Good bacteria are vital for good health. There are trillions of these microscopic cells living inside us, along with other microorganisms including viruses and fungi. Collectively, they form a community of microbes – a complex ecosystem called the microbiome.
These microbes can and do live in lots of places in and on our bodies, including our mouth, nose and skin. But they are most often found in our digestive system, particularly in the large intestine. This community of microbes is referred to as the gut microbiome.
Scientists have long known that the gut microbiome is important for our health. It helps keep our digestive systems running smoothly, breaking down food for nutrients and transforming vitamins into useful forms.
But scientists are finding more and more functions linked to the gut microbiome, and realising that its impacts are more widespread than previously thought. For example, altered gut bacteria have been found in obese mice, and in many different disease states.
The gut microbiome might even affect our mental health, with some evidence linking it to disorders such as depression and anxiety, although we still can’t be sure it causes those conditions. And at least one study has shown that there is a correlation between microbiome diversity and sleep quality.
What we can say for sure is that changes to the microbiome are present when there are inflammatory diseases. While it is too early to tell if one causes the other, it means that an altered gut microbiome can be a biomarker for disease. Scientists have observed changes in the composition of the microbiome taking place in inflammatory diseases such as type 2 diabetes and fatty liver disease.
The good news is that while you may not be able to see your microbiome, you can change it. Environmental factors play a big role in determining the bacteria to which you are exposed.
The exact mechanisms are not always clear, but it appears that some microbes, or molecules that they produce, can move from the gut to affect organs such as the liver, causing inflammation.
You should also avoid the unnecessary use of antibiotics, both to avoid killing your good gut bacteria and also to help prevent the development of antibiotic resistance.
The most important factor, though, is the food you eat. A good diet, along the guidelines you can read in Diet is your best bet, will help support good bacteria and keep your gut – and you – healthy.
Scientists are finding more and more functions linked to the microbiome, and realising that its impacts are more widespread than previously thought.
Three Fs for good gut health, according to Professor Tim Spector, head of the British Gut Project:
- Fibre – and plenty of it
- Fruit and veg – in as many varieties as possible
- Felines – spending time with animals increases your microbial diversity
BY THE NUMBERS
The percentage of our gut microbiome that is unique to each individual