Many people know kombucha tea for its health-promoting benefits. But is it actually good for you? Find out what we know (and don’t know) about the health effects of this popular fermented tea.

Once considered a relatively obscure health beverage, kombucha has gone mainstream.

Supermarkets and convenience stores around the world carry this type of tea. In 2017, sales reached more than $500 million in the U.S. alone. Food industry leaders predict global kombucha sales will be close to $2 billion by 2020.

Proponents have called it “the ultimate health drink” and the “tea of immortality.” Skeptics remain unconvinced. But what do we know?

What Is Kombucha Tea?

Kombucha is a sweetened, fermented tea.

The fermentation process creates, among other things, carbon dioxide (which gives the tea its fizz), alcohol. It also creates a variety of acids including acetic acid, lactic acid, propionic acid, glucuronic acid, and gluconic acid.

The taste of kombucha varies.