Here's Everything You Ever Wanted to Know About Kefir

fruits & a glass of kefir

Liz deSousa for BYRDIE

In case you missed the memo, not all bacteria is bad news. Some, like the probiotics found in yogurt, can help with everything from digestion to clearing up acne. (Or, you can always apply it topically—we dug into that topic here.) Though yogurt is touted as the probiotic superhero, there’s a not-so-new kid on the block that's even more filled with probiotics, and if you don't know about it, you should. Allow us to introduce you to kefir, yogurt’s more potent, probiotic-filled, Eastern European counterpart. Curious?

benefits of kefir
Emily Roberts/Byrdie

What is Kefir?

Like yogurt, it’s full of good-for-you probiotics. But unlike yogurt, kefir isn't cultured with heat. Instead, you can turn any kind of milk (including dairy or nut milks) or water into kefir with kefir grains. But before gluten-free peeps prematurely turn away, allow us to clarify: Kefir “grains” aren’t really grains at all, but instead cottage cheese-looking little clumps made up of the bacteria and yeast that ferment the kefir. If that makes you squeamish, we get it, but it shouldn’t—you strain the final kefir, so it’s a smooth liquid consistency that’s perfect for blending with smoothies. You can also drink it straight up. Depending on what kind of liquid you used with the kefir grains, the taste can vary from slightly tart to extremely mild, with a slight yeast-y taste.

Use kefir as a substitute for sour cream or dairy when baking.


  • Great source of calcium and protein: Now, let’s talk about the benefits. First up, kefir is a great source of drinkable calcium—this is especially good news for anyone who is lactose intolerant. In a study in the Journal of the American Dietetic Association, researchers found that lactose intolerant individuals reported few or no symptoms after drinking kefir, as compared to milk. One serving of kefir will give you 20 percent of your daily calcium intake and is only 90 calories, as compared to the 150 calories in yogurt made from whole milk. Protein-wise, kefir also wins—one serving is 6 grams of protein.
  • It's a relaxant: Ever heard of tryptophan? It’s the amino acid found in some foods that has a calming effect on your nervous system; it's part of what gives you that warm, relaxed feeling. Kefir is a great source of it. If you’re stressed and battling insomnia, have a cup before bed as a nightcap and instantly feel more relaxed. (You can also try this breathing trick.) Or, have some for breakfast to start your day on a relaxed and not jittery note.
  • Aids digestion: Probiotics can help aid digestion. Researchers believe that when the microflora in your intestines aren’t balanced, certain health problems can come up (or, just bloating and indigestion). Kefir is an excellent source of probiotics, with three times the amount as yogurt. It also contains some probiotic strains that aren’t found in yogurt, due to the fact that 10 to 20 different types of probiotic bacteria and yeasts need to be mixed together in order to ferment the milk (or water) for kefir.

What Is Microflora?

A community of bacteria and other microorganisms that live inside the intestines and help to digest food.

  • Lowers blood pressure: In one study, researchers found that a probiotic found in kefir lowered blood pressure and blood glucose in mice (plus, some backed-up mice found relief after consuming it too). Promising, right?

How to Make Kefir at Home

Since kefir just involves placing the “grains” in a liquid and allowing them to ferment, this means technically you can make water kefir. It’s has a taste reminiscent of kombucha, and you can add sweetener or flavors to it, and take it on-the-go. You could also try coconut milk kefir if you’re feeling especially adventurous.

How to make kefir
The Kitchn

You can buy kefir drinks at some health food grocery stores like Whole Foods, but it’s also easy to make your own. (You can order fresh kefir grains online). After you have the grains, just put them in your milk of choice and store it in a glass jar for about 24 hours at room temperature, then strain out the liquid. Fun fact: You can actually keep the kefir (or whatever didn’t get through the strainer) and reuse it over and over again for future batches. Click here for a step-by-step guide!

Potential Side Effects

While some people experience great benefits from kefir, it's important to acknowledge that it's not right for every body. The gastrointestinal system is complicated, and it needs to have just the right balance of bacteria in order to function properly. Introducing other sources of bacteria can lead to side effects, particularly within the first few weeks. Generally, this takes the form of intestinal cramps, bloating, diarrhea, and gas—however, with continued use, those things will go away.

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Hertzler SR, Clancy SM. Kefir improves lactose digestion and tolerance in adults with lactose maldigestion. Journal of the American Dietetic Association. 2003;103(5):582-587. doi:10.1053/jada.2003.50111

  2. Jenkins T, Nguyen J, Polglaze K, Bertrand P. Influence of Tryptophan and Serotonin on Mood and Cognition with a Possible Role of the Gut-Brain AxisNutrients. 2016;8(1):56. doi:10.3390/nu8010056

  3. Valdes AM, Walter J, Segal E, Spector TD. Role of the gut microbiota in nutrition and health. Bmj. 2018. doi:10.1136/bmj.k2179

  4. Maeda H, Zhu X, Omura K, Suzuki S, Kitamura S. Effects of an exopolysaccharide (kefiran) on lipids, blood pressure, blood glucose, and constipation. BioFactors. 2004;22(1-4):197-200. doi:10.1002/biof.5520220141

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