8 Evidence-Based Health Benefits of Kefir

By Joe Leech, www.authoritynutrition.com
April 30, 2015 Updated: May 8, 2015

Kefir is all the rage in the natural health community. It is high in nutrients and probiotics and is incredibly beneficial for digestion and gut health. Many people consider it to be a healthier and more powerful version of yogurt.

Here are nine health benefits of kefir that are supported by research.

1. Fantastic Source of Many Nutrients

Kefir is a fermented drink, traditionally made using cow or goat milk. It is made by adding kefir “grains” to milk. These are not grains in the conventional sense but cultures of yeast and lactic acid bacteria that resemble a cauliflower in appearance.

Over a period of 24 hours or so, the microorganisms in the kefir grains multiply and ferment the sugars in the milk, turning it into kefir. Then the grains are removed from the liquid and can be used again.

This is what kefir grains (on the spoon) look like. (Shutterstock)
This is what kefir grains (on the spoon) look like. (Shutterstock)


So basically, kefir is the drink, but kefir grains are the “starter kit” that you use to produce the drink.

Kefir originated from parts of Eastern Europe and Southwest Asia. The name is derived from the Turkish word “keyif,” which means “feeling good” after eating.

The lactic acid bacteria turn the lactose in the milk into lactic acid, so kefir tastes sour like yogurt, but has a thinner consistency.

A 6-ounce serving of milk kefir contains the following:

  • Protein: 6 grams.
  • Calcium: 20 percent of the recommended daily allowance (RDA).
  • Phosphorus: 20 percent of the RDA.
  • Vitamin B12: 14 percent of the RDA.
  • Riboflavin (B2): 19 percent of the RDA.
  • Magnesium: 5 percent of the RDA.
  • A decent amount of vitamin D.

This comes with about 100 calories, 7–8 grams of carbs, and 3–6 grams of fat, depending on the type of milk that is used. Kefir also contains a wide variety of bioactive compounds, including organic acids and peptides that contribute to its health benefits.

Dairy-free versions of kefir can be made with coconut water, coconut milk, or other sweet liquids. These will not have the same nutrient profile as dairy-based kefir.

Bottom Line: Kefir is a fermented milk drink, cultured from kefir grains. It is a rich source of calcium, protein, and B-vitamins.

2. A More Powerful Probiotic Than Yogurt

Some microorganisms can have beneficial effects on health when ingested. Known as probiotics, these microorganisms can influence health in numerous ways, including digestion, weight management, and mental health.

Yogurt is the best known probiotic food in the Western diet, but kefir is actually a much more potent source. Kefir grains contain about 30 strains of bacteria and yeasts, making it a very rich and diverse probiotic source. Other fermented dairy products are made from far fewer strains and don’t contain any yeasts.

Bottom Line: Kefir contains about 30 different microorganisms, making it a much more potent source of probiotics than other fermented dairy products.

3. Potent Antibacterial Properties

Certain probiotics in kefir are believed to protect against infections. This includes the probiotic Lactobacillus kefiri, which is unique to kefir.

Studies show that this probiotic can inhibit the growth of various harmful bacteria, including Salmonella, Helicobacter Pylori, and E. coli.

Kefiran, a type of carbohydrate present in kefir, also has antibacterial properties.

Bottom Line: Kefir contains the probiotic Lactobacillus kefiri, and the carbohydrate kefiran, both of which can protect against harmful bacteria.

4. Improve Bone Health and Lower Risk of Osteoporosis

Osteoporosis (“porous” bones) is characterized by deterioration of bone tissue and is a massive problem in Western countries. It is especially common among elderly women and dramatically raises the risk of fractures.


Ensuring an adequate calcium intake is one of the most effective ways to improve bone health and slow the progression of osteoporosis.

Kefir made from full-fat dairy is not only a great source of calcium, but also vitamin K2. This nutrient plays a central role in calcium metabolism, and supplementing with it has been shown to reduce the risk of fractures by as much as 81 percent.

