Does kombucha shape up as the magic elixir of life that “wellness” gurus make out? Is it a “super food”? Dietitian Catherine Saxelby, who maintains the popular Foodwatch website, investigates.
Should you start making it at home? Is it something to add to your daily intake? The short answer is “not really”. If you want to add fermented food to your diet you’d be better off making your own sauerkraut which is quicker and easier to do. The long answer? Well, you MAY be getting some friendly bacteria to help your digestion or gut function but no-one knows for sure, and there is likely to be significant differences due to natural variations in the organisms used in the fermentation. There’s not a huge amount of research into Kombucha’s health benefits. To my way of thinking, its greatest advantage is its lower sugar content combined with its refreshment value as a tart, effervescent drink.
Kombucha is a slightly sweet, slightly acidic, fermented beverage based on tea, generally black tea but occasionally green or herbal tisanes. It is made from water, tea, sugar, bacteria and yeast. It’s a little fizzy which is refreshing and is drunk for its supposed health benefits which are mainly improved digestive balance and gut health from the bacteria you ingest. It’s been drunk for this health reason for centuries in Japan, China, Russia, Germany and the USA. It is obtained from an infusion of tea leaves with a SCOBY (which stands for a “Symbiotic Culture Of Bacteria and Yeast”). The fermentation by this “tea fungus” or “mother” is the process that ferments the sugar and yields acetic acid (which gives a characteristic sharp taste), carbonic acid, alcohol and carbon dioxide gas that adds the bubbles.
At around 1 per cent sugars, Kombucha is much lower in kilojoules/calories than other sweet drinks, such as juices (8–14 per cent) or iced teas (range 5–6 per cent). A half cup (125ml) of kombucha has 75kJ/18 calories while the same amount of iced lemon tea has 380kJ/90 calories. Of course, all this depends on what brand you buy or how you brew it. Devotees of kombucha claim it can stimulate the immune system, prevent cancer, improve digestion, prevent heart disease and boost liver function, claims similar to those made for vinegar. It may but it all depends on how you’ve brewed it. There’s scant scientific research to support these health claims. An excellent summary of the research can be found in a review in Comprehensive Reviews of Food Science and Food Safety. In it, Jayabalan et al sum up my thoughts nicely when they say: “Currently Kombucha is alternately praised as ‘the ultimate health drink’ or damned as ‘unsafe medicinal tea’. There are many conceptions and misconceptions regarding the health benefits and toxicity of Kombucha beverage. Though it is claimed to be beneficial for several medical ailments, very little or no clinical evidence is available for that.”
You can buy bottled kombucha, both pasteurized and unpasteurized, in various flavours everywhere from health food stores to supermarkets. The downside is that kombucha’s probiotics do not survive the pasteurization process, and drinking it unpasteurized, if it was not produced in sanitary conditions, may pose a food safety threat, especially for those who are pregnant or have compromised immune systems. So be careful where you buy it. And only buy it if it’s refrigerated.