One of the unusual things about kombucha is the fact that it’s fermented. Outside of sauerkraut or pickles, it’s hard to imagine many foods in a modern diet that are fermented.

We haven’t needed to ferment foods since the advent of refrigeration, which has changed diets and changed tastes. However, it’s a part of our food history that’s little-recognized:

every long-lived culture in the world consumed fermented vegetables, dairy and meat. Fermentation reaches back six thousand years into Chinese culture, the Aboriginal peoples of Australia buried sweet potatoes, and ancient Roman manuscripts describe lacto-fermented sauerkraut.

But does it still have a place in the modern world? Are there any health benefits from fermentation?

According to Jordan Rubin, author of The Maker’s Diet, “[f]ermentation is especially effective in releasing important nutritional compounds through “pre-digestion” that would otherwise pass through the human digestive system, undigested and unused.” It seems that, by expunging fermented foods from our diet, we’re not getting the most out of our foods as we should.

Luckily, however, we have kombucha, probably the easiest to consume modern fermented product—and one you can make yourself.