Kefir and kombucha are fermented probiotic drinks that may support gut health. But they differ in their ingredients, nutrition, and how they’re consumed. Kefir is a fermented milk drink with a yogurt-like consistency. Kombucha is a fermented tea that is typically carbonated and lightly sweetened.
As fermented foods, kefir and kombucha contain beneficial bacteria that may help support a healthy gut microbiome.
Kefir mainly contains lactic acid bacteria. It also provides antioxidant compounds produced during fermentation. Research suggests these beneficial bacteria and compounds may help support gut health by reducing inflammation. They may also increase the production of short-chain fatty acids (SCFAs), which help keep the gut lining healthy.
Like kefir, kombucha contains antioxidant and phenolic compounds, as well as acetic acid bacteria. These may help improve bowel regularity, support beneficial gut bacteria, and reduce inflammation.
Right now, there isn’t strong research showing that one is better than the other. If you’re choosing one for gut health, it ultimately comes down to taste preference.
Kefir and kombucha share some similarities. However, there are a few key differences between them. Here’s how the two compare.
Kefir
Kombucha
Base
Milk
Green or black tea
Starter culture
Kefir grains
Symbiotic culture of bacteria and yeast (SCOBY)
Fermentation time
19 to 24 hours
7 to 10 days
Flavor
Tangy, slightly sour
Slightly sour with a touch of sweetness
Texture
Creamy and slightly thick, similar to drinkable yogurt
Carbonated, lightly fizzy, and refreshing
Primary probiotic bacteria
Lactic acid bacteria and yeast
Acetic acid bacteria and yeast
Here’s how an 8-ounce serving of kefir and kombucha compare:
Kefir
Kombucha
Calories
127
40
Protein
8.76 grams (g)
0.25 g
Fat
2.34 g
0.02 g
Carbohydrates
18.3 g
9.84 g
Fiber
0 g
0 g
Calcium
303 milligrams (mg), or 23.3% of the Daily Value (DV)
0 mg, or 0% of the DV
Phosphorus
244 mg, or 19.5% of the DV
0 mg, or 0% of the DV
Vitamin A
425 micrograms (mcg), or 47.2% of the DV
0 mcg, or 0% of the DV
Riboflavin
0.42 mg, or 32.3% of the DV
0.06 mg, or 4.6% of the DV
Selenium
8.78 mcg, or 16% of the DV
0 mcg, or 0% of the DV
Vitamin D
2.44 mcg, or 12.2% of the DV
0 mcg, or 0% of the DV
Zinc
1.1 mg, or 10% of the DV
0 mg, or 0% of the DV
Caffeine
0 mg
28 mg
Kefir offers more nutritional value than kombucha. It provides protein, healthy fats, and several important vitamins and minerals, covering over 10% of your daily needs for:
CalciumPhosphorusVitamin ARiboflavinSeleniumVitamin DZinc
Kombucha is lower in calories but contains very small amounts of nutrients. Since it’s made from tea, it also has a small amount of caffeine, around one-quarter the amount found in a cup of coffee.
Nutrient content can vary widely by brand, especially since many kefir and kombucha products may contain added sugars or other ingredients.
While kefir and kombucha contain different probiotics and antioxidants, research suggests they may offer similar health benefits. Although research in humans is still limited, compounds in both drinks may:
Promote heart health: The antioxidants in kefir and kombucha may help support heart health by reducing oxidative stress and inflammation. Over time, this may help protect blood vessels and support healthy blood pressure and cholesterol levels.
Improve blood sugar control: While more research is needed, some data suggest kefir and kombucha may help support stable blood sugar levels. Kombucha contains acetic acid, which may help limit sharp rises in blood sugar after meals. Kefir contains probiotics that may help your body use insulin better.
Provide antimicrobial support: During fermentation, kefir and kombucha produce organic acids that may help limit the growth of harmful bacteria.
Support immune health: The probiotics and antioxidants in kefir and kombucha may help support immune health by strengthening the gut’s natural defenses.
Kefir also has more vitamins and minerals than kombucha. It is rich in calcium and vitamin D, which help keep bones strong. Kefir also contains protein, which helps you feel full and supports muscle health.
Some people may need to be cautious with fermented drinks, especially if they have food sensitivities, medical conditions, or take certain medications. Here are some things to consider:
Kefir contains dairy: It may not be suitable for people with a milk allergy or lactose intolerance.
Both have added sugar: Both beverages may contain added sugar. Consuming too much added sugar can increase the risk of weight gain, tooth decay, and type 2 diabetes.
May interfere with certain medications: Probiotic food and beverages may interact with certain medications, including immunosuppressants.
Could cause digestive upset: Drinking large amounts of fermented drinks may cause gas or stomach upset. If you’re new to fermented foods, start with a small amount.
Kombucha contains caffeine: Kombucha contains small amounts of caffeine, which may not be suitable for people who are sensitive to it.
Kombucha has some alcohol content: Store-bought kombucha drinks can contain very small amounts of alcohol, usually less than 0.5%. Homemade versions may contain more.
Both kefir and kombucha probiotic drinks can fit into a healthy diet. Ultimately, the best beverage for you comes down to your personal preference and dietary needs.
Choose kefir if:
You want more protein and nutrientsYou’re looking to boost your calcium and vitamin D intake
Choose kombucha if:
You prefer a dairy-free optionYou want a lower-calorie beverageYou enjoy a fizzy beverage and don’t mind a small amount of caffeine
Thanks for your feedback!
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Peluzio M do CG, Dias M de M e, Martinez JA, Milagro FI. Kefir and intestinal microbiota modulation: implications in human health. Front Nutr. 2021;8:638740. doi:10.3389/fnut.2021.638740
Fraiz GM, Bonifácio DB, De Paulo RS, et al. Benefits of kombucha consumption: A systematic review of clinical trials focused on microbiota and metabolic ealth. Fermentation. 2025;11(6):353. doi:10.3390/fermentation11060353
Chong AQ, Lau SW, Chin NL, Talib RA, Basha RK. Fermented Beverage Benefits: A Comprehensive Review and Comparison of Kombucha and Kefir Microbiome. Microorganisms. 2023;11(5):1344. doi:10.3390/microorganisms11051344
U.S. Department of Agriculture: FoodData Central. Tea, kombucha.
U.S. Department of Agriculture: FoodData Central. Kefir.
MedlinePlus. Calcium, vitamin D, and your bones.
Carbone JW, Pasiakos SM. Dietary Protein and Muscle Mass: Translating Science to Application and Health Benefit. Nutrients. 2019;11(5):1136. doi:10.3390/nu11051136
Centers for Disease Control and Prevention. Be smart about sugar.
Purdel C, Ungurianu A, Adam-Dima I, et al. Exploring the potential impact of probiotic use on drug metabolism and efficacy. Biomedicine & Pharmacotherapy. 2023;161:114468. doi:10.1016/j.biopha.2023.114468
U.S. Department of Agriculture. NALT full.
