Probiotics vs Fermented Foods


This content was made possible due to an unrestricted educational grant from Activia.

Fermented foods and probiotics are two areas that are very popular in the field of gut-health promotion. People often think fermented foods and probiotics are the same – but they differ in many important ways! Let’s break it down.  

First, what are probiotics?  

The Food and Agriculture Organization of the United Nations and World Health Organization (FAO/WHO) define probiotics as “live microorganisms which, when administered in adequate amounts confer a health benefit on the host.”1 In plain language, probiotics are “good bugs” or “good microbes” that improve certain aspects of our health. Each probiotic is unique, has a very specific intended purpose, with specific types or strains helping to manage certain specific conditions.2 These may include reducing antibiotic-associated diarrhea, managing IBS symptoms like bloating, and changes in bowel habits. These friendly microbes also help us digest fibre and other nutrients. 

Probiotics are known by their genus, species, sometimes subspecies, and strain. For example, for the probiotic bacterium Bifidobacterium animalis subsp. lactis CNCM I-2494, the genus is ‘Bifidobacterium’, the species is ‘animalis’, the subspecies is ‘lactis’ and the strain is ‘CNCM I-2494’.  

Contrary to what you may think, probiotics don’t make their way into your gut and set up ‘camp’ but rather, have a ‘transient’ effect meaning you consume them, they do a specific job, and then they leave your gut.  

It’s important to note that not everyone needs to take a probiotic for general “gut health”. Probiotics have been identified as a treatment for specific conditions and symptom relief. It’s important that you talk with your doctor, pharmacist, or dietitian before taking a probiotic, to ensure you have a proper diagnosis and understand how a probiotic may be helpful. Together, you can select an appropriate probiotic that is the most suitable for you. 

Probiotics come in various forms. Some come in pill form or powders, and they can also be found in certain foods! 

Now, what are fermented foods? 

Fermented foods are foods or beverages that are produced by controlled microbial growth.3 They include things like yogurt, kefir, sauerkraut, and miso, to name a few!  

It may come as a surprise, but fermented foods have been around for thousands of years! Although they were initially valued because of their long shelf life, and organoleptic properties (i.e. their taste and texture), research has also allowed us to understand their potential health benefits.4,5 

Consumption of fermented dairy foods such as yogurt have been scientifically studied. Health benefits include:6  

  • Improved ability to digest lactose 
  • Improvement in bone health 
  • Weight management 
  • Improvement in blood pressure 
  • Reduced risk of developing heart disease 
  • Reduced risk of developing type 2 diabetes 
  • Reduced risk of developing colon cancer 

Depending on the food, certain species of bacteria, yeasts and molds will carry out fermentation.  Microbes that carry out fermentation can still be alive in some fermented foods. However, other foods that undergo fermentation are then processed by pasteurization, smoking, baking, or filtering, which destroys the active microbes. 

Fermented foods that DO contain live microbes include:7 

  • Yogurt 
  • Kefir 
  • Uncooked sauerkraut 
  • Traditional Kimchi 

Fermented foods that DO NOT contain live microbes include:7  

  • Beer and wine 
  • Sourdough bread 
  • Chocolate  
  • Tempeh 

Do all fermented foods contain probiotics?  

The short answer is no.  Not all fermented foods use strains of microbes that have proven benefits for our health, or that can survive the trip through the gut. In addition, not all fermented foods have adequate amounts of those microbes to qualify as a probiotic!  

You can find a few fermented foods with probiotics on the market, like probiotic yogurt, however, you should check the label and read carefully. Products should display each strain’s designation, though some probiotics sold on the market may also use a simplified trademarked name instead. 

Check out our handy chart for reference:  

As you can see, fermented milks, such as some yogurts and kefir, contain probiotics. Still, as we mentioned earlier, not all fermented foods contain live cultures, and even if they do contain live cultures, these cultures may not meet the definition of a probiotic. In conclusion, you should always try to be informed about the fermented foods you are consuming and work with a health care professional if you are looking to add fermented foods to your diet to treat a specific ailment.  

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  1. Hill, C., Guarner, F., Reid, G., Gibson, G.R., Merenstein, D.J., Pot, B., Morelli, L., Canani, R.B., Flint, H.J., Salminen, S., Calder, P.C., & Sanders, M.E. (2014). The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic. Nature Reviews Gastroenterology & Hepatology, 11(8), 506-514.  
  1. Alliance for Education on Probiotics (AEProbio). (2021). Understanding probiotics. Retrieved March 6, 2021, from
  1. Dimidi, E., Cox, S.R., Rossi, M., & Whelan, K. (2019). Fermented foods: Definitions and characteristics, impact on the gut microbiota and effects on gastrointestinal health and disease. Nutrients, 11(8), 1806.    
  1. Melini, F., Melini, V., Luziatelli, F., Ficca, A.G., & Ruzzi, M. (2019). Health-promoting components in fermented foods: An up-to date systematic review. Nutrients, 11(5), 1189.  
  1. Kok, C.R., & Hutkins, R. (2018). Yogurt and other fermented foods as sources of health-promoting bacteria. Nutrition Reviews, 76(Suppl 1), 4-15.  
  1. Savaiano, D.A., & Hutkins, R.W. (2020). Yogurt, cultured fermented milk, and health: a systematic review. Nutrition Reviews, 79(5), 599-614.  
  1. Gut Microbiota for Health (GMFH). (2018). New Gut Microbiota for Health infographic on fermented foods and gut microbiota. Retrieved March 8, 2021 from