Do fermented foods contain probiotics?

Kimchi is a fermented food that does contain live cultures when bought fresh.

Fermented foods and drinks have been growing in popularity for years. Just look at your supermarket shelves where you can easily find kimchi, kombucha, and kefir. The increased interest in fermented foods is largely due to their perceived health benefits as people seek to consume more gut friendly probiotics. 

But did you know, many fermented products do not actually contain probiotics. 

What are fermented foods?

Fermented foods and drinks are made using the growth of live microbes such as bacteria, yeast, and mould. The live microbes are fed sugars in the form of milk, vegetables, legumes, or wheat, which they ferment to create gases, acids, or alcohols. This gives the food product a unique taste, texture, and aroma. Examples of fermented foods include sourdough bread, tempeh, sauerkraut, yoghurt, cheese, and kimchi. 

Some fermented foods have these live microbes present when we eat them, such as yoghurt and kefir. These live microbes are called ‘live cultures’. However, other fermented foods require pasteurisation or heat-treatment to make them safe to consume and sell on supermarket shelves. This high heat destroys the live microbes in the final product. Foods that do not contain live microbes include sourdough bread, commercial kombucha, and jars of kimchi or sauerkraut sold at room temperature. 

To increase your chance of consuming a fermented food product with live microbes present, choose fermented food that are sold in cold-storage and look for the term “live cultures” on the label. Some fermented foods have probiotics or live cultures added to them after fermentation. You can look for this on the ingredients and nutrition panel.


Yoghurt label with arrow pointing to live cultures

Live cultures VS probiotics

While fermented foods can contain ‘live cultures’ these are not the same as probiotics. 

Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit to the host” (ISAAP). Basically, for something to be defined as a probiotic we need to know the name of the microbes present, the amount of microbes present, and there must be good evidence for their health benefit. 

You can look at probiotics like medicine. When you are sick you want to take the right type and dose of medicine to improve your health. And to get specific benefits from probiotics, you must take the correct strain and dose for your health concern. A dietitian can help you choose the right probiotic.

When it comes to fermented foods, every batch contains different amounts and types of microbes. To say a product contains probiotics, manufacturers would need to be able to guarantee you are getting the right strain of probiotic at the correct dose. This would require the manufacturer to test every batch of product which would be expensive and time consuming! Instead, we say these foods contain live cultures which do not need to have proven health benefits. 

So, should you bother consuming fermented food if they don’t even contain probiotics?

Yes! While more research is needed, fermented foods have been associated with positive health outcomes. For example, daily consumption of fermented dairy such as yoghurt, kefir, and cheese has been linked with reduced risk of type 2 diabetes and cardiovascular disease. Fermentation also reduces the lactose present in dairy products, making them appropriate for people with a lactose intolerance. Kimchi has been linked with a reduced risk of type 2 diabetes, and tempeh is associated with lower cholesterol levels.

Unfortunately we do not know if these health benefits are due to the live cultures or due to other nutrients present in the food. More research into this area is required.

Sourdough bread is a fermented food but it does not contain live cultures or probiotics

Should you pick fermented food or probiotics?

It depends.

Fermented foods like yoghurt, kefir, cold-storage sauerkraut and kimchi, tempeh and cheese are a great way to consume potentially beneficial live cultures. They are also associated with lowering our risk of type 2 diabetes and cardiovascular disease. Fermented foods are easy to access and taste delicious. Regularly consuming fermented food in your diet will provide general nutrition and health benefits.

Probiotics are not required for good health but they can be used to address a specific health concern. For example, to reduce the risk of traveller’s diarrhoea or to manage bloating. It is important to pick the correct strain and dose of the probiotic for the issue you are hoping to address. There is a lot of false advertising when it comes to probiotics, so it is recommended to choose a trusted brand. A dietitian can provide advice on this. It is important to note that probiotics should be used alongside other therapies and management strategies. 

If you want to best of both worlds, you can always choose a fermented product with added probiotics. This is particularly common with yoghurt and kefir products such as Activia or Vaalia. But again, probiotics are not necessary for a health diet. 

If you want personal advice around how fermented foods and probiotics can benefit your health, Kim offers personalised nutrition consultations. Find out more here.


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