Milk and cultures are poured into a cup where they culture for eight hours.

For a fermented dairy beverage that originated in the Caucasus Mountains more than 2,000 years ago, kefir sure is having a moment. Innova Market Insights reports that the number of kefir launches grew more than threefold globally between 2011 and 2016. In the United States, beverages featuring kefir accounted for 40% of the drinking yogurt/fermented beverage introductions in 2016.