Healthy Skin Begins in the Gut: Why Short-Chain Fatty Acids Matter in the Skin-Gut Axis

Short-chain fatty acids (SCFAs) and the skin-gut axis.

By Marcelline Goyen, BSc Dermal Therapist, Skin-Gut Axis Specialist & Author Published: July 23, 2026

Introduction Short-Chain Fatty Acids, Skin and Gut

The skin-gut axis is attracting increasing scientific attention. Research suggests that beneficial gut bacteria and the short-chain fatty acids (SCFAs) they produce may help support the intestinal barrier and immune function—processes that are increasingly being studied in inflammatory skin conditions such as acne, eczema, rosacea and psoriasis.

When I was working as a dermal therapist, I gradually noticed a pattern that I could no longer ignore. Many of my patients with persistent skin conditions also struggled with their digestion. Constipation, bloating, food intolerances or simply "a sensitive gut" often seemed to accompany inflammatory skin conditions such as acne, eczema and rosacea.

At first, I simply saw it as an interesting observation. But over time, it became one of the reasons I decided to study gut health alongside skin health. I wanted to understand whether these two organs were communicating more closely than we once believed.

Introducing Prebiotic Fibers in the Dermal Therapy Practice

One of the first changes I introduced in my practice was the use of prebiotic fibres, particularly inulin and psyllium husk, whenever appropriate and within my professional scope. I still remember how delighted some patients were when, after years of constipation, they finally experienced comfortable, regular bowel movements.

As I continued combining dermal therapy with gut therapy, I also noticed something else. Patients often told me that as their digestion improved, they simply felt better overall, and some became more aware of changes in their skin as well. These were observations from my own clinical practice rather than scientific proof, but they sparked my curiosity. They made me wonder whether improving bowel habits was only one part of a much bigger story.

Looking back now, I believe those prebiotic fibres were doing far more than supporting bowel regularity. They were also feeding the beneficial bacteria that produce short-chain fatty acids. At the time, I didn't yet know how important those tiny microbial metabolites would turn out to be.

How Gut Bacteria Produce SCFAs

Today we know that those same fibres are also food for some of our most beneficial gut bacteria. What fascinated me most was that something as simple as feeding our gut bacteria could influence a biological process far beyond digestion. That realisation completely changed the way I looked at chronic inflammatory skin conditions.

These bacteria ferment dietary fibres and produce short-chain fatty acids (SCFAs), mainly butyrate, acetate and propionate. Although tiny in size, these molecules play an important role in maintaining a healthy intestinal environment. They nourish the cells lining the colon, help maintain the protective mucus layer, support the integrity of the intestinal barrier and contribute to balanced immune responses.

Why does this matter?

Why the Intestinal Barrier Matters

Because the intestinal barrier is one of the body's most important protective interfaces. It allows nutrients to pass into the bloodstream while helping to keep potentially harmful substances where they belong—inside the gut. Research into increased intestinal permeability, often referred to as "leaky gut", is still evolving. Although scientists continue to investigate its exact role, growing evidence suggests that impaired barrier function may contribute to chronic inflammatory conditions, including several inflammatory skin diseases.

The exciting part is that our gut bacteria help maintain this barrier every single day.

The Three Major Short-Chain Fatty Acids (SCFAs) and their primary functions

Short-chain fatty acid (SCFA)	Mainly produced by	Why it matters
Butyrate	Faecalibacterium prausnitzii, Roseburia, Eubacterium spp.	Nourishes colon cells, supports the intestinal barrier and helps regulate immune responses.
Acetate	Bifidobacterium spp.	Supports microbial balance and serves as a building block for other beneficial bacterial metabolites.
Propionate	Bacteroides spp., Veillonella spp.	Contributes to immune regulation and normal gut metabolism.

What Does the Scientific Evidence Show?

One of the most exciting developments in recent years is that this is no longer simply an interesting theory. A comprehensive review published in 2025 concluded that alterations in the gut microbiome are consistently observed across several inflammatory skin diseases, including atopic dermatitis, acne, rosacea and psoriasis. The authors also describe the growing evidence that microbial metabolites—including short-chain fatty acids—play an important role in immune regulation and communication along the skin-gut axis.

Another recent review, focusing specifically on short-chain fatty acids, describes butyrate, acetate and propionate as key signalling molecules produced by beneficial gut bacteria. Rather than simply serving as an energy source for colon cells, these microbial metabolites appear to influence intestinal barrier function, inflammatory pathways and immune balance—all mechanisms that are increasingly being investigated in relation to chronic inflammatory skin diseases. While much remains to be learned, this growing body of research helps explain why supporting the gut microbiome has become such an exciting area within dermatology.

