Kefir: Benefits, Nutrition Facts, How to Make It & Recipes

Dr. Josh Axe · Free quiz

Gut Health Quiz

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Kefir is a tangy, slightly fizzy fermented milk made by culturing milk with kefir grains, small clusters of bacteria and yeasts that turn it into one of the most microbe-rich foods you can eat.123 It's a staple of my diet and one of my top two probiotic foods, and I recommend plain goat's or sheep's milk kefir, starting with a couple of tablespoons a day and working up to about a cup.314151113

A lot of the bloating, blood-sugar swings and low-grade inflammation people live with starts in the gut, with the community of microbes that lives there, and that's exactly where kefir goes to work. Its grains turn milk into a living food: by the time you drink it, the cultures have already eaten some of the lactose and brought their own lactase along, and kefir's bacteria and yeasts can settle into your gut for a while.416217 In trials in people, that has meant easier lactose digestion, lower fasting insulin and a shift toward friendlier gut bacteria, which is food as medicine in one of its simplest forms.678

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What is kefir?

Pour a glass and you'll notice that kefir is thinner than yogurt, with a tart, slightly yeasty taste and sometimes a light fizz.1819 To make it, you drop kefir grains into milk and leave the jar on the counter for about a day. The grains feed on the milk's lactose and turn it into lactic acid, a little alcohol and carbon dioxide, which is where kefir gets its tang and its fizz, and then you strain them out and drop them into fresh milk to start again.1182 Kefir can be made from many kinds of milk, and goat's and sheep's milk make wonderful kefir.1819

Milk kefir is the original, and it has two dairy-free cousins. Water kefir is made with a different set of grains in sugar water, and the two kinds of grains aren't interchangeable, while coconut kefir is made by culturing coconut milk.220

What are kefir grains?

Despite the name, kefir grains contain no grain at all. They look like small cauliflower florets, white to yellowish and jelly-like, anywhere from about an eighth of an inch to an inch and a third across, and each one is a living colony.21 A gram of grains holds about 100 million lactic acid bacteria, 1 million to 10 million yeasts and about 100,000 acetic acid bacteria, all held together in kefiran, a matrix of glucose and galactose that the grains' own Lactobacillus kefiranofaciens makes.1

A grain works a bit like a sourdough starter you can hold in your hand. Feed it fresh milk and it keeps culturing batch after batch, and over time it grows and divides into new grains.12 That's why grains get passed from friend to friend, and you can also buy them live or dehydrated.2

Where kefir comes from

Kefir was first made centuries ago in the Caucasus Mountains, and it spread through the Balkans and Eastern Europe.2181 Traditionally, people started each batch by adding kefir grains to fresh milk in a sheep or goat skin bag.18 In 1908, Élie Metchnikoff first proposed that fermented milks support health and long life through their effect on the bacteria in the gut.18 In the Soviet era, kefir was widely recommended for healthy people and given to patients with digestive and metabolic disease, high blood pressure, heart disease and allergy.21 That long history of daily use pointed the way, and the trials in people below are now showing what a glass of kefir does for digestion, blood sugar and the gut.

Kefir as we know it comes from the Caucasus, and fermented milk like it has a long place at the table of the biblical diet. In biblical times, milk was often fermented to preserve it, and milk from animals like sheep was made into yogurt or kefir, curdled into cheese or churned into butter.22 Fermented dairy, typically cultured goat milk or cultured sheep milk, is number 10 on my list of the foods the Bible talks about, and the reason it's so beneficial is that it's very high in probiotics.23 One place it shows up is the meal Abraham set before his three visitors. Genesis 18:8 says, "And he took butter, and milk, and the calf which he had dressed, and set it before them; and he stood by them under the tree, and they did eat."24

Kefir probiotics: strains and counts

The bacteria in kefir are led by lactobacilli, most often Lactobacillus kefiranofaciens, L. kefiri and L. parakefiri, along with Lactococcus and Leuconostoc species and acetic acid bacteria such as Acetobacter.181 The yeasts matter just as much. Kluyveromyces marxianus and Saccharomyces unisporus are two of the common ones, and a large population of yeasts is one of the features that sets kefir apart from other fermented milks.181

When one trial measured its kefir, it held 50 million lactic acid bacteria per milliliter, which works out to roughly 12 billion in a cup.17 Each batch varies in its exact mix of microbes, depending on the grains and the milk.2 That variety is the reason to enjoy kefir as a food, because each glass brings you a whole community of bacteria and yeasts working together, along with the lactic acid and kefiran they make.181 If you're new to probiotic foods, kefir is one of the richest places to start.

