Kombucha Tea: Health Tonic or Hoax?

An Enduring Beverage

Throughout the ages, cultures around the world have created fermented consumables as a means to preserve and enhance their food and drinks. Whether the end product is sauerkraut, kimchi, wine or cheese, fermentation has the ability to establish flavours and textures that surprise and tantalise the taste buds. One such cultured beverage is kombucha.

Thought to have been brewed in China perhaps as far back as the third century BCE, kombucha isn’t just some new health-food store craze. In Chinese, people refer to kombucha as hongchajun, chameijun and hongchagu. Often brewed in the summer, it’s typically served cold and is consumed after a meal to aid digestion and cleanse the palate. In Japan, the tea goes by the name kocha kinoko, which is not to be confused with another tea also called kombucha (tea made from the seaweed kombu). In Russia, people refer to the drink as chainyi grib, first making its way into publications during the second half of the 19th century and remaining a popular beverage until today.

Proponents tout the teas health properties,  asserting that kombucha can improve digestion, promote healthy skin and even prevent cancer. Although the drink does seem to have its benefits, some researchers claim that it’s nothing more than a fad, with no real evidence to back up the claims. Some studies have even found the drink to be dangerous under unregulated brewing conditions. With kombucha drinks becoming all the rage, and being expensive at that, do the benefits really outweigh the costs?

The Brewing Process

While kombucha does contain actual tea, it’s the added sugar and the help of bacteria and yeast that allows it to transform into a fizzy beverage full of body and tart flavour. The process itself is relatively simple, requiring only a large sanitized glass jar, healthy bacteria for starting the fermentation process, sugar, and tea. Of course, patience is also a necessary ingredient when brewing kombucha – it takes anywhere from seven days to a month to enjoy the finished product, depending on the carbonation or tartness you wish to achieve.

All in all, making the tea at home can be quite easy. First, infuse black, green or herbal tea with boiling water for approximately ten minutes. Then, dissolve white sugar into the mixture and allow it to cool down to room temperature. Next, add the SCOBY –  or symbiotic colony of bacteria and yeast – to the mix inside a sanitised wide-mouth glass jar. Also known as the “mother” or the “bacterial culture”, the SCOBY is the engine that gets the fermentation process going.

After adding some vinegar or pre-brewed kombucha to the batch, test the pH to keep any unwanted mold from growing on the tea. Lastly, cover the mixture with a cloth or thin dish towel. Leave the tea for about a week before measuring the pH levels and tasting for flavour. Should the pH level be too high, you’ll need to throw away the entire batch, for safety’s sake. To add some extra fizz, bottle the drink and leave them at room temperature to encourage further carbonation. Best enjoyed mixed with fruit and over ice, the finished product features a tangy, vinegary flavour that, although pungent at first, becomes more and more palatable to drink over time.

Health Claims

Fans of kombucha are eager to rattle off a list of reasons why they love their tangy tea. From aiding digestion to clearing up acne, the justifications for imbibing this tartly-flavoured fermented beverage are many. For starters, kombucha contains enzymes and live probiotic cultures which aid in digestion and in turn help the body to detoxify and cleanse. Plus for those watching their waistlines, the drink contains high levels of acetic acid and polyphenols which aid in weight loss.

Kombucha is rich in antioxidants, which the scientific community touts for their health benefits. Some claim that the antioxidants present in kombucha can help protect the liver from damage, even counteracting toxicity caused by carcinogens. They also work to control free radicals and thereby contribute to a stronger immune system. Packed with glucosamines, advocates assert that the drink prevents joint pain and preserves collagen in the body.

Advocates of kombucha’s health properties go as far as to assert that the beverage can halt the spread of cancer in the body, claiming that its high levels of glucaric acid can kill cancer cells. Also known as saccharic acid, the compound occurs naturally in grapefruit, apples, broccoli, Brussels sprouts and several other fruits and vegetables. A process known as glucuronidation is what destroys toxic chemicals and substances in the body and eliminates them through digestion. This process can, however, be reversed, releasing these same harmful substances back into the body. Responsible for this phenomenon is the enzyme beta-glucuronidase, a substance that none other than our friend glucaric acid elminates.

What we know about kombucha

So far, researchers have only tested the effects of glucaric acid on animals, but they have shown some promising results. In one study, scientists gave animals a glucaric acid supplement during the first and second stages of cancer, subsequently reducing tumour growth by 50%. Though that certainly is impressive,  scientists have never actually performed a test of the same calibre on humans.

Simply put, there isn’t enough trusted research to rely on. The human studies that have been performed come from individual case reports, which, according to Allison Dostal (PhD, RD) in her essay Keeping Up with Kombucha: Fact-checking the Fad, are some of the least trustworthy forms of scientific research. Of the studies that have actually been published, the outcome hasn’t been exceptionally positive.

Indeed, a number of trusted sources have even labeled kombucha harmful for consumption, including the Mayo Clinic. According to Dr. Brent A. Bauer:

“There have, however, been reports of adverse effects, such as stomach upset, infections and allergic reactions in kombucha tea drinkers. Kombucha tea is often brewed in homes under nonsterile conditions, making contamination likely. If ceramic pots are used for brewing, lead poisoning might be a concern — the acids in the tea may leach lead from the ceramic glaze.”

To be sure, contamination is possible when brewing kombucha at home, but it’s not exactly common, and even less likely when manufactured for public consumption. The question remains – is there some truth to what kombucha drinkers claim, or is it nothing more than snake oil?

Fact or fiction?

One has to ask – is the drink simply providing a placebo effect, or is there actually some benefit to its consumption? With so many kombucha fanatics out there, there must be at least some merit to drinking it. Years of anecdotal evidence support the claim that kombucha helps regulate digestion. Even former President Ronald Reagan claimed that it slowed the growth of his cancer.

As with most teas, kombucha contains beneficial antioxidants as well as live probiotics that help regulate gut function. Perhaps the reason scientists are not performing more human studies on kombucha is because there it’s something anyone can make, not just big corporations.  After all, you can make kombucha at home for pennies on the dollar unlike medications that need patents and laboratories.

Speculation aside, there’s no real harm in drinking kombucha, so long as you use sanitary brewing methods. With so many stories of it providing energy, improving digestion and even preventing disease, drinking it seems have positive effects. Besides, there are many who simply love the drink’s effervescence and pungent flavour. So why not try it out for yourself? The good news is that you can find kombucha in shops and restaurants around Australia, especially Sydney, Melbourne and Perth. No matter whether you brew it yourself at home or you purchase the drink from a health food store, kombucha’s flavour will either pleasantly surprise or revolt you.