Probiotics vs. prebiotics: What’s the difference?

It may sound a bit unappetizing, but the human gut is home to trillions of bacteria. These microscopic bacteria play a crucial role in keeping us healthy, whether by helping us process food or contributing to our mood and behavior. To help keep our gut bacteria healthier, there are two key things we can do – consuming foods rich in prebiotics to help the bacteria already in our system and adding more with probiotics.   

It can be difficult to keep the difference between prebiotics and probiotics straight. While they may share similar names, their functions within our bodies are quite distinct.  

Prebiotics can be thought of as fertilizers for our gut bacteria. Prebiotics are non-digestible food components, like plant fibers, that promote the growth of healthy gut bacteria. Prebiotics help the bacteria already in your gut grow by giving them something they like to eat, which in turn allows our bodies to create healthy bacteria and helps enhance our overall health. 

You can consume prebiotics from a wide range of fruits and vegetables, but most commonly, prebiotics are found in bananas, onions and garlic. 


  • Bananas
  • Onions
  • Garlic
  • Leeks
  • Asparagus
  • Oats

Probiotics are different from prebiotics in that they contain live microorganisms that, when consumed directly, add new live bacteria straight into your gut. Probiotics are found in a variety of foods, but most commonly in yogurt. 

When looking to add yogurt into your diet, be sure to check the label to make sure it includes “live and active cultures.” 

In addition, fermented foods, such as sauerkraut or kimchi, are some of the best sources of probiotics, as the fermentation process creates an environment that promotes the growth of various species of good bacteria. 


  • Yogurt
  • Sauerkraut
  • Kombucha
  • Kimchi
  • Pickles
  • Sourdough bread

As more people look to add both pre- and probiotics to their diet, you may notice an increase in supplements at the grocery store or pharmacy. Given the wide variety of bacteria available in each supplement, it is best to consult a doctor or dietitian to understand which type of supplement may be best for you. 

Currently there are no recommended daily intake guidelines for prebiotics or probiotics. However, many suggest adding as many foods rich in prebiotics and probiotics into your diet as possible. 

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