The Low Down On Probiotic, Cultured and Fermented Foods

There is no denying that optimising one’s gut health is now deemed one of the most important aspects when it comes to healthy eating. The first thing to note however, is that there are many every day wholefoods that have been studied and shown to be best for gut health which include: vegetables, fruits, legumes, wholegrains, extra virgin olive oil, yoghurt, nuts, seeds and fish.

There are also some foods and supplements that are now in the ‘gut health’ category and you will see these listed as probiotic, cultured or fermented foods/products. So what is the difference and which should we be using?   

Fermenting food is a process that has been around for thousands of years and was useful for preserving foods and extending their shelf life. It is still useful for this purpose but there is now more emphasis on the nutritional value, and in particular the benefits on gut health from fermentation. Fermenting a food is a controlled anaerobic process where microorganisms like bacteria and yeast break down food components, such as sugars, and produce beneficial metabolites as a result (more bacteria, organic acids, peptides, vitamins, gases and alcohol etc).

Fermentation can happen with or without the use of cultures (microorganisms like bacteria and yeast) which basically ‘kick-off’ the fermentation process. For example kefir uses a starter culture where as kim chi does not. Therefore when you hear ‘cultured food’ it really means fermented using a starter culture.       

fermented veg000003.JPG

Fermentation produces probiotics so many fermented foods contain probiotics. In short, probiotics are considered ‘beneficial bacteria’. For example kefir is a fermented milk drink and the fermentation process (when bacteria and yeast from the kefir starter culture break down the lactose in the milk), produces a number of beneficial probiotic bacteria. On the other hand some fermented foods, for example fermented vegetables like kim chi and sauerkraut may not necessarily contain probiotics at the time of consumption because the fermentation process has already happened, but the fermentation itself produces metabolites that are beneficial for our gut health (organic acids, peptides, vitamins etc).    

Not all fermented foods are created equal however. Some fermented foods have been pasteurised so that they can be stored on the shelf at room temperature, however, this process kills off any live beneficial bacteria. Therefore when looking for a good fermented product you want it to be naturally fermented and it should be stored in the refrigerator.

Probiotics come in many different strains and species and these are not only contained in fermented foods but can also be purchased as a supplement. Different probiotic supplements contain single or a combination of strains of bacteria and these can be a multi strain probiotic to have more general benefits or can be more specific strains to have more specific benefits (ie. reducing IBS symptoms).      

Probiotic supplements contain probiotics at therapeutic levels. This means that is the level known/required to exert their associated benefits to the host. Fermented foods on the other hand, may not contain a therapeutic dose of probiotics (aside from kefir) but do still contain some probiotics, plus the aforementioned beneficial metabolites produced from the fermentation process.

Taking a supplement alone will not work wonders for your gut health because wholefoods are what the bacteria in the supplements need to thrive so a wholefood diet is essential regardless.

My favourite fermented foods are: Kefir and kim chi, followed by yoghurt, sauerkraut, miso, tempeh and kombucha.