Do kefir’s pro-immunity benefits live up to the hype?
Kefir is a traditional drink that has been popular for hundreds — if not thousands — of years. It originally came out of the Caucasus Mountains in the former Soviet Union, in Central Asia. Today, we’re learning that the benefits of homemade milk kefir may be more than we ever imagined.
A tangy, refreshing glass of fermented milk kefir, made with our handy Kefir Starter, provides nourishment for the whole family. Homemade milk kefir is chock-full of beneficial bacteria and yeast that support healthy digestion and a robust inner ecology.
The word kefir is derived from the Turkish word keyif, which means “good feeling.”1
Feel-good fermented foods have been catching on. You can find kefir on most grocery store (and even convenience store) shelves. It’s been featured in Vogue, and celebrity trainers are also reportedly recommending it.
Over the years, the “good feeling” that comes with drinking kefir has been validated by science — kefir is more than a tasty beverage. It’s a traditional, living superfood that can radically contribute to overall health.
What is kefir, and why should you drink it?
Kefir is a fermented milk beverage. And:
- The lactic acid in kefir helps create its sour taste.
- While kefir is traditionally made with dairy, you can make it from raw coconut water or fresh coconut milk.
- Because homemade milk kefir is fermented, the beneficial bacteria and yeast have consumed much of the lactose (milk sugars) normally found in diary.
- Those who are lactose intolerant — or do not have the enzymes to break down milk sugars — can often safely enjoy homemade dairy kefir.
The fermentation process is also enzyme-rich. Difficult proteins like milk casein are pre-digested. If you’re sensitive to foods that contain milk casein, you may be able to drink homemade kefir after the health of your gut lining has been addressed and your inner ecosystem is restored.
Cooking for your best health can be easy. Pick from more than 250 recipes, including Young Coconut Kefir and Coconut Kefir “Cheese.”
These are the benefits of homemade milk kefir
Because homemade kefir contains beneficial bacteria and yeast, it supports digestion and the health of the digestive tract. The therapeutic effects of traditional kefir are found to include antimicrobial activity, anti-inflammatory and healing properties, a positive impact on the G.I. tract, anti-carcinogenic potential, and overall immune stimulation benefits, among others.2
Beneficial bacteria manufacture nutrients like biotin, folate, and vitamin K2.3 These are nutrients that help protect our cells from damage, nourish the brain, and support the skeletal system. Like any fermented food, kefir introduces beneficial microbes to the gut that compete for resources.
Good bacteria actively fight harmful bacteria by making their own natural antibiotics, like:
- Bacteriocins
- Lactic acid
- Short-chain fatty acids, like butyric acid (also found in butter)
The bacteria in kefir produce a structural sugar called kefiran.
Studies have found that:
- Kefiran may have the ability to help reduce cholesterol; it may also help lower blood pressure.4,5
- In a 2010 study with rabbits, researchers found that kefiran had such a profound anti-inflammatory effect that it could even help prevent atherosclerosis.6
And, research indicates that:
- Kefir may inhibit the growth of dangerous bacteria like Salmonella and Escherichia coli.7
- Kefir may help to control candida overgrowth.8
- The good bacteria found specifically in kefir may help cleanse the toxins released by harmful bacteria, like Clostridium difficile.9
- Kefir may also control the production of aflatoxin.10 Aflatoxin is a toxin produced by the Aspergillus fungus. It’s common in peanut butter.
The beneficial yeast in kefir — like Kluyveromyces marxianus and Saccaromyces — may help shut down inflammation in the intestinal tract.11
Likewise:
- The good bacteria in kefir may have the ability to help detoxify poisons known to cause cancer.12
- One study published in 2011 showed that kefir may reduce damage to the DNA in colon cells — reducing the risk of colorectal cancer.13
- Another study found that kefir may help trigger cancer cells in the stomach to self-destruct.14
More research proves that kefir could help reduce insulin resistance and inflammation in cases of metabolic syndrome and help inhibit tumor growth to serve as a potential breast cancer treatment.15,16 These studies tie in with what we believe to be the most impressive kefir benefit of all — kefir’s ability to modulate the immune system by supporting populations of good bacteria in the gut, from which all other health benefits stem.17
A healthy gut is the gateway to robust immunity.
The trouble with kefir grains (and what to watch out for)
Kefir is traditionally made with kefir grains. Kefir grains are not grains at all but pearly, gummy beads that grow over time. These gummy beads are what inoculate dairy, coconut milk, or coconut water. Kefir grains are visible colonies of symbiotic bacteria and yeast that have built a biofilm — or gummy matrix.
The problem with kefir grains is that the strains of bacteria and yeast are unregulated. Kefir made from kefir grains is partially a wild ferment. This means that the composition of bacteria and yeast can change based on environment.
Unfortunately, not all bacteria and yeast are beneficial.
Tightly regulating your exposure to the harmful yeast found in wild ferments is especially important if you struggle with:
- Candida overgrowth
- Hypothyroidism
- Immune system imbalance
- Leaky gut
- Mood and brain disorders
To mitigate the concern of wild fermentation, we’ve designed a specific blend of beneficial bacteria and yeast to use to make kefir: The Body Ecology Kefir Starter. Like dried kefir grains, spray-drying upholds the life-force of beneficial microbes. Strains of bacteria and yeast from kefir grains can be isolated and preserved through spray-drying.18
Here’s how to food combine with dairy kefir
Even though homemade kefir is fermented and pre-digested, it’s still a good idea to follow the Body Ecology Diet Food Combining Principle.
