Prebiotics vs probiotics, which one is right for your gut?

There is a new generation of smart foods, aimed at improving your health by targeting the microbes in your gut…enter Prebiotics and Probiotics. 

Every surface of your body, inside and out, is populated by microorganisms – mostly bacteria, but also fungi and viruses.  The inner linings of your gut, mouth, nose and genitals, for example, all contain vast communities of bacteria that live in a delicate equilibrium among themselves and with the cells of your body. Among these bacteria, those living in your gut, collectively known as the gut microbiota, have been shown to influence multiple aspects of health1.

Our diet, as well as the use of antibiotics or nutritional supplements, are all factors that influence the makeup of our gut microbiota, potentially influencing our path to health or disease2. For example, following a high-fat, high-sugar diet can lead to imbalances in the composition of gut bacteria, where one bacterial species overgrows – a condition called dysbiosis. Dysbiosis has been associated with a myriad of different health problems3-4. Hence, it pays to nourish and care for the health of our gut microbiota and an important factor to consider is diet5.

Nowadays, there are dozens of products available in supermarkets and health stores that claim to help your gut microbiota. Most of them claim to be concoctions of prebiotics or probiotics that will improve your health by targeting gut microbes. But, do these products really work? And which ones are right for you?

Probiotics: bugs for the gut

According to the World Health Organisation, probiotics are defined as: “live microorganisms” that, when administered in adequate amounts, confer a health benefit to the host”. Today, the term “probiotics” is commonly used as a label for any foods containing friendly microorganisms, usually bacteria, that are meant to provide some health benefits to the body.

Probiotics are naturally found in a range of popular foods, like some yoghurts, kombucha, fermented vegetables (think of kimchi, sauerkraut or pickles) and even in some types of cheese. Probiotics can also be obtained from certain supplements, but you should consult a physician before starting any regimen6.

  • Fermented Vegetables – Concoctions like Kimchi, pickled cucumbers
    or Sauerkraut has been consumed for years and are valued for their purported health benefits. At the time of consumption, these delicacies host a wide range of different bacteria, which can influence the composition of the host’s gut microbiota. Studies have established correlations between the consumption of fermented vegetables and protection against oxidative stress, toxicity, cancer, hypertension, immunity, and inflammation7-13.

    fermented foods

    Figure 1. Sample of fermented foods from local fermenter 66 Barrels.


  • Kombucha tea is an ancient drink, with multiple purported health benefits. Homemade Fermented Raw Kombucha Tea Ready to Drink Kombucha – this is a probiotic-based tea with a mild acidic taste. It is made by fermenting a sugary tea preparation (usually green or black tea) with a mixture of yeast and bacteria, called SCOBY. It is an ancient food icon, thought to have originated in China more than 2,000 years ago14 and extensively used today around the world.The fermentation process, led by the SCOBY, forms a complex concoction of organic acids, glucose, fructose, vitamins, minerals, amino acids and small traces of ethanol. Kombucha tea also contains polyphenols (originally found in the tea) and certain metabolites – chemicals generated by the fermentation process.


kombucha tea

Figure 2. Kombucha tea is an ancient drink, with multiple purported health benefits.
Homemade Fermented Raw Kombucha Tea Ready to Drink



Two recent reviews on the health benefits of kombucha tea found that this drink has antimicrobial, antioxidant, anti-cancer and anti-diabetic properties. One chemical in particular, called D-Saccharic acid-1,4-lactone or DSL, has shown great promise against cancer15-16.  However, studies on the health benefits of kombucha tea have, so far, been limited to animal models, so there is no clear evidence on their effects in humans.

  • Probiotic supplements – In recent years, scientists have developed nutritional supplements based on probiotics. These supplements are basically super concentrated mixtures of beneficial bacteria, aimed at improving the diversity and composition of gut microbiota. The most advanced forms of these supplements use a double wrapped capsule that helps with the delivery of the probiotics to the colon. Thus far, the use of these supplements has been shown effective against antibiotic‐associated diarrhea and inflammatory bowel disease13among other conditions

Prebiotics: food for your bugs

In contrast to probiotics, prebiotics do not contain any microbes. Prebiotics is the name given to foods that feed our gut microbiota. In fact, some prebiotic components, such as resistant starch, cannot be digested by the human body at all – they are fermented by the bacteria living in the colon. Bananas (especially green, unripe bananas) onions, garlic, lentils and other legumes, cooked and cooled pasta, are all sources of prebiotic fibre that feeds your gut bacteria.


probiotics vs prebiotics infographic

Figure 4. Prebiotics foods that contain certain types of fibre that are fermented by gut bacteria.

Prebiotics vs Probiotics: Food for thought


Figure 5. Foods containing resistant starch, including legumes and grains.

Given the amazing roles, gut microbes have in different aspects of our health, probiotics are a promising approach to consider. However, caution should be taken before using them, as some people could suffer adverse reactions from their use. For example, vulnerable groups, such as people with compromised immune systems or some pre-existing conditions can have an increased risk of infections when exposed to probiotics.

In contrast, consumption of foods rich in pre-biotics is, for most people, a risk-free practice, and one that is guaranteed to provide health benefits. However, be sure to consult with a nutritionist before embarking in a major change in your diet. This way you can ensure to follow an optimal diet that targets your specific nutritional needs.


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