Understanding Probiotics and Prebiotics


If you’ve been keeping up with the latest health trends, you’ve probably heard the terms “probiotics” and “prebiotics” thrown around quite a lot. Though they might sound similar, they play different roles in our health.

By now, we know that within our gut lives an incredibly diverse and complex ecosystem of microbes which have a significant impact on our health, affecting everything from digestion and immunity1, to mental health2 as we’ve explored previously.

Probiotics are live bacteria and yeasts that are beneficial for your health, particularly your digestive system. They are often referred to as “good” or “friendly” bacteria because they help keep your gut healthy. They can be found in several fermented foods like yoghurt, sauerkraut, and kimchi, as well as dietary supplements. There’s a growing body of evidence suggesting that probiotics may help with conditions such as irritable bowel syndrome, inflammatory bowel disease, and even anxiety and depression3. The latter has even spurred research into the concept of ‘psychobiotics’ which may be a promising new approach for treating mental illness4. However, much more research is needed to fully understand the mechanisms through which probiotics can influence various biochemical and physiological processes, as well as determining the ideal dosage, treatment frequency, and duration for different probiotic strains (given the highly individualised nature of the gut microbiome)5.

While probiotics are the beneficial microbes themselves, prebiotics are the food that feeds them. They are types of dietary fibre that our bodies cannot digest, but our gut bacteria can6. Prebiotics are found in many fruits, vegetables, and whole grains, such as bananas, onions, garlic, asparagus, and oats. By consuming these foods, we’re essentially nourishing the beneficial bacteria in our gut which, in turn, produce many beneficial metabolites that are important for our health. More on that later!

Probiotics and prebiotics work best together, which is why they’re often referred to as “synbiotics”. When consumed together, they can interact in ways that boost their overall benefits. For instance, adding a dose of probiotics to your diet introduces beneficial bacteria to your gut. At the same time, consuming prebiotics ensures that these new inhabitants have the nutrients they need to thrive and multiply. Including them in your diet is a simple way to potentially improve your health. In a future post we will delve deeper into what we currently know about pro- and prebiotics for our mental health.

Please note that it’s a good idea to consult your healthcare provider before making any significant changes to your diet or before starting a new supplement regimen. They can provide personalised advice based on your health needs

Image credit: Christina Victoria Craft on Unsplash

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Foster JA, McVey Neufeld KA. Gut-brain axis: How the microbiome influences anxiety and depression. Trends in Neurosciences [Internet]. 2013;36(5):305–12. Available from: http://dx.doi.org/10.1016/j.tins.2013.01.005
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Misra S, Mohanty D. Psychobiotics: A new approach for treating mental illness? Critical Reviews in Food Science and Nutrition [Internet]. 2017;0(0):1–7. Available from: https://www.tandfonline.com/doi/full/10.1080/10408398.2017.1399860
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