What Is Kefir?

There's a lot of excitement around fermented foods and drinks, giving people hope for good gut health. People clamor for probiotic foods and drinks like miso, kimchi, and kombucha, but there's another one that gets a lot of attention: kefir. If you're confused about kefir and the two different types, we can clear up a few things.

Breaking Kefir Down

Kefir is a fermented beverage hyped for the probiotics it contains and its effect on gut health. While you may be familiar with the yogurt-like drink, there are two types of kefir: milk and water. Both are made using kefir grains—live cultures—but they are not the same grains (we'll address that below). Both types are widely available—most grocery and convenience stores carry various brands.

Milk Kefir

Milk kefir is a fermented milk drink that contains good bacteria and yeasts—probiotics—that may help maintain a healthy digestive system. Probiotics can be good for the immune system and overall health, but the effect of the milk version on your diet really depends on your diet as a whole. As for taste and texture, it's kind of like a drinkable yogurt.

The big difference is that milk kefir generally contains more strains of probiotics than regular yogurt. It typically contains five or more probiotics, while most yogurts generally contain two, such as Lactobacillus bulgaricus and Streptococcus thermophilus, but more can be added.

But that doesn't mean kefir is better than yogurt—the number of strains isn't as important as the colony-forming units (CFUs). CFUs are the number of microorganisms in a particular probiotic. That means that even if there are only two probiotics in yogurt, it may contain more CFUs than kefir with six probiotics. Some of those probiotics don't make it to your gut—stomach acid can kill them—but a standard serving of each provides plenty of good gut bacteria for the average person even if some are killed in the process.

Making the Milk Version

Milk kefir can be made at home using milk kefir grains, which are living cultures—you can buy the grains online or at specialty shops. The grains are mixed with milk and then left to ferment for 24 hours. The grains are then strained out and it's ready to drink by itself or it can be added to smoothies and other recipes.

Water Kefir

The water version is a different beverage experience than milk kefir. It's dairy-free and can be fizzy like a soda. Some people say it's similar to kombucha, only it has a more "filtered" taste. Like milk kefir, it also contains five or more probiotics, but they are a little bit different from those found in milk kefir.

The method for making water kefir is very similar to making milk kefir, but there's one major difference—the grains. Milk kefir grains are white and look like cottage cheese or cauliflower and feed on the lactose in milk during fermentation. Water kefir grains look kind of like crushed ice and feed on regular sugar during fermentation.

Making the Water Version

To make the water version, sugar is dissolved in water before the grains are added—you can also buy the grains online or at specialty shops. The solution then sits and ferments for 24 to 48 hours. The grains are then strained out and it's ready to drink. If you want it to be fizzy, you can do a second fermentation with fruit to flavor it.

Nutrition Facts

The nutritional value of commercially produced kefir milk and water may differ from what you make yourself.

Homemade Milk Kefir

Though it's considered a dairy product, the other great thing about milk kefir—as with regular and Greek yogurt—is that people who are lactose-intolerant can enjoy it too. Because the grains feed on the lactose—or milk sugar—during the fermentation process and turn it into lactic acid, there's usually not enough lactose left over to have an effect.

In addition to probiotics, milk kefir is also high in protein and high in potassium, which helps to lower blood pressure and magnesium for nerve and muscle function. It also contains a good amount of calcium to support bone health.

Per Serving Size: 3/4 cup

149 calories; 7.9 g total fat; 4.6 g saturated fat; 24 mg cholesterol; 105 mg sodium. 322 mg potassium; 11.7 g carbohydrates; 12 g sugar; 7.7 g protein; 395 IU vitamin A; 12 mcg folate; 276 mg calcium; 24 mg magnesium

Homemade Water Kefir Nutrition Facts and Health Benefits

In addition to probiotics, if you're looking for a fizzy drink, water kefir is low in calories. It doesn't contain any lactose, good to know if you are lactose-intolerant or are sensitive to lactose.

Per Serving Size: 1 cup

61 calories; 8 mg sodium. 39 mg potassium; 15.9 g carbohydrates; 0.6 g fiber; 15 g sugar; 0.2 g protein; 2 mg vitamin C; 16 mg calcium; 6 mg magnesium; 13 g added sugar