"All disease begins in the gut," said the Ancient Greek philosopher Hippocrates.
Some 2,000 years later, that idea holds up remarkably well. Taking care of gut health supports overall wellbeing in a range of ways, and has been linked to digestive health, immune function, and metabolic conditions such as obesity.
Researchers have also identified a nervous system within the gut, sometimes called the "second brain," which communicates directly with the brain via the gut-brain axis. This connection is increasingly understood to play a role in mood and mental wellbeing, with ongoing research exploring links to conditions like anxiety and depression.
In short, the overall wellness of both body and brain is closely tied to gut health.
It's All About Bacteria
So what actually determines how well your gut functions? Largely, bacteria – around 100 trillion of them, in fact, alongside viruses and fungi, together making up what's known as the microbiome.
Everyone's microbiome is unique, shaped by factors present from birth, along with diet, environment and lifestyle over time.
Bacteria live throughout the body, but those in the gut have the biggest influence on overall health. Some bacteria help fight inflammation, while others promote it. In a well-functioning gut, these balance each other out. When that balance is disrupted, inflammatory bacteria can dominate, producing byproducts that affect the gut lining and bloodstream, spreading inflammation more widely through the body.
Certain bacterial imbalances have been linked to lower immune function, increased allergy risk, and higher risk of chronic conditions including diabetes and heart disease. The gut also plays a central role in nutrient absorption, so a poorly functioning microbiome can contribute to nutrient deficiencies over time.
This Is Where Food Comes In
Diet plays a major role in shaping and maintaining a healthy gut microbiome – what you eat directly influences which bacteria thrive.
The encouraging news is that even years of less-than-ideal eating habits can be improved. Dietary changes can begin shifting microbiome composition within days, meaning it's never too late to start making a positive difference.
What to Eat for a Healthy Gut
Prebiotics
Prebiotics are fibres and natural compounds that feed beneficial gut bacteria and support microbial diversity. Good sources include onions, garlic, asparagus, bananas and Jerusalem artichoke.
Probiotics
Probiotics are foods containing live beneficial bacteria that help populate the gut and compete with less helpful bacterial strains. Good sources include live yoghurt and fermented foods such as sauerkraut, kimchi and miso. If you're looking to support this more directly, a gut health probiotic supplement is another option worth considering alongside dietary changes.
Add More Fibre
Most people don't get enough fibre day to day. Fibre feeds beneficial bacteria directly, and eating fibre-rich foods regularly supports a healthier gut. Gut bacteria extract energy, nutrients and vitamins from fibre, which can support immunity, help manage inflammation, and support healthy weight management.
Choose Whole Grains
Whole grains such as quinoa and oats contain fibre that passes through the small intestine largely intact, reaching the colon where it feeds gut bacteria directly. Good sources include wholegrain rice, brown or rye bread, buckwheat and quinoa.
Add Antibacterial Spices
Spices like garlic, ginger, cumin and turmeric have natural antibacterial properties that may help keep less beneficial bacteria in check.
Try Dark Chocolate
Dark chocolate (ideally 70%+ cocoa) contains fibre and polyphenols, compounds that beneficial gut bacteria can use as fuel. Polyphenol-rich foods are generally anti-inflammatory and may support healthy blood pressure and cholesterol. Other good sources include red grapes, artichoke, green tea and cherries.
Don't Forget Apples
Some research suggests apples, particularly green varieties, may support beneficial gut bacteria – both eaten raw and, interestingly, when stewed.
Foods to Limit
Processed Foods
Diets high in processed foods and refined carbohydrates are associated with reduced bacterial diversity and increased gut inflammation. Worth limiting: white bread, white rice, ready meals and lower-quality cooking oils.
Unnecessary Antibiotics
Antibiotics, along with some over-the-counter medications such as NSAIDs, can disrupt the gut microbiome. Use them only when genuinely needed and as advised by a healthcare professional.
Chronic Stress
Research suggests past stressful periods can continue to affect gut health well after the event itself. Stress can also suppress immune function as the body prioritises responding to the immediate stressor. Regular exercise is a well-supported way to help manage stress and support gut health at the same time.
Poor Sleep
Even short-term sleep deprivation can negatively affect the microbiome. Prioritising a consistent wind-down routine and enough quality sleep supports gut health alongside diet.
Take Control of Your Gut Health
Sub-optimal gut health has been linked to a wide range of conditions, partly because the gut plays such a central role in immune function and inflammation. Improving your diet with more fibre, prebiotics, probiotics and polyphenol-rich foods, alongside managing stress and prioritising sleep, all support a healthier gut microbiome and better overall health. If you'd like a clearer picture of where your gut health currently stands, our gut health tests and supplements are a good place to start.