Can You Tell Whether You Produce Enough SCFAs?

One question I am often asked is whether you can actually tell if you produce enough short-chain fatty acids. The honest answer is: not directly.

At the moment, there is no simple home test that can tell you whether your gut produces sufficient amounts of SCFAs. However, your lifestyle and bowel habits may provide useful clues. If vegetables, legumes and whole grains rarely appear on your plate, or if constipation has quietly become your normal, your gut microbes may not be receiving enough of the dietary fibres they need to produce these beneficial compounds. Of course, these signs do not prove low SCFA production, but they may indicate that your microbiome could benefit from more fibre diversity and a greater variety of beneficial microbes.

Note: Although SCFAs can be measured in stool or blood samples, and microbiome analyses can provide insight into the presence of SCFA-producing bacteria, there is currently no clinically available test that can accurately determine how much SCFA production is taking place in an individual’s colon. This is partly because most SCFAs produced are rapidly absorbed by the intestinal lining and because microbial activity cannot be fully determined from microbiome composition alone.

The encouraging news is that supporting your beneficial bacteria does not necessarily begin with expensive supplements. For most people, it starts with everyday nutrition. Eating a wider variety of vegetables, fruit, legumes, nuts, seeds and whole grains provides the fibres your gut microbes depend on. Foods naturally rich in prebiotic fibres—such as onions, garlic, leeks, asparagus and chicory—can help nourish beneficial bacteria and support SCFA production. Psyllium husk may also support bowel regularity for many people, provided it is introduced gradually and consumed with sufficient water.

Looking Back on Clinical Practice

Looking back at my years in practice, I realise that helping patients improve their bowel habits was probably only the visible part of the iceberg. By increasing their intake of prebiotic fibres, we were also feeding the microbes that produce short-chain fatty acids—small molecules that help maintain a resilient intestinal barrier and support communication between the gut and the immune system.

Today, the growing body of research on the skin-gut axis provides a scientific explanation for what I had already begun observing clinically many years ago. It reminds us that the skin does not function in isolation. Healthy skin is influenced by many factors, and one of them may well be the remarkable community of microbes living inside our gut.

Conclusion

As a dermal therapist, I have always believed that we should never look at the skin in isolation. We should certainly treat the skin itself, but we should also ask why inflammation persists, why the skin barrier struggles to recover, and whether the gut might be part of the bigger picture. We do not yet have all the answers, but the science behind the skin-gut axis is advancing rapidly—and I believe it will continue to reshape the way we think about skin health in the years ahead.

Further Reading

For readers who would like to explore the science behind the skin-gut axis in more detail, these recent review articles provide an excellent starting point. The role of short-chain fatty acids, intestinal permeability, the microbiome and inflammatory skin diseases is discussed extensively in my textbook The Amazing World of the Skin-Gut Axis, including the Role of the Microbiome (Volume II, 2024), or read my blog about healthy food for a healthy gut.

• Zhao Y, et al. The gut-skin axis: Emerging insights in understanding and treating skin diseases through gut microbiome modulation. International Journal of Molecular Medicine. 2025.PubMed: https://pubmed.ncbi.nlm.nih.gov/41041846/

• Deng Y, et al. The role of short-chain fatty acids in inflammatory skin diseases. Frontiers in Microbiology. 2023.PubMed: https://pubmed.ncbi.nlm.nih.gov/36817115/

• Goyen M. The Amazing World of the Skin-Gut Axis, including the role of the Microbiome Volume II (2024). ISBN-13 ‏ : ‎ 979-8336973785. [BOOK]

• Goyen M. De huid-Darm Connectie Volume I (2019) EAN 9789463456210 [BOOK 1]

⚖️ Medical Disclaimer: The information provided on this website, including articles, textbook references, and educational materials, is for informational and educational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified healthcare provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

Marcelline Goyen, BSc | Dermal Therapist | Skin-Gut Axis Specialist | Author

Founder of www.skin-gut-axis.com

About Marcelline Goyen, BSc Marcelline Goyen, BSc, is a dermal therapist (formerly practicing), international educator, and author specializing in the complex interactions of the skin-gut axis. With over two decades of clinical experience, she is known for her pioneering work on the skin-gut-brain connection and integrative approaches to skin health. To make her knowledge more widely accessible, her work has culminated in the publication of two books, which are used as reference works in the field of holistic skin rehabilitation. Alongside her writing, she shares her insights globally through masterclasses and webinars.

Discover more about her books and clinical vision at www.skin-gut-axis.com, or connect with Marcelline on LinkedIn.