilience as part of an everyday routine.

References

1. Carabotti M, Scirocco A, Maselli MA, Severi C. The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Ann Gastroenterol. 2015 Apr-Jun;28(2):203-209. PMID: 25830558; PMCID: PMC4367209.
2. Garrido-Mesa J, Gálvez J and Garrido-Mesa N. Editorial: The gut-immune axis: a complex training ground impacting inflammatory pathologies. Front. Immunol. 2023; 14:1274761. doi: 10.3389/fimmu.2023.1274761
3. Park, J.C., Chang, L., Kwon, HK. et al. Beyond the gut: decoding the gut–immune–brain axis in health and disease. Cell Mol Immunol; 2025 22, 1287–1312 doi: 10.1038/s41423-025-01333-3
4. Colli, M. Big Picture on Immune Health. Nutritional Outlook. April 17, 2025. https://www.nutritionaloutlook.com/view/big-picture-on-immune-health. Accessed March 26, 2026.
5. Plattner, S. Polyphenols: The Next Generation of Prebiotics is Ready for Liftoff. Nutritional Outlook. April 21, 2025. https://www.nutritionaloutlook.com/view/polyphenols-the-next-generation-of-prebiotics-is-ready-for-liftoff. Accessed March 26, 2026.
6. Daoust J. M2Brew: A Breakthrough for Brewed Functional Coffee. M2 Ingredients. https://m2ingredients.com/m2brew-a-breakthrough-for-brewed-functional-coffee/. Accessed March 25, 2026.