Kefir nutrition facts (per cup)

Calculated from USDA FoodData Central FDC ID 170904 (plain lowfat kefir) at the record's 1-cup weight of 243 grams; % Daily Value uses FDA adult label values.45

*Vitamins A and D in this lowfat kefir record sit far above what unfortified whole milk carries, so they most likely come from added vitamins; amounts vary by brand and by whether vitamins are added.416

A cup of kefir is a good source of the nutrients dairy is known for, led by vitamin B12, riboflavin, calcium, phosphorus and protein.45 It also carries a little vitamin K2, about 5 micrograms per 100 grams in two lab analyses, and kefir made with grains came out highest of six fermented milks in one of them.2627 The only plain kefir in USDA's SR Legacy database is a lowfat one, so full-fat kefir will run a little higher in fat and calories.4

Kefir carries less lactose than the milk it started as, because its bacteria release lactase, the enzyme that breaks lactose down, as they ferment the milk.2 A cup of plain lowfat kefir holds 9.0 grams of lactose, against 12.3 grams in the same weight of whole milk, about a quarter less.416 Most of kefir's 11.2 grams of sugar is that remaining lactose, since plain kefir has no sugar added.4

How does kefir work in your body?

Kefir does its work in two places: in the jar, where its grains ferment the milk before you ever drink it, and in your gut, where its live microbes arrive and help shift the bacteria living there toward friendlier groups. At room temperature, between 65°F and 85°F, the bacteria and yeasts in the grains spend about a day eating lactose and turning it into lactic acid, carbon dioxide, a little alcohol and more kefiran, which is why the milk thickens, sours and starts to fizz.2118

That head start matters for your digestion: when people who digest lactose poorly drink plain kefir, far less undigested lactose reaches the colon, where it would otherwise feed the gas and bloating they know too well.6

Then kefir's microbes reach your gut, where L. kefiri, one of kefir's own species, has turned up in the stool of people drinking it.17 And kefir is one part of a bigger fermented-food picture, because in a randomized 10-week Stanford study of 36 healthy adults, the 18 assigned to fermented foods built up to about six servings a day of foods like yogurt, kefir and kombucha, and their gut microbes grew more diverse while 19 of 93 inflammatory proteins in their blood came down.28

Follow a glass of kefir from the jar to your gut:

Kefir benefits

Which kefir is best: goat, sheep, cow or coconut?

If you want to get more probiotics in your diet, kefir and yogurt are the best, and I typically recommend goat's milk kefir or sheep's milk yogurt.15 Raw or organic goat's milk kefir is my second favorite milk, after canned coconut milk, and its protein is A2 casein.47 I tolerate goat's milk in small amounts pretty well, but if I do cow's milk, I don't do as well with it.23 Cultured A2 cow's milk kefir is an option if you tolerate it.

At the store, buy plain kefir and sweeten it yourself, because flavored kefirs can carry added sugar, and choose full-fat.322 The label should list live and active cultures.2 Commercial kefir can be made with freeze-dried starter cultures instead of grains,1 and in the cholesterol pilot above, the kefir made with traditional organisms did more than a commercial one,41 so homemade kefir from real grains is worth the small effort. The side effects section below covers who should stick with pasteurized milk, and for everyone else, raw milk from a farm you trust makes excellent kefir.

