Kefir is a healthy food, as it is a good source of probiotics, calcium, protein and B vitamins. Probiotics are naturally occurring live organisms in the human body that help prevent the growth of unhealthy bacteria in the digestive tract. Kefir contains three times more probiotics than yogurt.
Kefir also contains 20 percent of the daily recommended amount of calcium in each 175-gram serving. Calcium strengthens bones and teeth. Kefir has 10.5 grams of protein in a single serving of less than 100 calories. Kefir is also a source of several B vitamins, which strengthen the blood and nervous system and help the body withstand stress.