Fermented Foods – what are they and why are they good for you?

Welcome to the final installment of the Challenge Me Fitness blog series on gut health by our resident nutritionist Elle Eastwood. This week we are talking all things fermented. You can’t really step foot in a health food store without seeing a multitude of fermented foods. Pretty, rainbow coloured cabbage or ‘sauerkraut’ fill the fridges and strange names that all seem to involve the letter ‘ k’, like ‘kombucha’ and ‘kefir’ line the shelves. So are these fermented foods full of magical, super gut healing powers or are they just pretty, overpriced jars?



Fermentation is the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat. Fermentation isn’t a new thing. It’s actually one of the oldest types of food preservation techniques in the world and is believed to date back to at least 5000 BC!  When foods undergo fermentation, bacterial microorganisms convert starches and sugar into lactic acids. It is this process which dramatically increases the nutritional value of the food and creates probiotics, live bacteria that are good for your digestive system. While scientists don’t know exactly how probiotics work, they have been proven in numerous studies to improve symptoms in those with gut problems as well as provide protection from infection and help to regulate metabolism. As a bonus, fermentation also preserves the life of food and enhances its flavour considerably.

Fermented foods normally come in dairy and vegetable origins, with the most common being yoghurt, sauerkraut and kimchi. You’ve probably also heard of kombucha, a fermented tea containing probiotics.



Fermentation enhances the nutritional content and digestibility of the food. It is also largely celebrated because it turns these foods into little probiotic powerhouses. As a result, consuming fermented foods is often encouraged to promote gastrointestinal health.

Examples of fermented foods and their nutritional benefits include:

Sauerkraut (fermented cabbage) & Kimchi (Korean dish of spicy pickled cabbage)

  • The vitamin C content can increase by up to 600% after seven days of fermentation.
  • Has a low glycemic index after fermentation process
  • Is rich in L.plantarum probiotic strains
  • Contains anti-fungal compounds

 Kefir (fermented milk drink)

  • Improves cholesterol metabolism
  • May reduce severity of giardia infections
  • May improve gastric acid & pancreatic enzyme secretion

Kombucha (fermented tea)

  • Studies demonstrate favourable effects on cholesterol metabolism
  • Contains an array of organic acids shown to have antioxidant effects (repairs cell damage)
  • May reduce blood glucose levels
  • Has shown promise in aiding stomach ulcers


So there is merit to the marketing madness after all. Fermenting foods starts with relatively simple foods and turns them into little nutritional powerhouses. What’s doubly wonderful, is so many of them can be made from home for very little cost. Happy fermenting x

If you want to try making your own sauerkraut at home, check out this video for a step by step guide.


A little naturopathic side note: I would like to point out that like any good thing, fermented foods are not the be all and end all. If you have (or suspect) you have gut dysbiosis issues, it’s best not to be consuming excessive amounts  of fermented foods as they are widely grown bacteria which can provide a medium for growth for pathogenic organisms. You don’t always know what bacterial species you are feeding in the gut, so you if are on a gut healing protocol, it’s best to reintroduce fermented foods back into the gut slowly. Always consult your practitioner if in doubt.



Aloulou, A et al. 2012,’ Hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats’, BMC Complementary & Alternative Medicine, vol. 12, no. 63, <https://www.ncbi.nlm.nih.gov/pubmed/22591682>

Bellassoued, K et al 2014, ‘Protective effect of kombucha on rats fed a hypercholesterolemic diet is mediated by its antioxidant activity’, Pharmaceutical Biology, vol. 53, no. 11,

Bourrie, B et al. 2016, ‘The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir’, Frontiers in Microbiology, vol. 7, no. 647

Hawrelak, J 2013, ‘The Natural Gastrointestinal Masterclass: Session Two: Fermented Foods, Prebiotics, Synbiotics & Colonic Foods’


Elle Eastwood is a naturopath and nutritionist (BHSc) who first entered the world of complementary medicine after her own childhood journey with ulcerative colitis. Her experience of managing a chronic condition from a young age gave her a first hand insight into navigating an autoimmune disease diagnosis. Elle is committed to providing holistic treatment tailored to each individual’s unique needs. Ultimately, her goal is for patients to walk away from a consultation feeling happier and healthier!

Elle is also a kiwi, cheese lover and chronic tea drinker.