Recent animal studies have shown that kefir can increase calcium absorption by bone cells. This leads to improved bone density, which should help prevent fractures.

Bottom Line: Kefir made from dairy is an excellent source of calcium. In the case of full-fat dairy, it also contains vitamin K2. These nutrients have major benefits for bone health.

5. May Be Protective Against Cancer

Cancer is one of the world’s leading causes of death. It occurs when there is an uncontrolled growth of abnormal cells, such as a tumor.

The probiotics in fermented dairy products are believed to inhibit tumor growth by reducing formation of carcinogenic compounds, as well as by stimulating the immune system. This protective role has been demonstrated in several test-tube studies.

One study found that kefir extract reduced the number of human breast cancer cells by 56 percent, compared with only 14 percent for yogurt extract. However, take all of this with a grain of salt, as this is far from being proven in living, breathing humans.

Bottom Line: Some test-tube and animal studies have shown that kefir can inhibit the growth of cancer cells. This has not been studied in people.

6. May Help With Digestive Problems

Probiotics such as kefir can help restore the balance of friendly bacteria in the gut. This is why they are highly effective for many forms of diarrhea.

There is also a lot of evidence that probiotics and probiotic foods can help with all sorts of digestive problems. This includes irritable bowel syndrome (IBS), ulcers caused by H. pylori infection, and various others. For this reason, kefir may be useful if you have problems with digestion.

Bottom Line: Probiotics like kefir can treat several forms of diarrhea. They can also lead to major improvements in various digestive diseases.

7. Generally Well-Tolerated by the Lactose-Intolerant


Regular dairy foods contain a natural sugar called lactose. Many people, especially adults, are unable to break down and digest lactose properly. This condition is called lactose intolerance.

The lactic acid bacteria in fermented dairy foods (like kefir and yogurt) turn the lactose into lactic acid, so these foods are much lower in lactose than milk. They also contain enzymes that can help break down the lactose even further.

Because of this, kefir is generally well-tolerated by people with lactose intolerance, at least as compared to regular milk.

Also keep in mind that it is possible to make kefir that is 100 percent lactose-free by using coconut water, fruit juice, or some other non-dairy fluid.

Bottom Line: The lactic acid bacteria have already pre-digested the lactose in kefir. People with lactose intolerance can often eat kefir without problems.

8. May Improve Allergy and Asthma Symptoms 



Allergic reactions are caused by inflammatory responses against harmless environmental substances. People with an over-sensitive immune system are more prone to allergies, which can provoke conditions like asthma.

In animal studies, kefir has been shown to suppress inflammatory responses related to allergy and asthma. Human studies are need to better explore these effects.

And It’s Easy to Make at Home

The last one is not a health benefit, but important nonetheless. If you are unsure about the quality of store-bought kefir, then you can easily make it at home yourself.

You can buy kefir grains in some health food stores and supermarkets. It is also available on Amazon, with hundreds of reviews, testimonials, and tips from real customers.

There are some good blog posts and videos on how to make kefir, but the process is very simple:

  • Put 1–2 tablespoons of kefir grains into a small jar. The more you use, the faster it will culture.
  • Add around 2 cups of milk, preferably organic or raw. Milk from grass-fed cows is healthiest. Leave 1 inch of room at the top of the jar.
  • You can add some full-fat cream if you want the kefir to be thicker.
  • Put the lid on and leave it for 12–36 hours at room temperature. That’s it.

Once it starts to look clumpy, it is ready. Then you gently strain out the liquid, which leaves behind the original kefir grains. Now put the grains in a new jar with some milk, and the process starts all over again.

Combined with some fresh fruit, kefir makes one of the healthiest and tastiest desserts I have ever come across—delicious, nutritious, and highly sustainable.

Joe Leech has a master’s degree in nutrition and dietetics. This article was originally published on AuthorityNutrition.com

*Image of “kefir” via Shtterstock

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