The popularity of kombucha tea, a drink made from black tea and sugar that is fermented with bacterial and fungal cultures, continues to grow.
This craze is inexplicable to me. For despite the testimonials of such celebrities as Gwyneth Paltrow, Madonna, Halle Berry and Alex Baldwin, there’s absolutely no good scientific evidence to back up the long list of medicinal claims (everything from easing arthritis pain to smoothing out facial wrinkles) that have been made for this centuries-old Chinese concoction.
Just because something was used in antiquity, doesn’t make it healthful, folks.
Yet people keep drinking it. By the gallons, apparently. The New York Times reported earlier this year that U.S. sales of kombucha and other “functional” juices raked in $295 million for their manufacturers (which include big names like Coca-Cola) in 2009 — a 25 percent jump over sales two years earlier.
So what does science say about kombucha tea? Dr. Michele Berman, publisher of the Celebrity Diagnosis blog, reported yesterday on a literature review of kombucha that she and her husband and co-blogger, Dr. Mark Boguski, conducted at PubMed:
We … found 40 articles on kombucha tea. Many of these studies originated in China or India and consisted of testing the effects of kombucha tea on rats or mice; a few papers tested effects on human cancer cells in vitro. Some beneficial effects were seen but one study concluded that “[c]omparable effects and mechanisms in humans remain uncertain, as do health safety issues, because serious health problems and fatalities have been reported and attributed to drinking kombucha.
In other words, there have been no studies involving either the effectiveness or the safety of kombucha in actual human beings in a major medical journal. So any claims being made for the drink are untested and purely anecdotal.
Even alternative health guru Dr. Andrew Weil warns people away from the tea. “I don’t recommend kombucha tea at all,” he writes on his website. “I know of no scientific studies backing up the health claims made for it.”
The greatest danger from kombucha, says Berman, seems to come from brewing the tea at home — something that many Americans do, probably because they believe the drink is then more “authentic.” But these home-brewed versions can cause serious, even life-threatening, problems when they “become contaminated because of improper preparation and/or when kombucha interacts with alcohol or prescription drugs,” Berman points out.
Adverse effects, she adds, include “hepatitis, xerostomia [dry mouth], dizziness, nausea, vomiting, headache, shortness of breath, restless legs, abdominal pain, hypotension [abnormally low blood pressure], and tachycardia [racing heart beat]. In most cases, patients fully recovered after discontinuation of kombucha and symptomatic treatment. However there are case reports of serious and sometimes fatal cases of hepatic dysfunction and lactic acidosis.”
Back in the early 1990s, during the first wave of kombucha tea craze, an Iowa woman died of lactic acidosis and another became seriously ill after drinking home-brewed kombucha tea daily for two months. (At that time, the drink was being touted as a way of boosting the immune system, particularly in people with H.I.V. and AIDS.)
The CDC warned at the time that although “drinking this tea in quantities typically consumed (approximately 4 oz. daily) may not cause adverse effects in healthy persons … the potential health risks are unknown for those with preexisting health problems or those who drink excessive quantities of the tea.”
Whole Foods recently removed kombucha drinks from its stores because they were found to contain elevated levels of alcohol (a byproduct of the fermentation process). Although MinnPost is supposed to be a Lindsay Lohan-free space, I feel compelled to report Berman’s observation that this may explain why the actress’ alcohol-monitoring bracelet became activated after she had been ordered by the court to refrain from drinking alcoholic beverages.
Yes, Lohan attests to the health wonders of kombucha tea, too.