saw this article that is very fitting here.
Probiotics are beneficial bacteria normally present in the digestive tract. They are vital for proper digestion, strong P vitamin activity, and also perform a number of other useful functions, such as synthesizing vitamin K, help with regulating hyaluronidase, and preventing the overgrowth of yeast and bad bacteria. The beneficial bacteria most often used in supplements are acidophilus and bifidobacteria but there are many more including B.Bifidum, B.Longum, S.Thermophilus, L.Plantarum, and Lactococcus lactis. Thanks to advertisements, many more people have become aware of probiotics in yogurt, but unfortunately, consider them only useful for digestive regularity.Although some people who have a problem with dairy can eat yogurt or other cultured dairy products like buttermilk, some cheeses and kefir, many get their food-source probiotics from supplements and cultured or fermented foods which also contain various types and amounts of beneficial bacteria. These foods include sauerkraut and tempeh.
a kefir a day keeps the doctor away...