Tabbed as an “it” health food of the 21st century, kefir is a probiotic drink that contains many bioactive compounds, including up to 30 different strains of “good guy” bacteria.
These probiotics, such as lactic acid bacteria, are capable of helping boost immune function and fight against harmful microbes and carcinogens — plus they are often considered key to improving many digestive issues.
Still wondering: Should I drink kefir? Below is what you need to know about this superstar beverage and why you should consider adding it to your next shopping list.
What Is Kefir?
Kefir is a fermented milk drink made using starter “grains,” which are actually a combination of bacteria and yeast. Kefir grains interact with milk to make a lightly fermented drink that even people with lactose intolerance can usually drink.
This drink can be made using just about any type of milk, such as goat, sheep, cow, soy, rice or coconut milk. It can even be made using coconut water.
Scientifically speaking, milk kefir grains contain a complex microbial symbiotic mixture of lactic acid bacteria and yeasts in a polysaccharide–protein matrix.
This probiotic drink has been used for thousands of years in many different cultures around the globe, especially those residing in Eastern Europe. Derived from the Turkish word keyif, or “feeling good,” it comes from the Eastern European Caucasus Mountains.
It’s thought that it was first discovered by sheep herders who accidentally fermented milk in their leather flasks. The potency and powerful effects of the mixture soon spread around the tribes and was later picked up by Russian doctors, who heard of its legendary healing benefits and used it to help treat ailments like tuberculosis in the 19th century.
Today, kefir has become a worldwide phenomenon. Sales in the U.S. alone by Lifeway, which accounts for 97 percent all kefir sales in the U.S., reported a growth from $58 million in 2009 to over $130 million in 2014.
However, although this popular probiotic drink is widely available and there are many options for where to buy kefir, it can also be made right from your own kitchen. In fact, there are plenty of recipes out there for how to make kefir grains and interesting ways that you can use them in soups, stews, smoothies, baked goods and more.
Why is kefir really good for you? Like other milk products, it’s a good source of calcium, plus it contains high levels of vitamin B12, magnesium, vitamin K2, biotin, folate, enzymes and probiotics.
It does not have a standardized nutrition content, however, because the values can vary based on the cows, cultures and region where it’s produced.
As an example, one cup of store-bought whole milk kefir contains the following nutrients:
- 160 calories
- 12 grams carbohydrates
- 10 grams protein
- 8 grams fat
- 390 milligrams calcium (30 percent DV)
- 5 micrograms vitamin D (25 percent DV)
- 90 micrograms vitamin A (10 percent DV)
- 376 milligrams potassium (8 percent DV)
Something unique about this beverage that is responsible for many of the health benefits of kefir is its probiotics content. According to a 2019 study, it can contain more than 50 species of probiotic bacteria and yeasts, such as the following types:
- Kluyveromyces marxianus/Candida kefyr
- Lactococcus lactis subsp. lactis
- Lactococcus lactis subsp. cremoris
- Streptococcus thermophilus
- Lactobacillus delbrueckii subsp. bulgaricus
- Lactobacillus casei
- Kazachstania unispora
- Lactobacillus acidophilus
- Bifidobacterium lactis
- Leuconostoc mesenteroides
- Saccaromyces unisporus
In a 2015 study published in Frontiers in Microbiology, kefir was recognized as a potential source of probiotics and molecules with several healthy properties. According to the authors, “its biological properties suggest its use as antioxidant, anti-tumor agent, antimicrobial agent, and immunomodulator, among other roles.”
Another 2020 article published in the journal Nutrients notes, “Kefir exhibits many health benefits owing to its antimicrobial, anticancer, gastrointestinal tract effects, gut microbiota modulation and anti-diabetic effects.”
Here’s more about some of its main benefits:
1. Contains Probiotics That Can Boost Immunity
Kefir contains many probiotics, compounds and nutrients, like biotin and folate, that help kick your immune system into gear.
One probiotic strain in particular that’s specific to kefir alone is called Lactobacillus Kefiri, which studies suggest helps defend against harmful bacteria like salmonella and E. coli. This bacterial strain, along with the various handful of others, helps modulate the immune system and inhibits the growth of harmful bacteria.
It also contains another powerful compound found only in this probiotic drink, an insoluble polysaccharide called kefiran that’s been shown to contain antimicrobial properties that can fight against candida.
Additionally, it has the ability to help lower oxidative stress, cholesterol and blood pressure levels. One study found evidence that bacterial populations found in this beverage had favorable effects on a number of metabolic syndrome parameters.
