Kefir: 7 Health Benefits & How to Make (Milk & Water Kefir)

Updated in September 2023

Kefir is a fermented milk that is rich in bacteria and probiotic yeasts. It can promote intestinal health, facilitate digestion and increase immunity, contributing to your body's general health. Kefir is also rich in protein, calcium, vitamin D and vitamin K2, which are nutrients that are essential for maintaining healthy bones and preventing the development of osteoporosis.

The bacteria in kefir can be safely cultivated at home. Making this drink is easy and is similar to the production of natural yogurt, It can be made with any type of milk or water, including coconut water.

Kefir can be consumed for breakfast or as a snack, and can be flavored with honey or fruit. 

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Kefir de leite

Health benefits

The main benefits of kefir are:

1. Boost immunity

Kefir increases immune system activity, as it contains nutrients like biotin and folate that help to protect the body's cells. Furthermore, kefir is rich in probiotics, which are bacteria that help to fight and inhibit the growth of bacteria that cause damage to the body, such as Salmonella sp. and Escherichia coli. Read more about the benefits of probiotics and why they are important to our health.

Furthermore, kefir is rich in kefiran, a polysaccharide with antimicrobial properties that help fight Candida albicans fungus.

2. Improve intestinal health

The beneficial bacteria present in kefir act to balance the intestinal flora and promote the proper functioning of the intestine. It can be used to complement the treatment of some gastrointestinal diseases, such as irritable bowel syndrome, Crohn's disease and ulcers.

Consuming kefir also helps control diarrhea and regulate bowel movements during and after taking antibiotics by restoring natural flora in the gut.

3. Improve lactose intolerance

Kefir contains active ingredients that help separate lactose from milk. This can facilitate digestion and is, therefore, beneficial for people who are lactose intolerant, as they do not have the digestive enzymes necessary to breakdown this sugar.

4. Prevent osteoporosis

Kefir is rich in calcium and also contains bioactive compounds that promote the absorption of this mineral into the body. It can help to maintain bone health and prevent bone degeneration, as well as the development of osteoporosis.

The probiotics present in kefir improve overall nutrient absorption. It also contains other important nutrients for promoting bone strength, like phosphorus, calcium, magnesium, vitamin D and vitamin K2.

5. Fight cancer

The probiotic compounds in kefir help to prevent the spread of cancer cells. It can slow down tumor growth and even prevent different types of cancer, such as stomach and breast cancer.

6. Reduce allergies

The live microorganisms present in kefir help the immune system to naturally suppress allergic reactions. They can change how intensley the body responds to allergy triggers and can reduce related inflammation that can be associated with health conditions like asthma.

7. Maintain healthy skin

Kefir helps to maintain balance in the intestinal flora, promoting the growth of beneficial bacteria in the body. This can help to keep the skin healthy and prevent the appearance of acne, psoriasis or eczema, for example.

Furthermore, the carbohydrates present in kefir, also known as kefiran, boost wound healing and also help to protect connective tissue.

Kefir for weight loss

Kefir is a low-calorie food, as 100 g contains only 37 calories. This makes it a good option to incorporate into weight loss diets.

You can consume kefir once a day, for breakfast or as a snack, for example. To enhance its flavor, you can sweeten it with a little honey, or by adding fruit such as banana or strawberries to make a smoothie.

Kefir helps to manage constipation, and more frequent bowel movements may lead to reduced bloating within a week. While this can improve the appearance of a rounded belly, you should incorporate kefir into a weight loss diet and an active lifestyle to see long-lasting weight loss. 

Where to buy

It is possible to buy kefir grains online, while kefir milk can be found in supermarkets or health food stores. Exchanges between friends or on online forums are very common because the grains are grown in a liquid environment and multiplied. A portion of this kefir must be removed to prevent excessive growth, which is why those who have it at home usually offer it to family and friends.

