Probiotic drinks like kombucha tea are one of the hottest trends in health and nutrition. Once thought of as something your hippie aunt brewed on her kitchen counter, you can now find all different flavours of kombucha in traditional grocery stores, health food stores and even at farmers’ markets and craft breweries. Why on Earth would anyone want a drink made from a starter combination that resembles a gelatinous mushroom? Well, actually it’s tangy, refreshing and pretty good for you, too.
Fermented foods and drinks have been a part of global food culture for at least 6,000 years1,2. Some of your favourite foods are fermented or cultured by helpful bacteria and yeasts. Think of beer, wine, cheese, yoghurt, sauerkraut, tempeh, kimchi and even some pickles. Kombucha tea is usually made by taking black or green tea and adding a starter culture to it comprised of yeasts and bacteria. The beverage is then allowed to slowly ferment at room temperature for seven to 10 days.
While that may not sound appealing, certain bacteria and yeasts are extremely important to the overall health and function of our gastrointestinal system6. The gastrointestinal (GI) tract is the first line of your immune defense system. It’s important to do everything possible to help the good bacteria proliferate and keep the bad ones to a minimum. The term “gut microbiome” refers to the trillions of microbes that colonize our GI tract. Research on the gut microbiome is exciting, and we are only beginning to understand the tip of the iceberg. Those little bugs play a role in immune function, weight management, protection from disease and the development of autoimmune conditions, and even mental health. The gut-brain connection is a very real thing.
Potential health effects of kombucha tea:
While research on humans is still in its early stages, there does seem to be evidence that kombucha tea can have antioxidant effects and may help provide some protection against infection6. The majority of evidence points to positive effects on the immune system2,3,4,6, which makes sense considering that fermented foods are known to boost immune function. Kombucha tea is thought to contribute beneficial bacteria to the gut microbiome.
If you want to foster a healthy gut microbiome, there are other ways besides just fermented foods. We now know that people who eat more plant-based diets have a healthier microbiome than those who eat a typical Western diet comprised of mostly meat, cheese and refined grains7,8. This may be one factor in longevity, easier weight management and prevention of disease. The fibre in fruits, veggies and whole grains like oats make the good microbes really happy. Certain fibres in plants are considered prebiotics, or food for the probiotics. Classifying microorganisms as “good” or “bad” is overly simplistic, but we do know that creating an environment for certain types to flourish can have a significant impact on human health.
When dealing with live active microbes and yeasts, food safety becomes extra important. Kombucha should smell and taste tangy, fresh and a little vinegary. The color of unflavored kombucha is usually gold, tan or light brown. If you ever see mold, black or green spots or smell something cheesy or rancid, please discard it and definitely don’t drink it. If considering drinking home-brewed kombucha, be sure it was made under ultra-sanitary conditions, as home-brewed is at higher risk for accidental contamination, and, as with anything, don’t go overboard. There are documented cases in which people became quite sick from consumption of kombucha5. Personally, I prefer to buy commercially prepared, especially if giving it to children or anyone immunocompromised, and I only drink it in moderation.
By Emily C. Harrison MS, RD, LD of Nutrition for Great Performances.
Emily Cook Harrison MS, RD, LD
Emily is a registered dietitian and holds both a bachelor’s and master’s degree in nutrition from Georgia State University, USA. Her master’s thesis research was on elite level ballet dancers and nutrition and she has experience providing nutrition services for weight management, sports nutrition, disordered eating, disease prevention, and food allergies. Emily was a professional dancer for eleven years with the Atlanta Ballet and several other companies. She is a dance educator and the mother of two young children. She now runs the Centre for Dance Nutrition and Healthy Lifestyles. She can be reached at firstname.lastname@example.org, www.dancernutrition.com
1. Chambers PJ, Pretorius IS. Fermenting knowledge: the history of winemaking, science and yeast Research. EMBO Reports 2010.
2. Foroutan R. Food and Nutrition Magazine: The history and health benefits of fermented foods. Winter 2012.
3. Cetojevic-Simin DD, Bogdanovic GM, Cvetkovic DD, Velicanski AS. Antiproliferative and antimicrobial activity of traditional Kombucha and Satureja montana L. Kombucha. J BUON. 2008 Jul-Sep;13(3):395-401.
4. Vīna Ilmāra, Semjonovs Pāvels, Linde Raimonds, and Deniņa Ilze. Current Evidence on Physiological Activity and Expected Health Effects of Kombucha Fermented Beverage Journal of Medicinal Food. February 2014, 17(2): 179-188. doi:10.1089/jmf.2013.0031.
6. Vina I, et al. Current evidence on physiological activity and expected health effects of kombucha fermented beverage. J Med Food. 2014 Feb;17(2):179-88. doi: 10.1089/jmf.2013.0031.
7. The Health Advantage of a Vegan Diet: Exploring the Gut Microbiota Connection
8. Doucleff M. Chowing Down On Meat, Dairy Alters Gut Bacteria A Lot, And Quickly.
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