Water kefir and coconut kefir

If dairy doesn't agree with you, coconut kefir, coconut yogurt or coconut milk are great replacements,10 and coconut kefir still gives you live cultures, which makes it a good option for vegans too.3 If you're healing a leaky gut, water kefir and coconut yogurt are among the foods you can eat freely in the Healing Leaky Gut Protocol once fermented foods come back in, a tablespoon at a time, and coconut kefir is one of the fermented foods in the Rebuild phase of the Candida Cleanse.4820

Water kefir is lighter and sweeter than milk kefir and tastes a little like a fizzy soda.2 In a 2-week study of 40 healthy adults with no comparison group, who drank 200 mL a day of homemade water kefir, their gut bacteria shifted, with Bacteroidetes up 21.6% and Actinobacteria up 14.8%, and Bifidobacterium among the groups that rose.49 That makes water kefir an easy dairy-free way to bring cultures back to your gut.

Kefir vs. yogurt: which has more probiotics?

Kefir typically carries more kinds of live microbes than yogurt, though both are fermented milks full of live cultures, and both belong in your fridge. The difference starts with who does the fermenting. Yogurt is made by bacteria alone, while kefir's grains bring yeasts along with the bacteria, and that yeast population adds to what kefir can do.218 By Colorado State University Extension's figures, yogurt typically carries 1 to 5 live bacterial species and around 6 billion CFUs, and kefir up to 50 live species and over 20 billion.2 Kefir is also thinner, so you can drink it from a glass, while yogurt is the one you eat with a spoon. Our full kefir vs. yogurt guide compares them side by side.

How much kefir should you drink a day?

As I put it on my show, "Add in one fermented food a day, or at least every other day, and it could be something as simple as a couple tablespoons of coconut kefir in a morning superfood smoothie."11 That small start gives your gut time to adjust. In my Anti-Inflammatory Reset, kefir comes in during the gut-lining Repair phase at 2 to 3 tablespoons a day,12 my Healing Leaky Gut Protocol starts fermented foods at a tablespoon a day and works up to ¼ cup,48 and my Healthy Weight & Metabolic Reset uses a full cup.13

Any time of day works, and breakfast is an easy place to begin. The first phase of the Metabolic Reset calls for 30 grams of protein within an hour of waking, with Greek yogurt or kefir among the options, and a cup of kefir covers 9.2 grams of that.134

How to make kefir at home

Kefir is extremely easy to make in your own home,22 and all you need is milk, a jar, a cloth, a rubber band and some kefir grains.2 Goat's or sheep's milk makes a wonderful batch. Skip ultra-pasteurized (UP or UHT) milk, which has been heated to 275°F or higher, enough to change some of its proteins.2

1. Clean your gear. Wash a quart glass jar, a plastic or wooden spoon and a fine plastic or stainless steel strainer with plain dish soap, not an antimicrobial one.2
2. Add grains and milk. Put 2 tablespoons of active milk kefir grains in the jar, pour in 2 cups of milk and stir gently.2
3. Cover and wait. Cover the jar with two layers of cheesecloth or 2 or 3 coffee filters, secure it with a rubber band, and set it in a dark spot between 65°F and 85°F for 18 to 24 hours.2
4. Check it. It's ready when it's slightly thickened and smells pleasantly sour. If you test it, the pH should be between 4.0 and 4.5.2
5. Strain and start again. Strain the kefir into a clean jar with a lid and refrigerate it, then put the grains back in a clean jar with fresh milk.2

If a yellow, watery layer forms, that's whey separating out. You can pour it off or stir it back in, and next time ferment for a shorter time or add a little more milk.2 Your grains will grow as you go, so you'll soon have extra to share or to start a second jar.1

How to make water kefir

Water kefir uses its own grains. Traditionally, they go into a sugar-water solution of about 8%, roughly ⅓ cup of plain sugar per quart of water, with a few dried figs and some lemon slices, and ferment for 1 to 2 days at room temperature.19 The grains eat the sugar as they work, and you end up with a cloudy, fizzy, straw-colored drink that's low in sugar, tart and slightly alcoholic.19 Strain out the grains, refrigerate the finished drink, and feed the grains a fresh batch of sugar water.

How to make kefir cheese

Kefir cheese is soft and spreadable, made the same way labneh is made from yogurt. Line a strainer with a clean cloth or a coffee filter, set it over a bowl, pour in plain kefir, and let it drain in the refrigerator overnight, or up to a day for a thicker cheese. Stir in a pinch of sea salt and fresh herbs, and use the drained whey in smoothies. It's a close cousin of quark, another soft, fresh cultured cheese.

