Yogurt is a good source of several micronutrients and has played an important role in human nutrition. Consumption of yogurt has been shown to promote health benefits due to the presence of live bacteria. A number of human studies have demonstrated that yogurt contains viable bacteria, and especially L. bulgaricus, improve the health of the host and thus qualifies as a bona fide probiotic in its own right. In this chapter, we review the literature covering attributes of the yogurt bacterium L. bulgaricus that confirm its probiotic bacterial characteristics.