Kefir grains are also called Tibetan Mushrooms, Yogurt Plants, Yogurt Mushrooms, Yogurt Fungus and Snow Lotus. They originated in the Caucasus area and are made up of different microorganisms.

How to make milk kefir

Making kefir is very simple and similar to making natural yogurt at home. You can use any type of milk: cow, goat, sheep, coconut, rice or almond milk.


  • 100 g of milk kefir
  • 1 liter of milk

How to prepare

Place the kefir grains and fresh milk (whether pasteurized or not, skimmed, semi-skimmed or whole) in a glass container. The contents are left at room temperature for approximately 24 hours. The fermented milk is strained and stored, while the strained grains are added to more fresh milk, repeating the process.

Already fermented liquid kefir that is strained can be consumed immediately or can be kept in the refrigerator for later consumption.

How to make water kefir

Water kefir is made using coconut water or mineral water and adding brown sugar.


  • 3-4 tablespoons of water kefir grains
  • 1 liter of water
  • 1/4 cup of brown sugar

How to prepare

In a glass jar, add water and brown sugar and dilute well. Add the kefir grains and cover the top of the jar with a paper towel, gauze or thin cloth, securing it with an elastic band to keep it secure. Leave in a dark place, at room temperature, to ferment for 24 to 72 hours. The longer it ferments, the less sweet the final drink will be. After fermentation, strain the grains to use them for the next fermentation.

Flavoring water kefir

After fermentation, water kefir can be mixed with fruit juices, teas, ginger, and dried or fresh fruits to taste. Fermentation causes the drink to become slightly carbonated, making it possible to taste it to create a homemade soft drink.

Water kefir lasts from 3 days to 1 week in the refrigerator, and can be consumed as a snack or taken with  lunch or dinner. 

How to cultivate kefir

To keep kefir fresh and active, you should always store it in a container with milk or sugar water after each fermentation. Be sure not to use metal utensils when handling it and to always cover the container with gauze or a clean cloth or paper towel, so that it does not come into contact with flies or bugs. On warmer days or to delay the fermentation process, you can store the kefir in the refrigerator, but if you wish to go more days without using the kefir for fermentation, the grains should be stored in a container with a lid and frozen.

Little by little, the kefir grows with fermentation and creates a thick goo or liquid. Therefore it is necessary to rinse the grains in water at least once a week. It is possible to store part of the grains in the freezer to always have a reserve, and the remaining surplus can be donated to other people to produce their kefir at home. Be sure to remember that milk kefir grains must be kept separate from water kefir grains.

You should not use kefir grains that are green, yellow or brown, as this indicates that they are no longer suitable for consumption.

Can you use milk kefir to make water kefir?

Yes, however the process is not that simple and may not be as successful. Therefore, using of the milk kefir grains it is not recommended, and you should opt for using just a part of it.

To carry out this process, be sure that the milk kefir is active. It is also important to rehydrate it before converting it water kefir. Then, follow the following steps:

  • Dissolve ¼ cup of brown sugar in 1 liter of water and add ⅛ teaspoon of sea salt
  • Add the activated milk kefir grains to the sugar water solution and let it ferment for 5 days at room temperature
  • Strain the kefir grains, prepare another water and sugar solution, and place the grains in the new solution. Allow it to ferment at room temperature for 12 to 24 hours less than the previous time
  • You must repeat the previous step and reduce the preparation time by 12 to 24 hours each time, until the cultivation period is 48 hours or less.

At this point, the grains should be converted to water kefir, and should continue to be cultivated for another 24 to 48 hours.


Kefir is contraindicated for patients with gastrointestinal cancer. It should not be consumed 2 hours before or after taking medicines with bisphosphonate, fluorides or tetracyclines, as it can interfere with the absorption of these medications. Kefir fermentation leads to a small production of alcohol in the body, and therefore can be harmful for people with liver diseases.

Possible side effects

Excessive kefir intake can also cause problems such as abdominal pain and diarrhea, which is why more than 1 glass of kefir per day is not recommended.