How to use kefir

Kefir works anywhere you'd use buttermilk, yogurt or sour cream, and it can stand in for milk or cream in cooking.222

More ways to use it:

• Mashed potatoes or sweet potatoes: mash them with kefir and a little ghee in place of milk.
• Kefir cheese: spread it on crackers or toast, or dollop it on roasted vegetables.
• A marinade: soak chicken in kefir with garlic and lemon, the way cooks use buttermilk.
• Desserts: freeze sweetened kefir with fruit into ice pops, or layer it with berries.
• Water kefir in place of soda or juice: pour it over ice with a squeeze of lemon.
• Water kefir in smoothies: use it as the liquid when you want a dairy-free blend.

Kefir recipes

These recipes start with plain goat's or sheep's milk kefir, or coconut kefir if you skip dairy, sweetened with fruit or a little raw honey. The first six come with full recipes, and nine more ideas follow.

Goat milk kefir breakfast bowl with figs and walnuts

I've described a biblical longevity day that starts just this way: "You could wake up in the morning and have some goat milk kefir, some figs, some walnuts and raw honey."23

Coconut kefir chia bowl

This dairy-free bowl is a breakfast from the Candida Cleanse meal plan: coconut kefir with ground flax, chia, cinnamon and berries.20

Berry kefir smoothie with collagen

Kefir with berries and collagen is a breakfast smoothie on the biblical diet meal plan, and the SIBO Protocol uses a similar blend of strawberries, kefir and protein.2250

Kefir overnight oats with cinnamon and berries

The Anti-Inflammatory Reset's meal plan pairs kefir with berries and ground flax, and soaking oats overnight in kefir turns that into a grab-and-go breakfast.12

Creamy kefir herb dressing

Kefir makes a tangy ranch-style dressing without the bottled kind's additives.

Kefir-marinated chicken

Kefir can stand in for buttermilk in recipes,2 including a buttermilk-style marinade that keeps chicken juicy.

More kefir recipes and ideas

• Pomegranate kefir bowl: I've called kefir or yogurt with pomegranates one of the best combos you could ever have, so spoon the arils over a bowl of plain goat's milk kefir.23
• My mom's kefir and flax: stir ground flaxseed into a bowl of goat's milk kefir, the way she ate it every day.39
• Kefir pancakes: use kefir in place of buttermilk in pancakes made with almond or oat flour, and top them with berries and a little raw honey.
• Sparkling water kefir: stir a splash of fruit juice into finished water kefir for a fizzy drink in place of soda.2
• Avocado ranch dressing: goat milk kefir and ripe avocado blended into a creamy dressing
• Cauliflower mac and cheese: cauliflower in a sauce of goat milk kefir and cheese
• Strawberry papaya smoothie: a dairy-free smoothie made with coconut kefir
• Borscht: the Eastern European beet soup, topped with a spoonful of goat milk kefir
• Kefir cheese toast: spread strained kefir cheese on sourdough and top it with sliced cucumber, olive oil and fresh dill.

Kefir side effects: who should go slowly

Kefir is a safe everyday food for most people, and a 2023 review of 16 randomized trials judged it safe for generally healthy people.51 A few points help you start well.

Gas and bloating at first. Some extra gas or bloating in the first week or so is common while your gut adjusts; in the 2-week water kefir study, 32% of people noticed more gas and 24% some bloating, mild and passing.49 Start with a tablespoon or two a day and build up from there.4812

A milk allergy, or dairy that doesn't agree with you. Milk kefir is still milk, so it isn't for anyone with a milk allergy. Some people react to any dairy at all, and I've had patients who get sick if they touch any type of dairy, even if it's raw and fermented.52 If that's you, coconut kefir and water kefir give you the cultures without the dairy.1048

Raw milk kefir. Unpasteurized milk from any animal can carry Listeria, E. coli and other germs, and the FDA names pregnant women, young children, older adults and people with weakened immunity as the most at risk.53 If you're in one of those groups, choose kefir made from pasteurized milk. For everyone else, the decision comes down to the farm.

