The gut-body connection: how your gut health shapes your skin, hormones, mood and more.

Jenni Kiddle

In-House Nutritionist

The importance of gut health is finally being shouted from the rooftops - and we couldn’t be happier. It’s time to celebrate the gut for all it does. Your gut works tirelessly, and far more than just breaking down your lunch. It quietly shapes almost every part of your body - from your energy and mood to your skin, immunity, and hormones.

But how? Well - the trillions of microbes (your gut bugs) living in your digestive tract are constantly sending messages to every system in your body, helping to keep you balanced, resilient, and thriving.

Science calls this your gut-body connection - a complex, two-way network linking your digestive system to your brain, skin, immune defences, energy, and hormones. When your gut is thriving, that network hums in harmony. When it’s out of balance, you feel it everywhere.

Let’s dive into the science of how your gut talks to the rest of your body - and why tending your ‘inner garden’ could be one of the most powerful ways to support whole-body health.

The gut-immune connection

Your gut and immune system are in constant conversation, working together to keep you protected. In fact, around 70% of your immune cells live in your gut, where they’re continuously interacting with trillions of microbes to train, regulate, and fine-tune your body’s defences.

This partnership begins before you’re even born. During pregnancy, maternal microbes, immune cells, and antibodies help prepare the prenatal immune system, ensuring a newborn is ready to respond to the outside world(1).

From the moment you enter the world, your gut microbes get straight to work. They train immune cells to tell friend from foe, teaching them when to respond and when to stay calm. At the same time, your gut lining develops as a selective barrier - allowing nutrients through while keeping harmful microbes and toxins out.

Throughout life, your gut works hard to keep your immune system balanced by:

Controlling inflammation → helping your immune system respond when needed but stay calm around harmless triggers like food or pollen(2).
Protecting the gut barrier → maintaining the tight junctions that prevent unwanted substances from crossing into the bloodstream(3).
Competing with pathogens → crowding out harmful microbes by using up space and nutrients so the ‘bad bugs’ struggle to survive(4).
Producing immune-signalling metabolites → like short-chain fatty acids, which communicate directly with immune cells to keep responses balanced(5).

But this delicate system can easily be disrupted. Stress, poor sleep, medication, illness, or a big change in diet can upset the balance of your gut microbes or damage the gut lining, leading to inflammation and immune ‘misfires’(6).

Supporting both your gut microbes and gut lining is one of the most powerful ways to keep your immune system resilient, regulated, and ready for whatever life throws your way.

The gut-skin connection

If you’ve ever noticed breakouts, irritation, or flare-ups appearing when your gut feels unsettled, you’ve experienced the gut-skin axis in action - a powerful two-way communication network between your digestive system and your skin.

Your gut microbes produce tiny compounds called metabolites that play a big role in controlling inflammation and supporting your skin’s barrier(7). When your gut is balanced, these signals help keep skin calm and resilient. But when your microbiome is out of sync, it can trigger systemic inflammation that shows up on the surface as breakouts, dryness, redness, or conditions like acne, rosacea, eczema, and psoriasis(8).

Your gut lining also plays a starring role. Think of it like a highly selective filter, allowing nutrients through while keeping unwanted compounds out. If that lining becomes weakened, inflammatory molecules can escape into the bloodstream - which can spark flare-ups and accelerate skin irritation(9).

One of your gut’s secret weapons here are short-chain fatty acids (SCFAs) - powerful molecules produced when gut bacteria ferment fibre. SCFAs strengthen the gut barrier, regulate inflammation, and indirectly protect skin health from the inside out.

So, while topical creams and treatments can help, they only work on the surface. Healthy, radiant skin starts deep within - in the gut. Nourish your microbiome, and you build the foundations of a calmer, stronger, natural glow.

The gut-brain connection

Ever had butterflies before a big moment? Or a gut feeling you just couldn’t ignore? That’s the gut-brain axis at work - a constant, two-way conversation between your digestive system and your central nervous system.

Your gut is often called your “second brain” - and for good reason. It’s lined with millions of nerve cells that communicate directly with your brain via the vagus nerve - essentially a biological hotline carrying real-time updates between the two(10).

Your gut also plays a key role in producing neurotransmitters and chemical messengers. Gut microbes influence brain serotonin - through precursors like tryptophan, via the vagus nerve, and through immune and endocrine signaling - helping to shape mood, stress resilience, sleep, and focus. The gut also produces other neurotransmitters, such as dopamine and GABA, which contribute to emotional and cognitive balance(11).

When your gut is balanced, these signals help stabilise mood, manage stress, support better sleep, and sharpen cognitive function. But when there’s imbalance, chronic inflammation, or damage to the gut lining, this group chat between gut and brain can get scrambled -which can show up as increased anxiety, mood dips, brain fog, or poor sleep quality.

The gut-hormone connection

Perhaps one of the most fascinating conversations happening inside you is the one between your gut and your hormones - a delicate feedback loop influencing everything from cycles to energy

A key player here is the estrobolome, a group of gut microbes that process and recycle oestrogen. When this system works smoothly, the body uses what it needs and clears the rest - helping to support healthy cycles and mood. But when there’s gut dysbiosis (an imbalance in gut bacteria), things can slow down. Constipation means excess oestrogen isn’t excreted properly and instead gets recirculated around the body, which can amplify symptoms like PMS, heavy periods, bloating, or hormonal breakouts (12) (13).

Hormones also talk back. Fluctuations in oestrogen and progesterone during the menstrual cycle, pregnancy, and menopause can influence how your gut functions - impacting motility and microbial diversity (yes , period poops are a thing!) (14) (15).

But the gut’s reach stretches far beyond sex hormones. Here’s how it connects with other key players:

Stress & cortisol → Chronic stress can disturb gut flora, increase gut permeability, and spark inflammation - while gut imbalance can heighten stress responses, creating a feedback loop(16).
Sleep hormones → Your gut helps produce serotonin and melatonin, vital for deep, restful sleep. When this system falters, sleep can wobble too (17).
Appetite & metabolism → Gut cells release hormones like GLP-1 and PYY, signaling when satiety's reached and helping balance energy and hunger (18).
Thyroid & energy → A balanced gut enables absorption of thyroid-essential nutrients, supporting steady hormone production and sustained energy.

Because your hormones work as a network, a disrupted gut can ripple into mood swings, fatigue, cravings, dry skin, irregular cycles, and digestive chaos. Nurturing your microbiome and gut lining is one of the most powerful ways to bring hormonal balance back into harmony.

Balance begins within

When your gut ecosystem is thriving, everything flows. But when your gut falls out of balance, you feel it everywhere - in your focus, sleep, stress levels, mood and digestion. And because all the systems are connected, it also influences your energy, vitality, and even long-term health and longevity.

Your gut isn’t just part of the picture - it’s the foundation beneath it all.

This is why we created True Biome. Formulated with three carefully chosen ingredients, it takes a simplified, science-backed approach to gut health:

PHGG → A gentle, prebiotic fibre that feeds your beneficial bacteria and supports healthy digestion.
L-glutamine → An amino acid that nourishes and protects your gut lining, helping to maintain a strong barrier.
HK L-137 postbiotic → A clinically studied postbiotic that supports immune function and gut balance from within.

All in a neutral tasting powder. A simple daily ritual, working together to bring your gut - and the rest of your body - back into balance.

Because when your gut thrives, so does everything else.

References

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The gut-body connection: how your gut health shapes your skin, hormones, mood and more.

Jenni Kiddle

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