2. Builds Bone Strength
Kefir made from whole fat dairy is a good source of calcium, along with vitamin K and other minerals that support bone health. Perhaps more importantly, it holds bioactive compounds that help absorb calcium into the body and stop bone degeneration.
Vitamin K2 has been shown to be vital in improving calcium absorption as well as bone health and density. The probiotics in this beverage improve nutrient absorption, and the dairy itself contains all of the most important nutrients for improving bone strength, including phosphorus, calcium, magnesium, vitamin D and vitamin K2.
3. Potentially Helps Fight Cancer
Certain compounds found in probiotic drinks have been shown to help defend against the spread of cancer cells in the stomach in some in vitro studies.
Drinking this beverage may help slow the growth of early tumors and their enzymatic conversions from non-carcinogenic to carcinogenic. One in vitro test showed that it could reduce breast cancer cells by 56 percent, as opposed to yogurt strains, which reduced the number of cells by 14 percent.
4. Supports Digestion and Gut Health
Research indicates that consuming probiotic foods can help restore gut balance and fight against gastrointestinal diseases like irritable bowel syndrome, Crohn’s disease and ulcers.
Consuming probiotics also helps your gut after taking antibiotics. The probiotic compounds help restore the lost flora that fight against pathogens.
Probiotics can also aid against disruptive diarrhea and other gastrointestinal side effects caused by these types of medications.
Additionally, there’s evidence that because it can alter gut microbiota composition in a positive way, studies have found that drinking kefir may help improve physical performance and combat physical fatigue.
5. Improves Allergies
Various forms of allergies and asthma are all linked to inflammatory issues in the body. This drink may help treat inflammation at the source to help reduce the risk of respiratory issues like allergies and asthma.
According to an animal study in Immunobiology, it was shown to reduce inflammatory cells disrupting the lungs and air passages as well as decrease mucus buildup in mice.
The live microorganisms present in this beverage seem to help the immune system naturally suppress allergic reactions and aid in changing the body’s response to the systemic outbreak points for allergies. Some scientists even believe these allergic reactions may be the result of a lack of good bacteria in the gut.
6. Supports Skin Health
Kefir helps bring good bacteria back to the forefront and supports the health of your largest organ, the skin. Not only does it help with systemic based skin issues, but it can help recovery from skin issues like burns and rashes.
Aside from probiotics aiding the health of the immune system, the carbohydrate found in kefir known as kefiran has also been shown to improve the quality of skin wound healing and may also be protective for connective tissue.
7. Improves Lactose Intolerance Symptoms
The good bacteria found in many dairy products is essential for a healthy gut and body. However, there are many out there who cannot tolerate dairy because they are unable to digest lactose, the key sugar found in milk (thus dealing with lactose intolerance).
The active ingredient in kefir helps break lactose down and makes it easier to digest. Furthermore, this beverage has a larger range of bacterial strains and nutrients, some only specific to kefir, that help remove almost all of the lactose in the dairy.
Research published in the Journal of the Academy of Nutrition and Dietetics even unearthed that “kefir improves lactose digestion and tolerance in adults with lactose malabsorption.” As a disclaimer, although most people do very well with goat milk kefir, a small percent of people may still have issues with dairy and may need to opt for coconut or water kefir instead.
Even if you can’t tolerate any dairy, there are types of kefir that are still rich in probiotics and have plenty of healthy kefir benefits but are completely lactose- and dairy-free. There are essentially two main types, and they differ in multiple ways.
The two types of kefir are:
- Milk kefir (made from cow, sheep or goat milk but also from coconut milk)
- Water kefir (made from sugary water or coconut water, both of which do not contain any dairy)
While the base liquid used in different types varies, the process for making kefir is still the same, and the multitude of kefir benefits are thought to be present in both types.
All kefir is made using kefir grains, which are a yeast/bacterial fermentation starter. All types are similar to kombucha (another healthy probiotic-rich drink) in that they must have sugar either naturally present or else added in order to allow the healthy bacteria to grow and for the fermentation process to take place.
However, the end result is that both kombucha and kefir are very low in sugar, because the live active yeast essentially “eats” the large majority of the added sugar during the fermenting process.
Here is more information about how the different types are made and how their tastes and uses differ:
Milk kefir is the type of fermented milk drink that’s most well-known and widely available, usually sold in most major supermarkets and nearly all health food stores.
This type is most often made from goat’s milk, cow’s milk or sheep’s milk, but certain stores also carry coconut milk kefir, which means it does not contain any lactose, dairy or real “milk” at all.