Weakened immunity. Kefir was given safely to 54 critically ill adults in intensive care, with no bloodstream infections tied to it, though that study left out people on long-term immune-suppressing medicines.54 If you take a medicine that suppresses your immune system, ask your doctor before adding live-culture foods.

SIBO, Candida and histamine. The SIBO Protocol limits milk early on and brings in lactose-free yogurt or kefir later,50 and the Candida Cleanse uses coconut kefir in its Rebuild phase.20 If you're sensitive to histamine, go slowly with kefir, as with other fermented foods, and see how you feel.

Alcohol. Traditional kefir carries a trace of alcohol, from about 0.5% to 2%, which matters if you avoid alcohol completely.19

Medications (interaction check: Moderate). Kefir is dairy, so dairy's timing rules apply. Don't take the antibiotic ciprofloxacin with kefir or other dairy alone; its label allows it as part of a fuller meal.55 Milk can also blunt the absorption of the thyroid medicine levothyroxine, so take your dose with water and keep it apart from kefir as your prescription directs.56 Interactions are rated separately and don't change the score.

The bottom line

Kefir: frequently asked questions

References

1. Prado MR, Blandón LM, Vandenberghe LP, Rodrigues C, Castro GR, Thomaz-Soccol V, et al. Milk kefir: composition, microbial cultures, biological activities, and related products. Front Microbiol. 2015;6:1177. doi:10.3389/fmicb.2015.01177. PMID:26579086
2. Colorado State University Extension, FoodSmart Colorado. Understanding and Making Kefir. Reviewed October 2025.
3. Axe J. Ancient Remedies. Little, Brown Spark; 2021 ("Meals Are Medicine": kefir "one of the most microbe-rich foods in the world, with up to thirty-four different strains of bacteria in each serving" and "a staple of my diet"; plain goat's and sheep's milk kefir the healthiest kinds, coconut kefir a good option, especially for vegans; avoid versions with added sugar).
4. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Kefir, lowfat, plain, LIFEWAY. FDC ID 170904 (SR Legacy, NDB 1289; 1 cup = 243 g). Accessed November 4, 2026.
5. U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels.
6. Hertzler SR, Clancy SM. Kefir improves lactose digestion and tolerance in adults with lactose maldigestion. J Am Diet Assoc. 2003;103(5):582-7. doi:10.1053/jada.2003.50111. PMID:12728216
7. Yahyapoor F, Haghighat N, Sohrabi Z, Asbaghi O, Bagherniya M, Jamialahmadi T, et al. Effects of Kefir Consumption on Cardiometabolic Risk Factors: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Curr Drug Targets. 2023;24(7):599-612. doi:10.2174/1389450124666230427095742. PMID:37102491
8. Hamsho M, Ranneh Y, Kaddour B, Alfakhri S, Hacıbayram H, Shkorfu W, et al. Kefir: A Potential Gut Microbiota Modulator: A Systematic Review of Human Interventional Studies. Microbiologyopen. 2026;15(3):e70297. doi:10.1002/mbo3.70297. PMID:42036973
9. Bekar O, Yilmaz Y, Gulten M. Kefir improves the efficacy and tolerability of triple therapy in eradicating Helicobacter pylori. J Med Food. 2011;14(4):344-7. doi:10.1089/jmf.2010.0099. PMID:21186984
10. Axe J. Top 15 Remedies to Reverse Autoimmune Disease. The Dr. Axe Show. 2024 (coconut kefir, coconut yogurt or coconut milk as replacements for dairy at 14:38; YouTube https://www.youtube.com/watch?v=L7y0UzQPJF0&t=878s).
11. Axe J. 7 Foods That Quiet Inflammation Better Than Supplements. The Dr. Josh Axe Show. 2026 (traditional fermented foods, kefir among them, "reduce inflammation in a powerful way" at 18:29; one fermented food a day, "a couple tablespoons of coconut kefir in a morning superfood smoothie," at 27:39; YouTube https://www.youtube.com/watch?v=JFeUM50IzBI&t=1109s).
