Getting the bacterial balance right in your gut can be tricky, but it can have a profound impact on your health, writes CHARLOTTE ROWLEY.

Last issue, we discussed the role of our genes and our epigenetic markers. Now it’s time to consider the other organisms that inhabit our body – what we collectively call the microbiome. If you’re not familiar with the term “microbiome,” you might be more familiar with the term “gut bacteria.” You might also have seen the Inner Health Plus advert – or supermarket yoghurt packaging – which talks about the balance of good and bad bacteria in your body.

Before you freak out and down a tub of probiotics, it’s important to know that having bacteria in our bodies is totally normal and can actually make us healthier. While there are microbial populations (communities of bacteria) in many locations in the body, we typically focus on the community that lives in your gut.

The bacteria in your gut help to break down undigested food (that roughage that would otherwise end up in your stools). Some of the byproducts that bacteria make during this process can support our immune system, affect our metabolism, and are involved in the development of cardiovascular disease, cancer, and type 2 diabetes. Whether our gut bacteria are here to help us or hurt us depends on the type of bacteria that calls your gut home.

While we may not know the exact mechanisms, there is evidence to indicate that certain bacteria can be protective against type 2 diabetes, while others can promote the development of type 2.

Understanding what makes up a “healthy” microbiome population is tricky. Overall, we know that we want to have a lot of different types of bacteria, and there are some groups of bacteria which are thought to be healthier than others. Part of the reason an exact balance is difficult to pin down is due to the interactions between our gut bacteria and our genes. For example, our microbiome can influence which genes are expressed more often. Alternatively, bacteria can increase or reduce inflammation, which is a constant issue in diabetes. While we may not know the exact mechanisms, there is evidence to indicate that certain bacteria can be protective against type 2 diabetes, while others can promote its development.

Now we know how important our microbiome is, how can we improve the bacteria in our guts to improve our health? This is a tricky question to answer. The population in our microbiome is pretty flexible in the baby and toddler age, but as we get a little older, our microbiome becomes much more stable. Things such as antibiotics and some other medications, infections, and illnesses can affect your microbiome, for better or for worse. Some surgeries can also have an impact. But for most of us, the easiest way to improve our microbiome is to eat a healthy diet.

Healthy bacteria tend to have something in common – they thrive on fibre. You may have heard about pro- and prebiotics. Fibre is prebiotic, which just means it is the food that the good bacteria eat. By ensuring that our good bacteria have plenty of fibre for food, we can improve the chances that those bacteria will take up most of the space and push out less healthy bacteria.

Bacteria that are associated with negative health outcomes tend to thrive on less healthy food (like high-fat and high-sugar foods – think burgers, chips, and chocolate). Giving your body a diet high in fibre is not just good for your diabetes management (and broader health) but also for the workers in your gut.

What about probiotics? There’s no probiotic available in Australia that is specific to treat type 2 diabetes. As we’ve seen, type 2 is promoted by various genetic, epigenetic, and microbiome factors, not to mention lifestyle aspects such as diet and exercise. Because there are so many potential genes and epigenetic marks to impact your risk of diabetes, with each of these potentially interacting with bacteria in different ways, there is no single “ideal” microbiome population.

In the future, we may have more options to adjust our microbiome to reduce diabetes risk (like the new faecal transplants that are proving promising for people with persistent gut issues). For now, the best thing you can do is give your healthy bacteria the fuel they need – lots of fibre.