All of this despite a (so-called) kombucha-related SCRAM debacle starring Lindsay Lohan, a well-publicized industry setback (in which some makers had to pull the stuff from shelves and reformulate it), oh, and a couple of reported deaths linked to the drink (but we’ll get to that later).
But first, a quick primer on what this stuff is. Kombucha isn’t a mushroom, despite popular belief. It’s a mixture of black tea, sugar, and SCOBY (symbiotic culture of bacteria and yeast). During fermentation, the yeast breaks down the sugar in the mixture. After seven to 10 days of fermentation, the drink contains organic acids, tea, vitamin, sugars, and minerals, and packs a sourish party-in-your-mouth punch that tastes a heck of a lot more exciting than water. Many mixtures are low in calories and sugars, making the drink an attractive alternative to juices and soft drinks.
But, is it really as healthy as people say? Is kombucha safe to home brew? And, what about those Kombucha-related deaths? We spoke to a few leading nutritionists to sort out the Kombucha story once and for all.
Though the maker of GT’s has credited kombucha with helping heal breast cancer, and others have claimed that kombucha helps with stimulating the immune system, hair growth, and other ailments, health experts agree that there is no scientific backing to support such claims. The American Cancer Society notes that no scientific evidence supports these health claims. (Dr. Andrew Weil and Mayo Clinic internist Dr. Brent A. Bauer have indicated similar positions.) Academy of Nutrition and Dietetics Spokesperson Andrea Giancoli, M.P.H., R.D., who specializes in healthful shopping and vegetarian eating concurs. “If you’re drinking kombucha because you think it’s going to cure cancer and fight all kinds of disease, it probably won’t," she says. "There’s really no evidence that it has any of these benefits yet.”
Though few studies have been completed on kombucha’s health benefits, a Cornell University study concluded that “Kombucha may be a healthful beverage in view of its anti-microbial activity against a range of pathogenic bacteria.”
The probiotics that most formulations include are also believed to help aid digestion. Giancoli says, “Research on probiotics is wide and varied. But, as far as research is concerned, the best evidence points towards better immunity and better digestive health, meaning you eliminate regularly and don’t get an upset stomach as much. For people with gastrointestinal problems, probiotics may help them feel better and may help alleviate some of those symptoms.”
However, both Giancoli and Dr. Daphne Miller, author of The Jungle Effect: Healthiest Diets From Around The World note that choosing different sources of these nutrients — for example, an unsweetened yogurt as a source of probiotics, protein and calcium, or fermented veggies such as sauerkraut, for obtaining lactobacillus and other beneficial bacteria — can serve as more nutritious options in the long run, as these options contain less sugar and empty calories.
Some formulations also include a bevy of B vitamins, some of which are known to be involved in energy release, according to Giancoli, while B12 and folate play a part in new cell synthesis. And, while many kombucha drinkers report a boost in energy after consuming these drinks, Miller notes that the bulk of the credit should go to kombucha's effervescence, alcohol, and caffeine content.
Finally, many brands also tout organic acids on their labels, but Giancoli notes that our bodies produce these acids on their own as part of our metabolism, and the jury is out as to whether we need additional supplementation.
According to beverage industry publication, BevNet, some kombucha makers question their competitor’s nutritional labeling, saying that that actual sugar levels, bacteria types, and number of organic acids included in the drink aren’t accurately reported. Others think that some companies’ brews secretly use forced carbonation. As of now, there isn’t even a legal definition of what constitutes “kombucha.”
Intra-industry bickering aside, our experts say that nutritional labels still serve as great guides when choosing which concoction to drink. And, as with most dietary choices, it’s important to read labels when buying kombucha. While some formulations are lower in sugar and calories than sodas, Miller says, “Many commercial formulations contain just as much sugar as your average soda.” Giancoli encourages us to observe calorie content as well, with some bottles packing 100 calories in an eight-ounce bottle.
While kombucha has been linked to a few deaths — in 1995, two women who shared the same kombucha starter died of cardiac arrest, for example — the bottled tea is safe for most people to consume. Though those worried about safety may want to steer away from home brews, according to Giancoli, who notes that the acidity of the drink can leach out metal compounds. (She cites a case in which home brewers used a ceramic pot with a lead in the glaze and contracted lead poisoning.)
“There’s potential for fungal contamination, lead poisoning, and bacteria contamination, all of which can make you ill,” she says. “If you’re going to drink kombucha, buy a pasteurized bottle, because that’s going to give you the lowest risk of contamination and the safest kombucha you’ll probably find.”
Researchers have also noted that molds can occur in homemade kombucha, which can produce toxic and carcinogenic mycotoxins. “Certainly there is the risk of mycotoxin contamination, especially in home brews, but a much larger risk is that you will drink empty calories,”Miller says.
Bottom line: “While kombucha is a tasty drink, it has no clear nutritional benefits," Miller says, adding, "I have seen many patients add a couple hundred liquid calories to their day by drinking it. For a refreshing drink consider unsweetened green tea or water with lemon instead."