12. Axe J. The Anti-Inflammatory Reset: The 30-Day Healing Protocol. DrAxe.com protocol. 2026 (p. 18, Phase 3 Repair: "Add fermented foods — sauerkraut, kimchi, kefir (if tolerated), 2–3 tablespoons a day"; p. 21, 7-day meal plan: "Greek yogurt or kefir, berries, ground flax").
13. Axe J. Healthy Weight & Metabolic Reset: The 90-Day Healing Protocol. DrAxe.com protocol. 2026 (p. 20, Top 10 metabolic foods, No. 6: "Greek yogurt or kefir · 1 cup, if tolerated · Protein plus probiotics; choose plain"; Phase 1: "30 g of protein within an hour of waking — eggs, Greek yogurt or kefir").
14. Axe J. The #1 Supplement to Heal Your Gut, Burn Fat, and Boost Immunity. The Dr. Josh Axe Show. 2025 (reintroducing dairy with highly fermented goat's or sheep's milk products at 8:04; "yogurt and kefir are my top one and two" at 57:50; YouTube https://www.youtube.com/watch?v=q-1THW9kLB0&t=484s).
15. Axe J. 6 Dangers of Meal Replacement Shakes. Dr. Josh Axe on YouTube. 2017 ("kefir and yogurt are the best" for probiotics and "I typically recommend goat's milk kefir or sheep's milk yogurt" at 18:45; YouTube https://www.youtube.com/watch?v=NC38oqElLzQ&t=1125s).
16. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Milk, whole, 3.25% milkfat, without added vitamin A and vitamin D. FDC ID 172217 (SR Legacy). Accessed November 4, 2026.
17. Yılmaz İ, Dolar ME, Özpınar H. Effect of administering kefir on the changes in fecal microbiota and symptoms of inflammatory bowel disease: A randomized controlled trial. Turk J Gastroenterol. 2019;30(3):242-253. doi:10.5152/tjg.2018.18227. PMID:30662004
18. Bourrie BC, Willing BP, Cotter PD. The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir. Front Microbiol. 2016;7:647. doi:10.3389/fmicb.2016.00647. PMID:27199969
19. Farag MA, Jomaa SA, El-Wahed AA, El-Seedi AHR. The Many Faces of Kefir Fermented Dairy Products: Quality Characteristics, Flavour Chemistry, Nutritional Value, Health Benefits, and Safety. Nutrients. 2020;12(2). doi:10.3390/nu12020346. PMID:32013044
20. Axe J. The Candida Cleanse Protocol. DrAxe.com protocol. 2026 (Phase 4 Rebuild, eat freely: "Sauerkraut, kimchi, coconut kefir"; p. 21, 7-day meal plan: "Coconut kefir with ground flax, chia, cinnamon & ½ cup berries").
21. St-Onge MP, Farnworth ER, Savard T, Chabot D, Mafu A, Jones PJ. Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810]. BMC Complement Altern Med. 2002;2:1. doi:10.1186/1472-6882-2-1. PMID:11825344
22. Axe J, Rubin J. The Biblio Diet. Hachette Book Group; 2025. ISBN 9781546008439 (milk and honey chapter: choose full-fat dairy "because the fat in dairy is crucial for calcium absorption," p. 74; kefir "raises immunity, builds bone strength, promotes digestive health, reduces allergies," is "extremely easy to make in your own home" and can be used in smoothies or in place of milk, yogurt or cream when cooking; raw milk is safe "if and only if you acquire it from a reputable source"; meal plan: kefir smoothie with berries and collagen).
23. Axe J. The Bible's Grocery List: 10 Foods That Slow How Fast You Age. The Dr. Josh Axe Show. 2026 (kefir or yogurt with pomegranates at 12:01; fermented dairy, Genesis 18:8 and probiotics at 30:33; "I tolerate goat's milk in small amounts pretty well" at 32:34; a biblical longevity breakfast of goat milk kefir, figs, walnuts and raw honey at 34:43; YouTube https://www.youtube.com/watch?v=9AnNi1umufc&t=1833s).
24. The Holy Bible, King James Version. Genesis 18:8. Project Gutenberg eBook #10.
