Because kefir isn't strained, it is also higher in protein. A cup of plain kefir made with whole milk has about 9 grams of protein, compared to less than 8 grams found in a cup of plain yogurt made ...

Yogurt and kefir come in dairy and non-dairy as well as plain and flavored options. There is also Greek yogurt—yogurt that's been strained to make a thicker, creamier, and higher-protein yogurt.

If replacing the kefir with plain yoghurt, you may need to thin it out with a bit of water. Basic plain yoghurt is better than thicker Greek-style yoghurt or strained yoghurt.

You can buy kefir plain or in a wide variety of flavors, like vanilla, blueberry, and strawberry at most supermarkets or health food stores like Whole Foods, Costco, Trader Joe's, and Publix.