A. Taylor Viggiano, an intern at Tufts’ Human Nutrition Research Center on Aging, responds: “Tangy, tart and ever so sweet, kombucha tea is an increasingly popular fermented tea drink. Kombucha is a mixture of tea and sugar fermented through the symbiosis of acetic acid bacteria and various fungi. The name ‘kombucha’ is a combination of Kombu, the Korean doctor who introduced this potion, and ‘cha,’ the Japanese word for tea. In the year 414, Dr. Kombu took this tea to Japan to cure the emperor’s gastrointestinal woes. Subsequently, this tea was popularized in Russia after its introduction by Asian merchants and then made its way into Europe.
“While kombucha has been produced for centuries elsewhere, it has only recently attracted attention in the US as a potential defense against cancer, various cardiovascular diseases and digestive problems. Experimental studies done predominantly in animals have revealed that kombucha does indeed contain bioactive compounds that have important properties including antioxidation and enhancement of immunity. This may make kombucha an appealing functional food when brewed safely and consumed responsibly.
“But the medical literature, including reports from the Center for Disease Control and Prevention, includes a few case studies of individuals who experienced serious illnesses and at least one fatality after consumption of home-brewed kombucha. Effects include metabolic acidosis and blood-clotting disorders. This is thought to have been due to toxic elements in the particular strain of fungus/mushroom.
“In summary, human research on kombucha is limited and lacks any clinical trials. So the takeaway is this: If you enjoy the uniquely strong flavor of kombucha and consume it in moderation, it may carry some potential health benefits; however, you should be careful to ingest only commercially produced kombucha.”