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26. Tarvainen M, Fabritius M, Yang B. Determination of vitamin K composition of fermented food. Food Chem. 2019;275:515-522. doi:10.1016/j.foodchem.2018.09.136. PMID:30724228
27. Altuncu V, Kaymaz A, Ertekin Filiz B, Çubuk Demiralay E, Kök Taş T. Evaluation of MENAQUINONE-7 and fat-soluble vitamin production by starter cultures during fermentation in dairy products using RPLC method. Food Sci Nutr. 2024;12(11):9822-9833. doi:10.1002/fsn3.4474. PMID:39620019
28. Wastyk HC, Fragiadakis GK, Perelman D, Dahan D, Merrill BD, Yu FB, et al. Gut-microbiota-targeted diets modulate human immune status. Cell. 2021;184(16):4137-4153.e14. doi:10.1016/j.cell.2021.06.019. PMID:34256014
29. Fathi Y, Ghodrati N, Zibaeenezhad MJ, Faghih S. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women: A randomized controlled trial. J Clin Lipidol. 2017;11(1):136-146. doi:10.1016/j.jacl.2016.10.016. PMID:28391880
30. Tu MY, Chen HL, Tung YT, Kao CC, Hu FC, Chen CM. Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients. PLoS One. 2015;10(12):e0144231. doi:10.1371/journal.pone.0144231. PMID:26655888
31. Alves E, Gregório J, Rijo P, Rosado C, Rodrigues LM. The Impact of Kefir on Epidermal Water Homeostasis in Healthy Human Skin. Life (Basel). 2022;12(7). doi:10.3390/life12071075. PMID:35888163
32. Adiloğlu AK, Gönülateş N, Işler M, Senol A. [The effect of kefir consumption on human immune system: a cytokine study]. Mikrobiyol Bul. 2013;47(2):273-81. doi:10.5578/mb.4709. PMID:23621727
33. Salari A, Ghodrat S, Gheflati A, Jarahi L, Hashemi M, Afshari A. Effect of kefir beverage consumption on glycemic control: A systematic review and meta-analysis of randomized controlled clinical trials. Complement Ther Clin Pract. 2021;44:101443. doi:10.1016/j.ctcp.2021.101443. PMID:34280689
34. Hamsho M, Hawari R, Yeşil Z, Dakhel Z, Dursun Saydam D, Terzi M, et al. Effect of different kefir dosages on inflammation status, metabolic profile, and anthropometric measurements in adults: A systematic review and meta-analysis. Nutr Metab Cardiovasc Dis. 2026;36(5):104364. doi:10.1016/j.numecd.2025.104364. PMID:41076330
35. Ostadrahimi A, Taghizadeh A, Mobasseri M, Farrin N, Payahoo L, Beyramalipoor Gheshlaghi Z, et al. Effect of probiotic fermented milk (kefir) on glycemic control and lipid profile in type 2 diabetic patients: a randomized double-blind placebo-controlled clinical trial. Iran J Public Health. 2015;44(2):228-37. PMID:25905057
36. Kong KL, Hendrich S. Glycemic index, insulinemic index, and satiety index of kefir. J Am Coll Nutr. 2012;31(4):280-7. doi:10.1080/07315724.2012.10720435. PMID:23378456
37. Turan İ, Dedeli Ö, Bor S, İlter T. Effects of a kefir supplement on symptoms, colonic transit, and bowel satisfaction score in patients with chronic constipation: a pilot study. Turk J Gastroenterol. 2014;25(6):650-6. doi:10.5152/tjg.2014.6990. PMID:25599776
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40. Bellikci-Koyu E, Sarer-Yurekli BP, Karagozlu C, Aydin-Kose F, Ozgen AG, Buyuktuncer Z. Probiotic kefir consumption improves serum apolipoprotein A1 levels in metabolic syndrome patients: a randomized controlled clinical trial. Nutr Res. 2022;102:59-70. doi:10.1016/j.nutres.2022.02.006. PMID:35405603
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50. Axe J. SIBO Protocol. DrAxe.com protocol. 2026 (p. 20, milk and soft cheese limited in the Prepare and Clear phases; p. 21, 7-day meal plan: "Smoothie — strawberries, lactose-free yogurt or kefir, protein").
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Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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