BENEFITS OF KEFIR
✓ Enriches the gut microbiota
✓ Reduces cholesterol levels
✓ Strengthens the immune system
✓ Relieves skin problems
✓ Potentially anti-cancer
What is kefir?
Kefir is a beverage originating from the Caucasus, a region to the east of Europe shared between Russia, Georgia, Armenia and Azerbaijan. Known worldwide for its mountain ranges and steppe landscapes, the Caucasus is home to many nomadic shepherds. They are the ones who traditionally prepare this beverage and made it popular. Its consumption later spread to other parts of the world from the end of the 19th century.
There are two types of kefir : milk kefir and water kefir (or fruit kefir).
- Le kéfir de lait est une boisson produite à partir de lait animal associé à des ferments et des levures. On obtient alors des « grains de kéfir » blancs, semblables à des petites têtes de chou-fleur. Ces derniers sont laissés en fermentation pendant 24 à 48h jusqu’à obtenir une boisson lactée.
- Le kéfir de fruits, quant à lui, est obtenu à partir de la fermentation de fruits, d’eau, de sucre et de grains de kéfir d’eau. Ces derniers sont transparents et ont l’apparence de cristaux.
Whether it’s milk or water kefir, the resulting drink is slightly fizzy, refreshing and packed with beneficial microorganisms (lactic bacteria and yeasts), as shown by this review.
This beverage also contains a wide range of nutrients : vitamins, minerals, proteins, polysaccharides…
This unique composition gives it properties and health benefits. This beverage is now recognized for nourishing the gut microbiota, lowering cholesterol levels, strengthening the immune system, and relieving skin problems. Some studies have also shown anticancer effects.
Nutritional composition
- Acides aminés
- Vitamines : A, B (B2, B5, B6, B9, B12), D, K2
- Minéraux et oligo-éléments : calcium, potassium, magnésium, phosphore, sodium…
- Protéines
- Probiotiques : bactéries et levures
- Polysaccharides : kéfiran
- Glucides
Benefits of kefir
♻️ Enriches the gut microbiota
Thanks to its composition rich in bacteria and yeasts, kefir nourishes and enriches the gut microbiota. It is a beverage that supports the existing microbial flora while boosting its activity. Thus, it is among the best natural probiotics.
Milk and fruit kefirs mainly contain lactobacilli, lactococci, and leuconostocs. These lactic bacteria are living microorganisms that ensure the proper functioning of the digestive system. The beverage notably increases the amount of actinobacteria, one of the four major families of microbiota bacteria. They themselves are composed of bifidobacteria that produce lactic acid, contribute to digestion, and fight harmful bacteria and pathogenic germs.
This study from Hacettepe University (Turkey), conducted on humans, shows how kefir consumption improves the composition of the gut microbiota.
🍳 Reduces cholesterol levels
Kefir helps reduce levels of bad cholesterol in the blood and lower blood pressure. The lactobacilli it contains promote the breakdown of cholesterol in the intestine, reducing its absorption and its production by the liver. The bacterium Lactobacillus plantarum is one of the most active: it significantly lowers total cholesterol and hepatic triglycerides.
Additionally, this beverage contains vitamin D and vitamin B5 (pantothenic acid), which can help regulate blood cholesterol and triglyceride levels. Finally, with 127 mg per 100 g, it is an excellent source of calcium, a deficiency of which is closely linked to the onset of hypercholesterolemia.
This study from Tianjin University of Science and Technology (China), conducted on mice, shows the cholesterol-lowering effect of kefir lactobacilli.
This other study from Jilin University (China), carried out on rats, shows how the bacterium Lactobacillus plantarum from kefir lowers cholesterol and triglyceride levels in the liver.
🛡 Strengthens the immune system
Another interesting effect of kefir: it strengthens the immune system and improves antibody secretion by lymphocytes. It is an immunomodulator capable of regulating the immune response.
It notably increases the level of interleukin-5 (IL-5), a glycoprotein that plays a role in the stimulation of B lymphocytes, the body’s natural defenses. It also improves the production of immunoglobulin A in the small intestine and the large intestine. The latter supports the immunity of the gastrointestinal mucosa.
By making the body’s immune response more effective, the drink helps fight certain pathogenic bacteria. Thus, it protects against Bacillus cereus, which causes food poisoning, the bacteria Salmonella, Helicobacter pylori and E. coli.
This study from the University of Moncton (Canada), conducted on mice, shows the positive impact of kefir on intestinal mucosal immunity.
This other study from Ankara Training and Research Hospital (Turkey), conducted on healthy volunteers, shows increased levels of interleukin-5 and immunoglobulin A through the microorganisms in kefir.
