People often think that different parts of the body work independently, that the skin and gut function separately, even though they’re part of the same body. We tend to think in terms of specific systems, like the gastrointestinal (GI) or circulatory system, or specific organs.

But that’s not how the body works. The gut-skin axis is proof of that.

Increasingly, researchers are discovering links between body systems we never imagined before. Your skin has always been one of the first areas to show changes due to disease. But now we’re learning that your gut health has an enormous impact on your skin, even altering certain conditions.

Let’s learn more:

Your Gut and Skin Are More Similar Than You Think

Your skin and gut aren’t quite as different as they first appear. In fact, they’re two sides of the same coin — how your body interacts with the outside world.

Here’s an amazing fact: your skin and gut are one continuous piece of tissue. You can think of your body as one long tube. The outside of the tube is your skin; the inside is your gut. They’re even a similar size:

• Your skin covers about 270 square feet — a sizeable surface in its own right.

• Your gut lining is even larger, stretching to roughly 323 square feet, making it the body’s biggest interface with the outside world.

They’re your body’s defence against foreign invaders. But while the skin is drier and more resistant to anything getting in, your gut must absorb all the body’s essential nutrients. They’ve both got different mechanisms for stopping pathogens, e.g., the stomach is highly acidic. Though that’s not even so special, your skin produces acid too.

What Is the Gut-Skin Axis?

Given all these similarities, it really shouldn’t come as a surprise that the two share a close relationship.

The gut-skin axis refers to the relationship between the gut microbiome and skin health. Your gut is home to trillions of bacteria and other microorganisms from over a hundred different species. They make up your “gut microbiome.” Far from being harmful, most of these microorganisms provide crucial services, such as aiding digestion, producing essential nutrients, and even supporting skin health.

The relationship is so close that changes in your skin are often a clear indicator of problems in your gut. Disruption to your gut microbiome can cause inflammation, rashes, sensitivity, and other issues.

Here’s how it works:

• Gut microbes help control inflammation. When the microbiome is balanced, inflammation stays low; when it’s disrupted, skin conditions like acne, eczema, rosacea, or psoriasis can flare up.

• They produce metabolites that support the gut and the skin. Short-chain fatty acids (SCFAs) strengthen the gut barrier and help regulate immune responses, which in turn affect skin repair and resilience.

• The immune system connects the two. With most of the body’s immune cells based in the gut, any disruption in signalling often shows up on the skin as redness or sensitivity.

• Stress affects both systems. Stress hormones can disturb gut bacteria and digestion, which can then heighten skin inflammation or reactivity.

• Diet influences the whole axis. A poor diet can upset the microbiome and worsen skin issues, while a fibre-rich, whole-food diet tends to calm both the gut and the skin.

The Links Between Skin and Gut Conditions

Lots of gut conditions influence your microbiome. If you’re struggling with diarrhoea or inflammation in your gut, it can harm the local bacteria, causing symptoms in your skin.

Two specific gut conditions that are associated with skin conditions are:

• Inflammatory bowel disease (IBD) which often occurs along with psoriasis and atopic dermatitis (eczema). All three conditions are autoimmune diseases.

• Coeliac disease which is linked to psoriasis, atopic dermatitis, rosacea, and chronic itch.

In fact, the links are so close that people with these conditions must watch what they eat. If a person with eczema or psoriasis eats highly processed foods (that may harm gut bacteria), it can severely exacerbate symptoms. Conversely, one study in people with psoriasis concluded that eating a Mediterranean diet helped reduce symptoms.

There’s one connecting factor: inflammation.

It’s not an accident that both these conditions are inflammatory conditions linked to an overactive immune system. But even people without these conditions can feel the effects of microbiome disruption.

How Gut Bacteria Lowers Inflammation

Your gut bacteria can either drive or soothe bodily inflammation.

A “good” bacterium like Faecalibacterium prausnitzii produces compounds that have anti-inflammatory effects.

Moreover, gut bacteria are known to produce SCFAs. Some of these are potent anti-inflammatory compounds. For example, butyrate is believed to aid the skin.

Scientists are only now starting to unpick how the gut-skin axis works. But it’s clear, whatever the mechanism, their connection and effects are very real.

Understand Your Gut–Skin Connection with The Functional Gut Clinic

Not sure whether your skin issues are linked to your gut? Or which dietary changes could help calm inflammation from the inside out? The Functional Gut Clinic can guide you.

The Functional Gut Clinic is the UK’s first fully integrated full-spectrum microbiome clinic, offering all of the most advanced tests to assess your gut microbiome. We provide a comprehensive gut health assessment, a personalised action plan based on your results, and ongoing support and specialist care.

Book your consultation today and unlock your gut–skin connection.