What is the gut microbiota?

The gut microbiome consists of trillions of microorganisms also called the microbiota or microbes. [1] They exist along the digestive system supporting our health, wellbeing and functioning of our bodies. Many species of bacteria, fungi, viruses and protozoans create the gut microbiome. The colonisation of the gut microbiota begins from birth and it is influenced by several lifestyle factors including our diet and environment. [1]

What is the role of the gut microbiota?

The gut microbiota supports the process of digestion. Certain types of fibres that cannot be digested is broken down by our gut microbiota. Prebiotics found in banana, garlic, onion, leeks, oats are generally the fuel that supports these gut microorganisms. When our gut microbiota is thriving and fueled by these prebiotics it helps us obtain energy and nutrients from the food we eat. [2] With the digestion of certain fibres there can be a beneficial compound left behind known as short chain fatty acids which can leave the digestive system, enter our circulation and have a wide range of benefits. These compounds can signal and affect metabolism, manage appetite, sleep, mood and even show anti-inflammatory properties, which is important to sustain good health and prevent diseases. [2]

Additionally, the gut microbiome is involved in the gut brain axis whereby, our gut and our brain are linked with a nerve connecting a two-way communication system. Due to this connection there is a link between our diet and mental health. Changes that take place in the gut microbiota could be associated with the development of anxiety, depression and other neurodegenerative conditions. [3] This is why it is imperative that we support our gut microbiota through food and nutrition in order to function at our best.

What you can do to support your gut microbiota?  [2,4]

• Increase plant-based food items in your diet. Diverse plant-based food such as fruits, vegetables, whole-grains, nuts, seeds, legumes should be included in your diet.
• Add variety to your diet. Do not eat the same fruits and vegetables each week. Alternate the type of fruits and vegetables each week to obtain the maximum benefit to your gut microbiota.
• Include polyphenols such as apples, berries, tea, olive oil which has been shown to increase the abundance of certain beneficial bacteria in your gut and promote anti-inflammatory properties in the body.
• Be mindful about your consumption of ultra-processed foods. These foods can be high in fat and sugar which can negatively affect and reduce your gut bacteria.
• Include fermented foods such as kimchi, kombucha, kefir in your diet to support your microbiome.
• Due to the gut brain axis, focusing on sleep and stress could also help with the functioning of the gut microbiota.

Do I need a probiotic supplement to support my gut microbiome?

Probiotic supplements are live microorganisms usually in a capsule or liquid form. These supplements are not essential for your gut health. There is limited clinical scientific research that suggests that taking these supplements can positively affect your health and in fact these could end up being a waste of money. Since there is a wide range of bacterial species it is still unclear as to which bacterial strains are most effective to support one’s gut microbiota. [5] Therefore, at this time, focusing on a diverse and varied diet is far more important and beneficial for your overall health and wellbeing.

References

1. Adak, A. & Khan, M. R. An insight into gut microbiota and its functionalities. Cellular and Molecular Life Sciences vol. 76 473–493 (2019).
2. Gentile, C. L. & Weir, T. L. The gut microbiota at the intersection of diet and human health. Science vol. 362 776–780 (2018).
3. Mayer, E. A., Tillisch, K. & Gupta, A. Gut/brain axis and the microbiota. Journal of Clinical Investigation vol. 125 926–938 (2015).
4. Sakkas, H. et al. Nutritional status and the influence of the vegan diet on the gut microbiota and human health. Medicina (Lithuania) vol. 56 (2020).
5. Mizock, B. A. Probiotics. Disease-a-Month vol. 61 259–290 (2015).