Finally, this other study from Uludag University (Turkey), conducted on patients infected with Helicobacter pylori, demonstrates kefir’s effectiveness in eradicating the bacterium.
🍑 Relieves skin problems
Thanks to its bacterium Lactobacillus kefiri, kefir is a valuable ally for relieving skin problems such as inflammatory acne, psoriasis, and allergic eczema.
On the one hand, it notably inhibits the production of immunoglobulin E (IgE) associated with certain skin diseases such as atopic dermatitis and psoriasis.
On the other hand, it exerts an anti-inflammatory effect that reduces the severity and symptoms of dermatological conditions.
Finally, it has a beneficial effect on the wound healing process. Kefir grains contain a polysaccharide called “kefiran”. This compound has antimicrobial and healing properties and protects the skin’s connective tissue.
This study from Unifenas University (Brazil), conducted on rats, shows the effectiveness of a kefir-based gel in wound healing.
This other study from the same university, conducted on rats, demonstrates kefir’s anti-inflammatory and wound-healing activities.
🔬 Potentially anti-cancer
More recently, some researchers have highlighted kefir’s potential for the prevention and treatment of colon, skin, breast, and stomach cancers.
On the one hand, it would slow the development and proliferation of cancer cells. On the other hand, it would also induce apoptosis (programmed cell death). Its anti-cancer action appears to be linked to the peptides, polysaccharides, and sphingolipids (complex lipids) it contains.
This review from Isfahan University of Medical Sciences (Iran) focuses on the effects of this beverage in the prevention and treatment of cancer.
This study from the American University of Beirut (Lebanon), conducted on cancer cells, shows the effectiveness of kefir in inhibiting proliferation and inducing apoptosis of malignant T lymphocytes.
How to consume kefir?
Milk kefir
Milk kefir is made from sheep’s, goat’s, or cow’s milk. The longer the fermentation, the thicker its texture and the more sour its flavor. It has a taste similar to yogurt, both tangy and creamy.
Additionally, the bacteria it contains convert lactose into lactic acid. Ultimately, milk kefir is therefore fairly low in lactose and generally well tolerated by sensitive individuals.
You can consume it plain or flavor it with vanilla, sugar, lucuma powder, honey… The milk beverage also blends easily into smoothies and can be used to replace buttermilk in baking.
Finally, you can also add 1 teaspoon of milk kefir to your cosmetics (cleanser, facial care, mask…) to rebalance the skin flora.
Fruit kefir
To prepare fruit kefir, people generally use lemon, fig, orange, or apricot that are left to ferment in sweetened water with water kefir grains.
The fruit drink has a slightly tangy and more subtle flavor than the milk one. It is also more refreshing. It is often compared to the Kombucha, a traditional Russian beverage produced by culturing yeasts and bacteria in a sweetened tea infusion.
As with milk kefir, you can flavor it with herbs and spices (ginger, mint, lemon verbena…) or freshly squeezed lemon.
Coconut water kefir
Coconut water is ideal as a base for fermenting water kefir grains because it naturally contains sugars. Simply mix the two ingredients in a jar and let them ferment for 48 hours at room temperature.
This coconut water drink has the advantage of being vegan. You can enjoy it with dried fruits or berries: goji berries, açaí berries…
Kefir powder
To prepare your own kefir, some brands offer ready-made powder that includes sugar and freeze-dried cultures. All you have to do is mix the powder into water, add the fruit (for fruit kefir), and let it ferment for 48 hours. Convenient and quick for making a delicious drink!
Dehydrated kefir grains
It is possible to find dehydrated kefir grains to make your milk- or fruit-based beverage. To rehydrate them, you should soak them in a glass of fresh milk or water. Rehydration can take several days.
Kefir and medicinal plants
To improve intestinal transit and nourish the gut microbiota, it can be combined with other natural probiotics such as miso and spirulina.
Moreover, it is also a weight-loss ally that, when combined with fat-burning foods, can help you lose weight.
To reduce levels of bad cholesterol, enjoy it with Brazil nuts, basil seeds, or hemp.
Consume sustainably: favor organic, local, and fair-trade kefir
✓ France has many producers of natural, artisanal kefir, made with organic ingredients that are local, without additives or flavorings.
✓ If you want to make your own drink, preferably choose grains from a culture based on organic products (milk, sugar, organic fruits…).
✓ If the kefir doesn’t come from France, check its exact origin and prioritize fair trade supply chains to support local producers.
Dosage
It is recommended to drink between 200 and 300 ml of kefir per day (about 1 cup). Start gradually (100 ml per day) and then increase your daily consumption according to how your body reacts.
