Gut health explained: What your microbiome means for your wellbeing

“Gut health” has become a buzzword - from yoghurt ads promoting probiotics to blogs urging you to listen to your “gut feeling.” Behind the hype lies a growing body of research showing that your gut does far more than just digest food. It influences almost every aspect of your health: from your immune system and hormones to your mood and energy.

So what does “gut health” really mean? And why is the microbiome so important? Let’s break it down step by step.

Table of contents

1. What the gut and microbiome actually are

2. Why the gut microbiome matters for your health

3. The surprising gut-brain connection

4. Factors that shape your microbiome

5. What happens when your gut is out of balance

6. How to support healthy gut function

What is the gut microbiome?

Your gut makes up your entire digestive tract - from mouth to stomach to intestines, with help from the liver, pancreas, and gallbladder. It’s the pathway along which food is broken down, absorbed, and eventually eliminated.

Living within it is the gut microbiome: an ecosystem of trillions of microbes - mainly bacteria, but also fungi and viruses - that live in your intestines. Most are friendly and help keep the harmful ones in check.

Fun fact: You have more microbes in your body than human cells. That means your microbiome contains more genetic material than your own DNA.

Everyone has a unique microbiome. You get your first microbes at birth (via vaginal delivery or C-section), then your microbiome develops through breastfeeding and continues to be shaped by your diet, environment, and lifestyle.

Why your gut microbiome matters so much

Research into the microbiome is still young - most studies are less than 20 years old. Yet scientists agree that the microbiome is central to many vital processes:

• Digestion: Gut bacteria break down fibres and carbohydrates that our body can’t digest on its own. In the process, they produce vitamins (like K and B vitamins) and short-chain fatty acids that fuel our cells.

• Immune system: Around 80% of your immune cells live in the gut. Good bacteria compete with pathogens and help your immune system recognise threats.

• Hormones: Your gut is also a hormone-producing organ. Specialised cells release insulin, ghrelin, and leptin, which regulate appetite, blood sugar, and energy balance. Hormones like oestrogen are also recycled via the gut.

💥 When the immune system stays overactive for too long, it can lead to chronic inflammation. This is linked to conditions like autoimmune disease, obesity, and type 2 diabetes.

The gut-brain connection

Your gut and brain are in constant communication via the gut-brain axis. Microbes in your gut can stimulate or even produce neurotransmitters like serotonin and dopamine - the same chemicals that affect mood, sleep, and stress.

🧠 Did you know? About 90–95% of serotonin (the “happiness” hormone) is made in the gut, not the brain.

That’s why an imbalanced microbiome isn’t just linked to IBS, but also to anxiety, depression, and brain fog. Stress, in turn, can send signals to the gut, worsening digestive issues like bloating and cramps.

What shapes your gut microbiome?

Your microbiome changes daily. Key factors include:

• Diet: Fibre-rich foods (vegetables, fruits, whole grains) feed good bacteria, while processed foods and sugar fuel less beneficial bacteria. Fermented foods (yoghurt, kimchi, kefir) add live cultures, while prebiotics (garlic, onions, bananas) feed them.

• Medication: Antibiotics, anti-inflammatories, and antacids can reduce microbiome diversity. A higher diversity usually means a more resilient microbiome.

• Lifestyle: Stress, poor sleep, smoking, and alcohol can harm the microbiome, while regular movement and deep, restorative sleep support it.

• Environment: Whether you were born vaginally or by C-section, exposure to nature, pets, and even air pollution all influence microbiome diversity.

🥦 Tip: Variety matters. Research suggests that eating 30 different plant foods a week helps keep your microbiome happy. Each plant contains unique fibres and nutrients that different bacteria need to grow.

When your gut is out of balance

An imbalanced microbiome - known as dysbiosis – occurs when harmful microbes gain the upper hand. This can happen due to antibiotics, chronic stress, poor diet, or pollution.

Symptoms are broad: bloating, diarrhoea, constipation, skin problems like eczema, brain fog, or fatigue. More severe cases are linked to IBS, IBD, autoimmune diseases, and metabolic disorders.

🪱 Leaky gut explained: When dysbiosis weakens the gut lining, toxins can enter the bloodstream. Your immune system reacts to these “foreign” particles with inflammation, which can trigger ongoing health problems.

The good news: you can restore balance. Eating a wider variety of plants, adding fermented foods, cutting down on sugar and processed foods, and focusing on movement, sleep, and stress reduction all help your microbiome recover.

Final thoughts

Gut health isn’t just a trend - it’s a foundation of overall wellbeing. From digestion and immunity to hormones and even your mood, your microbiome plays a bigger role than most of us realise.

The best way to support your gut isn’t through perfection, but small, steady changes. Start by adding more plants, treating your body with more kindness in times of stress, and giving your gut time to adjust. Over time, these small steps can add up to major shifts in your health.

Key takeaways

• Your gut microbiome is a vast community of microbes that influence digestion, immunity, hormones, and mental health.

• Gut health is shaped by factors like genetics, diet, lifestyle, environment, and medication.

• Imbalance (dysbiosis) can cause digestive issues, skin conditions, fatigue, and even chronic disease.

• Supporting your gut doesn’t require perfection - begin with fibre-rich foods, add fermented foods if you like, reduce stress, move regularly, and prioritise quality sleep.

References:

Gomaa, E. Z. (2020). Human Gut microbiota/microbiome in Health and diseases: a Review. Antonie van Leeuwenhoek, 113(12). https://doi.org/10.1007/s10482-020-01474-7

Kim, N. V., & Sheveleva, S. A. (2021). The role of the gut microbiome in health and diet-related diseases. Voprosy Pitaniia, 90(6), 31–41. https://doi.org/10.33029/0042-8833-2021-90-6-31-41

Rathore, K., Shukla, N., Naik, S., Kumar Sambhav, Kiran Dange, Bhuyan, D., & Imranul, M. (2025). The Bidirectional Relationship Between the Gut Microbiome and Mental Health: A Comprehensive Review. Cureus. https://doi.org/10.7759/cureus.80810