Beet kvass is a highly nutritive, fermented drink that you make by culturing beets in a slightly salty brine. Its earthy, slightly salty and subtle sour flavor can take some getting used to. And it's worth your time to give it a try because beet kvass benefits cardiovascular, cognitive and cellular health. It also helps support the digestive system, too. And it does this by combining the nutritive power of beets with the probiotic effects of fermentation.