Why The Gut Microbiome Is Vital For Health

In partnership with Healthspan

Healthy gut bacteria doesn't just improve digestive health. It can also lead to better mental wellbeing and reduce the risk of many chronic diseases.

Recent advances in microbiome medicine have begun to uncover exactly how the microbiota, the trillions of microorganisms that make up the gut microbiome, have an effect on the body far beyond the digestive system. 

When we are healthy these bugs live peacefully side by side in the small and large intestines and help perform crucial roles in the body, including digesting food, synthesising some vitamins (including B vitamins and vitamin K) and protecting immunity. 

Each of us has a unique microbiome, originally determined by genetics, but over time shaped by lifestyle. A disturbance in the balance of the microbiota, whether from illness, poor diet, lack of sleep, dehydration, chronic stress or prolonged use of medications such as antibiotics, puts us at greater risk of disease.

 

 

The Brain-Gut Axis

Research also shows that the brain affects our gut health and the gut, in turn, affects our mental health. This two-way communication between the central nervous system and the enteric (gut) nervous system is known as the gut-brain axis (GBA). Our 'gut feelings', such as butterflies in our stomach, are now acknowledged to be part of this complex communication network between the brain and the 'second brain' in our belly. 

Gastrointestinal experts and nutritionists say that the key to maintaining or improving these lines of communication, and to generally improving your wellbeing, is to create, and maintain, a delicate balance of bugs in your gut. 

Diet is, unsurprisingly, significant in shaping the microbiome, through promoting the growth of beneficial bacteria and holding back the accumulation of harmful ones. As Epidemiology Professor Tim Spector, from King's College London, says, 'When you eat you are not just nourishing your body; you're feeding the trillions of microbes that live inside your gut.'

His research shows that those who eat a diet with minimal processed foods and plenty of plant-based ones, such as vegetables, fruits and pulses, or healthy animal-based ones such as oily fish, yogurt and eggs, are more likely to have higher levels of 'good' gut microbes.

 

 

Microbiome Healing Treatments

Our balance of gut bugs can, unfortunately, be thrown out of balance. This can occur after a bout of food poisoning, for example, or a course of antibiotics.

Increasing use of antibiotics has contributed to the rise of antibiotic resistance, which has made some bacterial diseases like Clostridium difficile (C diff), which causes chronic diarrhoea and potentially life-threatening damage to the colon, difficult to treat. Where standard treatments don't help, a procedure known as faecal microbiota transplantation (FMT) is currently used in the UK for patients suffering from repeated C diff infections. 

This involves transferring liquid stools from a healthy donor into the intestines of a patient, and has been shown to restore the balance of bacteria in the recipient's gut. Research has shown the procedure to be up to 90% successful in treating recurrent C diff. 

What's more, a range of ongoing trials in the UK is looking at how the procedure could potentially treat conditions including anorexia, autism and dementia. 

 

 

Increased diversity

Although there is no single treatment, food, food group or supplement that will magically improve gut microbiota, research shows that eating a diverse diet is what allows different gut microbes to thrive. High-fibre food like fruits, vegetables, pulses, seeds and nuts are important for literally feeding the bugs and helping them to increase in number. 

Similarly, prebiotic foods such as Jerusalem artichokes, onions, garlic and leeks (prebiotics act as a kind of fertiliser, helping to feed the 'friendly' bacteria), and probiotic ones containing beneficial live microbiota, such as natural unsweetened live yogurt, sourdough bread and fermented foods and drinks, offer related benefits. 

A 2021 study from Stanford University found that fermented food and drinks such as kefir, live yoghurt, sauerkraut, kombucha, kimchi and miso were better at improving gut bacteria diversity than fibre alone.

 

Good Gut Health For Life

What do those who study gut microbes do to protect their own? Professor Spector's principal advice is to "eat as many diverse plants as you can", so not only vegetables and fruit, but nuts, seeds, pulses, spices and herbs. His go-to gut-friendly meals include homemade sourdough with goat's cheese, or kefir with blueberries and nuts and seeds. He also meditates and cycles daily. 

Clinical GI Scientist Dr Anthony Hobson, from The Functional Gut Clinic, echoes the professor's advice, adding: "I try not to eat or drink anything that can weaken the gut lining, like excessive alcohol. To nurture the good bugs I eat a diverse range of foods, especially fruit, veg, nuts, seeds and pulses. If I need an extra boost I might take a probiotic or a kefir yoghurt drink. Also, I might take a prebiotic supplement to 'feed' the good bugs. I can do lots of things to help my gut, and in turn my gut protects me!"