A new Japanese study suggests that kefir, the probiotic-rich fermented milk drink, may do more than boost gut health — it could actually help slow the aging process.

Kefir is a fermented drink made with kefir grains. It’s full of natural probiotics, and is easy to digest for better digestion, immunity and healthy gut. Kefir is a simple fermented drink made by ...

You could say that kefir has it all. The fermented milk product—which is made from milk and “kefir grains” consisting of bacteria and yeast—is rich in probiotics, B vitamins, vitamin C, and calcium.