What’s the difference between fermented foods and probiotics?

What are fermented foods?

Fermented foods like sauerkraut, sourdough, kimchi, yoghurt and kombucha are food and drinks that have been fermented by bacteria and yeasts. Fermentation is the digestion of the microbial world, and involves the transformation of natural sugars in food into lactic acid, ethanol and carbon dioxide. This gives these foods their distinct characteristics, such as the sourness of sauerkraut and yoghurt, and the carbonated bubbles in kombucha. If not heat treated, these foods will be teeming with microbial life and as such are often termed as ‘probiotic’ foods and are celebrated as gut health heroes. However, these foods are often not true probiotics...

What is a probiotic then?

For a food or supplement to be called a probiotic, it has to have clinical research that shows the specific strains that were used to manufacture them have proven health benefits.

Many fermented foods don’t specify the exact strains of bacteria or yeast used during the fermentation process and therefore cannot be called a probiotic according to international standards. They contain a generic mixture of various microorganisms which are capable of fermentation, and are safe for consumption at unspecified levels. However, these non-harmful living bacteria found in fermented foods are not necessarily beneficial probiotic bacteria that will tangibly improve your health.

Different strains of bacteria can be as different as a human and a lemur, so it’s incredibly important to know what strains you are consuming so that you know what beneficial effects they will have on your health (if any at all).

Putting it all together

A good quality probiotic supplement will contain specific probiotic strains which have been shown to address a health concern and provide a health benefit through clinical research in humans. These specific strains are then carefully cultured and packaged to deliver a certain amount with every dose so that these health benefits can be felt by the people taking them. People taking a good probiotic supplement can guarantee they’re taking the right strain at the right amount needed to have a certain health benefit.

So, if you’re looking to improve your gut health and reduce inflammation, use a probiotic supplement with specific strains proven to do just that, such as Lactobacillus plantarum 6595 or Lactobacillus rhamnosus GG.

While fermented foods can be part of a healthy balanced diet, eating them in the hope of repairing years’ worth of poor gut health is not an evidence-based strategy*. It’s akin to playing a game of roulette, buying a lottery ticket, or having a lucky dip.

So if you’re trying to achieve a certain health outcome by focusing on your gut health, be more selective in the choice of your ‘probiotics’ and choose supplements (or foods if you can find any) which contain clinically proven probiotic strains.

*Some commercially available yoghurts meet this probiotic criteria, and will list the specific strains used in the fermentation process which is great! But many don’t.