What is the gut microbiome and why is it important?

The gut microbiome is made up of trillions of microorganisms (also known as microbes) that live within the intestinal tract of our digestive system. Every human has their own unique microbiome which is made up of both good and bad bacteria, fungi and viruses. Think of the gut microbiome like the “house” where these microbes live. Now I know what you may be thinking… little microbes living within my gut ?.. how horrifying! However, these microbes are important for our health and play an important role in digesting the foods we eat as well as assisting with the absorption and production of important nutrients. They also assist with regulating our immune system and protect us against harmful bacteria and viruses.

As this is a newly emerging area of research, the current literature is quite limited in the full understanding of the gut microbiome and its complexes. However, research has revealed that the gut microbiome plays a fundamental role in impacting human health and the development of diseases such as obesity, autism, depression, celiac disease, irritable bowel syndrome and allergies, to name a few. Interestingly, recent studies have also revealed neurological disorders such bipolar disorder and schizophrenia may also be associated with disruptions in the microbiome.

Having the right amount of microbes and the right combination of species within your gut microbiome is important. Studies have shown that the more microbial diversity we have the more beneficial this is for our health, whilst disruptions to our gut microbiome and reductions in microbial diversity have been linked with poorer health outcomes. Issues also occur when an overgrowth of certain species disrupt this balance.

The impact of diet on our gut microbiome

One of the greatest influences on microbe diversity within our gut microbiome has been linked to our diet. A healthy diet rich in fruits and vegetables, prebiotics, probiotics and more specifically fibre, has been shown to improve our gut microbe profile. Studies have revealed that changes made to our diet can impact our gut microbiome in as little as 24 hours, demonstrating just how quickly our diet affects our microbe profile!

What is fibre and why is it so important?

Fibre is a type of carbohydrate found in plant-based foods such as fruits, vegetables, whole grains, beans and legumes. It serves to regulate our digestive health and assist with regular bowel movements. Dietary fibre is also the best fuel for our gut microbes as they need this to survive. When our gut microbes digest fibre they produce short-chain fatty acids that nourish the gut barrier, improve our immune system and reduce inflammation which therefore reduces the risk of cancer. A low fibre diet results in less fuel for gut bacteria to thrive, causing them to starve and die, resulting in reduced diversity. Some microbes even begin to feed on the mucus lining of the intestinal tract which can cause “leaky gut” syndrome in which bacteria and toxic waste products can leak into the bloodstream.

So what can you do to improve your gut microbiome?

To help support the growth and diversity of healthy gut microbes it’s important to consume a diet rich in fibre, including a wide variety of fruits, vegetables, whole grains, prebiotics and probiotics. It is recommended you aim for 25-30g of fibre per day, and we have some easy tips to help you achieve this!

Six easy ways to increase your fibre intake:

1. Choose fibre fortified breakfast cereals
2. Switch to wholemeal or multigrain bread
3. Snack on fruits, vegetables, nuts, seeds and wholegrain crackers
4. Add extra vegetables to your meals wherever you can
5. Leave the peel/skin on your fruit/vegetables (ie apples, potatoes, cucumbers)
6. When reading nutritional labels aim for a minimum of 7g of fibre for meals and 3g of fibre for snacks.

If you do find that you are struggling to increase your fibre intake, adding a fibre supplement such as ‘Metamucil’ into your day is a great way to help. It’s important to remember that when increasing your fibre intake you will also need to increase your water intake to avoid any discomfort or constipation and to assist with regulating bowel movements.

In summary, the gut microbiome plays an important role in our overall physical and mental wellbeing. It’s important that you prioritise dietary fibre in your daily diet to ensure you are creating a healthy gut environment!

Written By Annalise Farah, Accredited Practicing Dietitian (APD) – BMedSc & MND