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The 3 K's: Fermented Drinks You Need in Your Fridge

We've got three words for you Kimmie: kombucha, kefir and kvass. What do they all have in common? They're gut-boosting, probiotic-packed fermented drinks. It's not all about yoghurt and sauerkraut - these tasty bevvies are your ticket to a happy gut. Here's why.

Fermented drinks have been cherished for centuries in various cultures worldwide, valued not only for their delicious flavours, but also for their impressive health benefits. Three stand out as gut-friendly powerhouses let’s unpack the unique qualities and wholesome goodness of these beverages that are a staple here at I Quit Sugar.



Kombucha is the wholefood world’s answer to soft drinks – bubbly, fizzy and tangy, this fun drink has it all. The difference? Kombucha is loaded with gut-loving, brain-boosting probiotics, so added a glass of the stuff to your day will actually benefit rather than hurt your health. This fermented tea drink, often referred to as the "Immortal Health Elixir," is made by combining sweetened black or green tea with a symbiotic colony of bacteria and yeast (SCOBY). As the SCOBY ferments the tea, it produces probiotics, organic acids, and enzymes that contribute to Kombucha's distinctive flavour profile and health benefits – the sugar also breaks down, ensuring you’re not hit with a blood-sugar crash later. Here’s why you’ll love this fermenting beverage:

  • Digestive aid: The organic acids in Kombucha, such as acetic acid, support digestion and may alleviate bloating and indigestion. Kombucha is a natural source of beneficial bacteria, which can help restore and maintain a healthy gut microbiome.
  • Detoxification: Kombucha contains antioxidants that aid in neutralising free radicals and promoting detoxification.
  • Subtly sweet: Kombucha may be the tastiest drink on the list – though that remains up for debate! – but that subtle sweetness and the strong tea flavour play a major role in the taste profile.

Now to find out what sets kombucha apart from the other drinks on the market – those powerful probiotics:

  • Acetobacter: This probiotic bacterium is responsible for converting ethanol produced during fermentation into acetic acid (vinegar). Acetobacter is commonly found in kombucha and contributes to its characteristic tangy flavour.
  • Gluconacetobacter kombuchae: A specific strain of Acetobacter commonly found in kombucha that plays a role in the fermentation process and the production of organic acids.
  • Lactobacillus: Certain Lactobacillus strains may be present in kombucha. Lactobacillus is a well-known probiotic group often found in fermented dairy products and contributes to the acidic and probiotic-rich environment of kombucha. 

Keen to make your own? We've got a simple, delicious recipe in our ALL NEW 21-Day Gut Rebalance Program.


Kefir is a fermented dairy drink (or non-dairy if the base is coconut milk) made by fermenting milk with kefir grains. Kefir grains consist of a combination of bacteria and yeast that create a creamy, probiotic-rich beverage with a tangy and slightly effervescent taste. While its lumpy texture may be off-putting to some, the benefits more than make up for it, with everything from anti-cancer properties to improved digestion on its resume, plus, Research shows that kefir grains can actually reduce the amount of “bad” cholesterol found in milk, making it a gut and heart-healthy drink. There’s also an extensive body of research finding kefir a potent anti-cancer agent. How? One study suggests that it delays the process of converting compounds into carcinogens by giving our immune system a heads up. Further research shows that it actually inhibited tumour growth – it’s worth noting that this was an animal study and we’ve still yet to learn more, but these findings are more than promising. Certain kefir strains have demonstrated antimicrobial properties, which may help inhibit the growth of harmful bacteria in the gut, instead encouraging the growth of the good guys. There’s also the added bonus that comes with most fermented foods and drinks – the process breaks down lactose and other compounds, increasing the bioavailability of nutrients like calcium, magnesium and other vitamins and minerals. Now, time to unpack those little bugs that make kefir so beneficial – the specific probiotics found in kefir can vary depending on the kefir grains used for fermentation, the fermentation process, and the type of milk or non-dairy base used, but there are a few common strains that are present in traditional dairy kefir:

  • Lactobacillus acidophilus: This is a well-known probiotic strain that is commonly found in fermented dairy products, and it’s known to improve gut health and improve lactose digestion.
  • Lactobacillus kefiri: The name probably gives away the fact that this strain is unique to kefir – it’s responsible for the fermentation process. It contributes to the characteristic taste and texture of kefir.
  • Lactobacillus casei: Another probiotic strain commonly found in fermented dairy products. L. casei has been associated with digestive health benefits.
  • Lactobacillus delbrueckii subsp. bulgaricus: Often used in yogurt fermentation, this probiotic strain may also be present in kefir and contributes to the fermentation process.
  • Streptococcus thermophilus: A probiotic strain that works in synergy with L. delbrueckii subsp. bulgaricus to ferment lactose and produce lactic acid.
  • Bifidobacterium species: Some kefir varieties may contain Bifidobacterium species, which are beneficial probiotics that can support gut health and immune function.


Kvass is a traditional fermented beverage originating from Eastern Europe. It is typically made by fermenting rye bread or beets with water, along with the addition of herbs and spices for added flavour complexity. During the fermentation process, beneficial bacteria and yeast are responsible for converting sugars into lactic acid and producing the characteristic tangy taste of kvass. While the specific probiotic strains in kvass may not be as extensively studied or well-defined as those in other fermented foods, some common probiotic bacteria that could potentially be present in kvass include:

  • Lactobacillus plantarum: This probiotic strain is commonly found in fermented foods and plays a crucial role in breaking down carbohydrates into lactic acid during fermentation.
  • Lactobacillus brevis: Another lactic acid bacteria that is known for its role in the fermentation process and can contribute to the sourness and probiotic content of kvass.
  • Leuconostoc mesenteroides: A probiotic bacterium commonly involved in vegetable fermentation and may be present in kvass made with beets or other vegetables.
  • Saccharomyces cerevisiae: This yeast strain is frequently found in fermented foods and is responsible for converting sugars into alcohol and carbon dioxide during the fermentation process. 

While kvass is still an impressive drink, it’s worth noting that its probiotic content may not be as significant as the others on this list. It does have a wide range of benefits though, from its antioxidant properties to its stress-reducing effects – beet kvass in particular is packed vitamin C and manganese.

Want to learn how to make homemade kombucha and a range of other fermented foods like yoghurt, sourdough and kimchi yourself? Or perhaps you’re keen to improve your gut health and reduce inflammation – the IQS team have something special for you. Our ALL NEW 21-Day Gut Rebalance Program kicks off soon with delicious, nourishing recipes and exclusive expert content to support you on your way to better health. Whether it's constipation, bloating or even stress that's got you down, it could be your gut warning you that you're missing out on the gut-nourishing foods that help us thrive. We'll show you the ins and outs of healing, from the benefits of probiotics and prebiotics to the inflammation-busting foods you should be eating. Take a look at some of the exciting new recipes on the program:

  • Pork Kimchi Dumplings
  • Homemade Sourdough Bread
  • Miso-Baked Salmon
  • Tempeh Satay
  • Chinese Beef + Broccoli
  • Chocolate Chia Smoothie Bowl

And that's not even scratching the surface! We're selling out fast so don't wait, sign up now!




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