Small amounts of plain, low-fat, unsweetened yogurt can be an occasional treat for some cats as the cultures in the yogurt break down the lactose. But as with all dairy products, it’s a good idea to consult your vet and monitor your cat for any reactions. Small amounts of plain, low-fat, unsweetened yogurt can be an occasional treat for some cats as the cultures in the yogurt break down the lactose. But as with all dairy products, it’s a good idea to consult your vet and monitor your cat for any reactions.