This means that you only combine dairy kefir with:
- Acidic fruits, such as lemon, lime, and berries
- Non-starchy vegetables, such as raw, leafy greens
- Seeds and nuts that are soaked and sprouted
A delicious way to enjoy homemade milk kefir is to make a salad dressing using lemon juice, avocado, Celtic sea salt, and fresh herbs. Drizzle the dressing over mixed field greens and toss. You can also sprinkle soaked and sprouted pumpkin seeds on top of your salad. They combine well with dairy kefir and raw, leafy greens.
If you’re new to using fermented dairy for fresh and flavorful home cooking, our delicious, nutritious kefir recipe guide can get you started.
REFERENCES:
- 1. Lopitz-Otsoa, F., Rementeria, A., Elguezabal, N., & Garaizar, J. (2006). Kefir: A symbiotic yeasts-bacteria community with alleged healthy capabilities. Revista Iberoamericana De Micología, 23, 67-74.
- 2. Braz J Microbiol. 2013; 44(2): 341–349.
- 3. O’Hara AM, Shanahan F. (2006) The gut flora as a forgotten organ. EMBO Rep, 7:688–93.
- 4. Bourrie BC, Willing BP, Cotter PD. The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir. Front Microbiol. 2016;7:647. Published 2016 May 4. doi:10.3389/fmicb.2016.00647.
- 5. Bellikci-Koyu E, Sarer-Yurekli BP, Akyon Y, et al. Effects of Regular Kefir Consumption on Gut Microbiota in Patients with Metabolic Syndrome: A Parallel-Group, Randomized, Controlled Study. Nutrients. 2019;11(9):2089. Published 2019 Sep 4. doi:10.3390/nu11092089.
- 6. Uchida, M., Ishii, I., Inoue, C., Akisato, Y., Watanabe, K., Hosoyama, S., … & Kitada, M. (2010). Kefiran reduces atherosclerosis in rabbits fed a high cholesterol diet. Journal of Atherosclerosis and Thrombosis, 17(9), 980.
- 7. Golowczyc, M. A., Gugliada, M. J., Hollmann, A., Delfederico, L., Garrote, G. L., Abraham, A. G., … & De Antoni, G. (2008). Characterization of homofermentative lactobacilli isolated from kefir grains: potential use as probiotic. Journal of Dairy Research, 75(02), 211-217.
- 8. Rodrigues, K. L., Caputo, L. R. G., Carvalho, J. C. T., Evangelista, J., & Schneedorf, J. M. (2005). Antimicrobial and healing activity of kefir and kefiran extract. International Journal of Antimicrobial Agents, 25(5), 404-408.
- 9. Carasi, P., Trejo, F. M., Pérez, P. F., De Antoni, G. L., & Serradell, M. L. (2012). Surface proteins from Lactobacillus kefir antagonize in vitro cytotoxic effect of Clostridium difficile toxins. Anaerobe, 18(1), 135.
- 10. Ismaiel, A. A., Ghaly, M. F., & El-Naggar, A. K. (2011). Milk kefir: ultrastructure, antimicrobial activity and efficacy on aflatoxin B1 production by Aspergillus flavus. Current Microbiology, 62(5), 1602-1609.
- 11. Romanin, D., Serradell, M., González Maciel, D., Lausada, N., Garrote, G. L., & Rumbo, M. (2010). Down-regulation of intestinal epithelial innate response by probiotic yeasts isolated from kefir. International Journal of Food Microbiology, 140(2), 102-108.
- 12. Morotomi M, Mutai M. (1986) In vitro binding of potent mutagenic pyrolysates to intestinal bacteria. J Natl Cancer Inst, 77:195–201.
- 13. Grishina, A., Kulikova, I., Alieva, L., Dodson, A., Rowland, I., & Jin, J. (2011). Antigenotoxic Effect of Kefir and Ayran Supernatants on Fecal Water-Induced DNA Damage in Human Colon Cells. Nutrition and Cancer, 63(1), 73-79.
- 14. Gao, J., Gu, F., Ruan, H., Chen, Q., He, J., & He, G. (2013). Induction of apoptosis of gastric cancer cells SGC7901 in vitro by a cell-free fraction of Tibetan kefir. International Dairy Journal.
- 15. Rosa DD, Grześkowiak ŁM, Ferreira CL, Fonseca AC, Reis SA, Dias MM, Siqueira NP, Silva LL, Neves CA, Oliveira LL, Machado AB, Peluzio MD. Kefir reduces insulin resistance and inflammatory cytokine expression in an animal model of metabolic syndrome. Food Funct. 2016 Jul 7.
- 16. Zamberi NR, Abu N, Mohamed NE, Nordin N, Keong YS, Beh BK, Zakaria ZA, Nik Abdul Rahman NM, Alitheen NB. The Antimetastatic and Antiangiogenesis Effects of Kefir Water on Murine Breast Cancer Cells. Integr Cancer Ther. 2016 May 26.
- 17. Bourrie BC, Willing BP, Cotter PD. The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir. Front Microbiol. 2016 May 4;7:647.
- 18. Golowczyc, M.A., Silva, J., Abraham, A.G., De Antoni, G.L. and Teixeira, P. (2010), Preservation of probiotic strains isolated from kefir by spray drying. Letters in Applied Microbiology, 50: 7–12.