Kombucha is made by fermenting tea (usually black tea, although green tea is sometimes used) and sugar, together with a ‘symbiotic culture of bacteria and yeast’ (also called SCOBY). The SCOBY consists of live bacteria and yeast that ferment the sugars to produce a sweet, somewhat acidic, refreshing beverage. The process takes about 7 to 10 days, and afterwards the kombucha contains a mixture of sugar, polyphenols (from the tea), minerals, and vitamins.
Even though kombucha (known then as “Mo-Gu”) was a popular health tonic in China and Japan for hundreds of years, it was only really in the mid-1950s when it started gaining the attention of foreigners. It was first introduced to Russia (known by the trade name ‘Cainii kvass’, or ‘Kambucha’) and later into other European countries such as Germany, where it became known as ‘Heldenpilz’ or ‘Kombuchaschwamm’. It didn’t have super health food status back then, and was simply consumed as a fermented tea beverage.
But that all changed. Today, you can find kombucha in almost any store, and in a wide variety of flavors. You can even buy your own SCOBY at health shops. So, what about the reported health benefits? There are several claims stating kombucha can help with a list of ailments: improves digestion, boosts the immune system, reduces blood pressure, and even helps with rheumatism.
Despite all these claims (and several studies over the past decade), there’s a lack of evidence supporting them. Most of the evidence supporting any health benefits are anecdotal; that is, based on personal experience rather than research (i.e. replicated and controlled observations/experiments).
Kombucha is categorized as a fermented beverage, so the health claims you see are often tied to findings of other studies relating to the benefits of either fermented food on gut bacteria, or the health benefits of tea itself. Basically, people use the fact that it’s a fermented beverage, and assume that all health benefits that have been reported for fermented foods apply to Kombucha as well. And while scientists can’t prove any of these claims in the lab, the tea drinkers swear it alleviates their arthritis and regulates their appetites!
While there are no serious side effects to drinking kombucha, it’s advisable that you don’t go overboard. It still contains small amounts of caffeine (from the black tea) and alcohol (from the fermentation process), which eventually adds up if you drink too much. Another issue with kombucha, is the fact that it’s slightly acidic. This may damage your tooth enamel (in the same way sodas do) and stain your teeth. If you do drink it, dentists advise drinking it with a straw.
If you’re not sure whether kombucha is a good beverage choice for you, speak with your doctor first. It does contain live microorganisms, so if you are pregnant or have a health condition that compromises your immunity, it could do more harm than good.