Kombucha tea is made by fermenting several species of yeasts and bacteria along with sugar in black tea. The colony of yeast and bacteria is called a kombucha mushroom, although it is not actually a mushroom. The resulting tea has been promoted as a panacea for serious conditions such as cancer, autoimmune disorders and aging, however there is no scientific evidence for these claims. There is, however, evidence for serious side effects of kombucha tea, including death.
There have been many reports of severe acidosis, which is a life-threatening condition caused by an abnormally high amount of acid in the body, in people who had recently consumed kombucha tea. In 1995, the Centers for Disease Control and Prevention reported that two women were hospitalized with severe acidosis after drinking kombucha tea that they had made daily for two months. One of the women died, and the other’s heart stopped but she recovered. A 22-year-old HIV-positive male presented with lactic acidosis and died within 15 hours of drinking kombucha, as reported in a 2009 "Journal of Intensive Care Medicine."
Liver damage is another side-effect associated with drinking kombucha. Although complete liver failure resulting in death is rare, it is not impossible. The 22-year-old who developed acidosis and died shortly after consuming kombucha tea also went into liver failure. More commonly, according to the American Cancer Society, liver damage occurs in kombucha drinkers as jaundice. As jaundice sets in, your skin starts to turn yellow, often followed by your eyes and nails.
Lead poisoning is another risk of kombucha consumption, because of the way the tea is often made. According to the American Cancer Society, if the tea is brewed in a pot containing ceramic, lead crystal or paint, the acidic tea will absorb toxic lead from the pot. Lead poisoning has a wide variety of symptoms and is difficult to diagnose, so you should contact a physician immediately if you suspect you may have been exposed to lead.