Fermented Foods: What Are They & Should I Be Eating Them?

Fermented foods seem to be all the rage. From yoghurt, a common household staple, to kombucha and sauerkraut which are currently making a statement on supermarket shelves. But what exactly are fermented foods? And should you be including them in your diet? Keep reading to find out.

What are Fermented Foods?

Fermentation is an ancient process that occurs when microbes (bacteria and yeast) break down the sugars in foods. This process changes the taste, texture, and nutritional profile of foods. Fermentation is most commonly used to preserve foods and make foods easier to digest. Some fermented foods contain live microbes when we digest them, including probiotics.

Are they good for you?

There are many strains of bacteria present in fermented foods, including probiotics, which are particularly beneficial for our health. When consumed, these bacteria can synthesise vitamins, produce enzymes to aid digestion, and can help crowd out the bad bacteria in our gut) (1)( 2).

Not all commercial foods will contain live probiotics when you consume them due to heating processes, such as wine, canned vegetables, and sourdough bread. However, certain items, still retain some beneficial properties, for example, the fermentation process does make sourdough easier to digest for some people compared to regular bread.

Although more research is needed to confirm specific health benefits of fermented foods, promising findings are showing associations between fermented food and improved immune system health, gut health, and improvement on diseases such as irritable bowel syndrome, diabetes and heart disease (3).

How much should I eat?

As the research is still growing around fermented foods, there is no conclusive recommended serving size or daily serves. However, 1-3 servings/day can be considered a common sense amount.

Keep in mind that fermented foods can contain salt or sugar, for example, sauerkraut and kimchi are high in sodium (salt) and kombucha does contain added sugar- so it’s important to be mindful of this.

If you’re not used to eating fermented foods, you may experience symptoms at first such as bloating and gas. It will be helpful to start with a small amount and work your way up.  One tablespoon of sauerkraut per day is a great start.

How can I eat fermented foods?

It may be easier than you think to get in your daily dose of fermented foods. Here are some ways to spice up your current diet with fermented foods

  • Add fermented vegetables such as pickles, kimchi, and sauerkraut to your sandwiches, salads, or as a side dish
  • Try out sourdough bread for your sandwiches
  • Eat cheeses high in probiotics, including Gouda, mozzarella, cheddar, and cottage cheese
  • Add some Greek yoghurt to your breakfast or eat it as a snack
  • Add tempeh (fermented soybeans) as a protein in meals
  • Swap out sodas for kombucha or kefir as a drink
  • Using miso to flavour your soups

A final word

The evidence on fermented food is promising but still growing, however, they do appear to make a great addition to an overall healthy diet. Getting plenty of prebiotic fibre (that is, the food that feeds the good bacteria in your gut) is still the key to good gut health. You can do this by eating a variety of fruits, vegetables, whole grains, legumes, nuts, seeds.

If you are having ongoing gut issues, speak to your GP, dietitian or gastroenterologist as adding probiotics and fermented foods may sometimes make the situation worse.

Want to try out a quick, affordable recipe with only two ingredients?

Canned sauerkraut at the supermarket can be expensive. So, a more affordable and healthier option may be to make your own at home. You could even make large batches which can be kept refrigerated for up to 6 months.

Homemade Sauerkraut


  • 1 whole cabbage (approx 1kg)
  • 20g non-iodised salt (20 grams of salt for every 1kg of cabbage)


  • Remove outer leaves of cabbage and save to use later.
  • Cut the cabbage into eight wedges and remove just the very centre hardcore.
  • Slice each cabbage wedge crossways into thin slices and place in a large bowl.
  • Add the salt to the sliced cabbage and massage the cabbage firmly for about 5 minutes.
  • Cover the bowl with a cloth and set it aside for an hour or so.
  • After an hour, massage the cabbage again to help draw out the liquid.
  • Pack the sliced cabbage and liquid into clean, wide-necked jars about 1 litre in size.
  • Place the reserved outer cabbage leaves on top of the sliced cabbage. Press it down well then place a weight inside the jar to keep the cabbage submerged below the liquid. (Note: liquid should cover the cabbage at all times. If it evaporates add some more salted water)
  • Cover jars with a cloth and leave in a cool, but not cold, place out of the sun for at least a week or until sauerkraut tastes right. This can take up to a month depending on how cold the room is.
  • Once the sauerkraut has fermented to your liking, remove any white scum and then place the lid on the jar.

Recipe Love Food Hate Waste



  1. Şanlier, N., Gökcen, B & Sezgin, A. (2019). Health benefits of fermented foods. Critical Reviews in Food Science and Nutrition,59:3,506-527. DOI:
  2. Dimidi, E., Cox, S., Rossi, M., Whelan, K. Fermented Foods: Definitions and Characteristics, Impact on the Gut Microbiota and Effects on Gastrointestinal Health and Disease. (2019). Nutrients, 11(8):1806
  3. Rapson, J. (2018). Fermented foods: the latest trend. Retrieved from

Coyle, P. (2020). What Is Fermentation? The Lowdown on Fermented Foods. Retrieved from

Glassman, K. (2020). Why Is Sauerkraut Good for Me? Retrieved from

Harvard Health Publishing. (2021). Fermented foods can add depth to your diet. Retrieved from

Mcmillen, M. (2017).  Could Fermented Foods Boost Your Health? Retrieved from

Chilton, S. N., Burton, J. P., & Reid, G. (2015). Inclusion of fermented foods in food guides around the world. Nutrients, 7(1), 390–404

Last modified: July 15, 2022