Benefit
Yoghurt has nutritional benefits beyond those of milk: people who are moderately lactose-intolerant can enjoy yoghurt without ill effects, because the lactose in the milk precursor is converted to lactic acid by the bacterial culture. The reduction of lactose bypasses the affected individuals' need to process the milk sugar themselves.
Yoghurt also has medical uses, in particular for a variety of gastrointestinal conditions and in preventing antibiotic-associated diarrhea. One study suggests that eating yoghurt containing L. acidophilus helps prevent vulvovaginal candidiasis, though the evidence is not conclusive.
Yoghurt is believed to promote good gum health, possibly because of the probiotic effect of lactic acids present in yoghurt.