To get results, drink kefir every day for at least 3 months.
Contraindications and side effects
Consuming kefir is not dangerous but there are some contraindications :
- Par mesure de précaution, on le déconseille aux femmes enceintes et allaitantes et aux jeunes enfants
- Les personnes souffrant de maladies auto-immunes, du syndrome de l’intestin irritable ou de la maladie de Crohn doivent éviter d’en consommer
- Les personnes sensibles aux caséines et aux levures doivent le consommer avec précaution.
Excessive consumption can cause the following adverse effects :
- Constipation
- Crampes abdominales
- Ballonnements
- Diarrhée
If you experience side effects, stop consuming it and consult a doctor.
History, cultivation, and market of kefir
In Turkish, ‘kefir’ means ‘to feel good’. A promising name! It is a drink consumed for centuries by the nomadic peoples of the Caucasus. It is said to have been born by accident. The nomads, who used to store milk in leather gourds, would have let it ferment. Finally, some attribute its origin to Japan and Tibet.
In Europe, kefir was introduced around 1860. Its quality depends on many factors: origin, composition and quality of the milk and grains, production conditions, technology used… Thus, certain fermentation conditions (duration and temperature) can optimize the anticancer properties of this beverage as shown by this review.
Report prepared by Julia Perez and Charlotte Jean
Sources and scientific studies
Analy Machado de Oliveira Leite, Marco Antonio Lemos Miguel, Raquel Silva Peixoto, Alexandre Soares Rosado, Joab Trajano Silva, Vania Margaret Flosi Paschoalin, 2013. Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage.
Maria R. Prado, Lina Marcela Blandón, Luciana P. S. Vandenberghe, Cristine Rodrigues, Guillermo R. Castro, Vanete Thomaz-Soccol, and Carlos R. Soccol, 2015. Milk kefir: composition, microbial cultures, biological activities, and related products.
Ezgi Bellikci-Koyu, Banu Pınar Sarer-Yurekli, Yakut Akyon, Fadime Aydin-Kose, Cem Karagozlu, Ahmet Gokhan Ozgen, Annika Brinkmann, Andreas Nitsche, Koray Ergunay, Engin Yilmaz, Zehra Buyuktuncer, 2019. Effects of Regular Kefir Consumption on Gut Microbiota in Patients with Metabolic Syndrome: A Parallel-Group, Randomized, Controlled Study.
Yanping Wang, Nv Xu, Aodeng Xi, Zaheer Ahmed, Bin Zhang, Xiaojia Bai, 2009. Effects of Lactobacillus plantarum MA2 isolated from Tibet kefir on lipid metabolism and intestinal microflora of rats fed on high-cholesterol diet.
Ying Huang, Xiaojun Wang, Jinfeng Wang, Fei Wu, Yujie Sui, Longfei Yang, Zonggui Wang, 2013. Lactobacillus plantarum strains as potential probiotic cultures with cholesterol-lowering activity.
Gabriel Vinderola, Gabriela Perdigón, Jairo Duarte, Edward Farnworth, Chantal Matar, 2006. Effects of the oral administration of the products derived from milk fermentation by kefir microflora on immune stimulation.
Ali Kudret Adiloğlu, Nurettin Gönülateş, Mehmet Işler, Altuğ Senol 2013. The effect of kefir consumption on human immune system: a cytokine study.
Sandra Rizk, Katia Maalouf, Elias Baydoun, 2009. The antiproliferative effect of kefir cell-free fraction on HuT-102 malignant T lymphocytes.
Kamila Leite Rodrigues, Lucélia Rita Gaudino Caputo, Jose Carlos Tavares Carvalho, João Evangelista, Jose Maurício Schneedorf, 2004. Antimicrobial and healing activity of kefir and kefiran extract.
M E C Moreira, M H Dos Santos, G P P Zolini, A T B Wouters, J C T Carvalho, J M Schneedorf, 2008. Anti-inflammatory and wound-healing (cicatrizing) activities of a carbohydrate fraction isolated from sugary kefir.
Nahid Rafie, Sahar Golpour Hamedani, Reza Ghiasvand, Maryam Miraghajani, 2015. Kefir and Cancer: A Systematic Review of Literatures.
Sandra Rizk, Katia Maalouf, Elias Baydoun, 2009. The antiproliferative effect of kefir cell-free fraction on HuT-102 malignant T lymphocytes.
Athéna Zourari, E.M. Anifantakis, 1988. Kefir. Physicochemical, microbiological and nutritional characteristics. Production technology. A review.