Traditionally, making milk kefir has involved the use of a starter culture containing lactic acid bacteria, which is what ultimately allows the probiotics to form.
What is the difference between kefir and yogurt? Is kefir healthier than yogurt?
Typically, both are made with a starter kit of “live” active yeast, which is responsible for culturing the beneficial bacteria. Unlike yogurt, kefir comes solely from mesophilic strains, which cultures at room temperature and does not require heating at all.
They have many similarities, but kefir tends to have a higher probiotic count and more diversity of bacterial strains and yeasts.
Once fermented, milk kefir has a tart taste that’s somewhat similar to the taste of Greek yogurt. How strong the taste is depends on how long the drink has been fermented — a longer fermenting process usually leads to a stronger, tarter taste and even yields some carbonation, which results from the active yeast.
Milk kefir is not naturally sweet on its own, but other flavors can be added to it in order to boost the flavor and make it more appealing.
Most store-bought kefirs are flavored with additions like fruit or cane sugar, but you can sweeten and flavor it yourself at home by adding raw honey, maple syrup, vanilla extract or organic stevia extract.
Beyond just drinking milk kefir, there are other clever ways to use it in recipes:
- It can make a great base for soups and stews that would otherwise call for regular buttermilk, sour cream, heavy cream or yogurt.
- You can substitute plain or flavored kefir for any of these ingredients in your favorite recipes for baked goods, mashed potatoes, soups and more in order to boost the nutrient content and get all the wonderful kefir benefits.
- You can even use it to make kefir cheese, a type of hard, crumbly cheese that can be sprinkled over your favorite dinner dishes.
Coconut kefir can be made either using coconut milk or coconut water.
Both types are dairy-free and often considered the perfect base for creating fermented kefir because they naturally have carbohydrates present, including sugars, which are needed to be consumed by the yeast during the fermentation process.
Coconut kefir is made in the same way as milk kefir. It contains live active yeast and bacteria from kefir grains.
It becomes more tart and also carbonated once fermented and tends to be sweeter and less strongly flavored than milk kefir.
Both types of coconut kefir still taste like natural coconut and also keep all of the nutritional benefits of unfermented plain coconut milk and water, including providing you with potassium and electrolytes.
Water kefir tends to have a more subtle taste and a lighter texture than milk kefir, and it’s normally made using sugar water or fruit juice.
Water kefir is made in a similar way as milk and coconut kefirs. Just like the milk variety, plain water kefir can be flavored at home using your own healthy additions and makes a great, healthy alternative to drinking things like soda or processed fruit juice.
You want to use water kefir differently than you use milk kefir. Try adding it to smoothies, healthy desserts, oatmeal, salad dressing or just drink it plain.
Since it has a less creamy texture and is less tart, it’s not the best substitute for dairy products in recipes.
Related: Top 7 Sour Cream Substitute Options & How to Use Them
Risks and Side Effects
When consumed in moderation, this drink can be a safe and healthy addition to your diet.
In some cases, it may cause certain kefir side effects, including gas, bloating, nausea, diarrhea or stomach pain if consumed in high amounts. These symptoms are more common when first trying it and typically subside over time with continued use.
Many people wonder: How much kefir should I drink? Is it safe to drink kefir every day?
Most sources recommend aiming for about one cup per day to maximize the health benefits of this power-packed beverage. Ideally, start with a lower dosage and slowly work your way up to the desired amount to assess your tolerance and decrease negative side effects.
Keep in mind that milk kefir is made from dairy and is not suitable for those with a milk allergy or sensitivity to dairy products. Additionally, while most people with lactose intolerance can tolerate it without any issues, it may cause adverse side effects in others.
If you experience negative symptoms after consuming kefir milk, try swapping it for fermented drinks made with coconut or water instead.
Does kefir cause weight gain? It shouldn’t on its own, as long as you include it in an otherwise healthy diet.
In fact, it may even help support weight loss/weight maintenance due to its high nutrient content. That said, choose types that are unsweetened and low in sugar for the most benefits with fewest empty calories.
- Kefir is a fermented milk drink that is similar to yogurt but even more potent.
- Benefits of kefir include helping boost immunity, build bones strength, promote digestive health, reduce allergies, support skin health and more.
- It’s a good source of not only probiotics, which aid in gut health, but also calcium, protein, potassium, B vitamins and more.
- Best of all, it’s extremely easy to make in your own home. It can be used in smoothies or in place of milk/yogurt/cream when cooking.
- The success and power of your kefir relies on the quality of the grains, so it’s paramount to find reputable retailers selling top-rate, fresh grains in order to optimize kefir benefits.