4 Potential Benefits Of Kombucha & How To Pick The Right Type

Kombucha has great PR. When many people think about gut health, their mind goes straight to the bubbly brew. However, the commercialization and growing demand for affordable, tasty kombucha have led to a few issues, including high levels of added sugar and varying levels of active compounds like probiotics. 

Kombucha is a bubbly drink that's made by combining green or black tea with sugar and Symbiotic Cultures of Bacteria and Yeasts, also known as a SCOBY.

A SCOBY is a gelatinous fermentation medium1 that contains acetic acid bacteria (AAB), lactic acid bacteria (LAB), and yeasts. The microorganisms in the SCOBY ferment the sugar, which results in a bubbly and tangy beverage that's high in health-promoting compounds such as probiotics, polyphenols, and organic acids.

Despite the recent buzz, kombucha has been consumed since ancient times. In fact, it was first brewed in China2 over 2,000 years ago, where it was prized for its detoxifying and energizing properties. Kombucha was introduced in Eastern Europe during the 20th century3 and gained popularity in the U.S. during the 1990s. 

You won't find the same microorganisms in every kombucha. For example, some kombuchas contain probiotic strains like Lactobacillus and Lactococcus, but these bacteria are not always present4 in kombucha brews.

Kombucha can also contain polyphenol antioxidants, amino acids, acetic acid, B vitamins, and minerals like zinc, iron, and manganese. But, again, the types and amounts of these substances can vary significantly between kombucha brands. 

"It's important to understand that not all kombuchas are the same," Amanda Sauceda, RDN, tells mindbodygreen. She points out that a 2022 study published in Nutrients that evaluated nine kombucha products found that all of the products had significant differences5 in antioxidant activities, metabolites, and probiotic types and concentrations. 

Since the production of kombucha isn't standardized, the final composition and health benefits of kombucha depend on the starter culture4, ingredients, fermentation time, sugar content, and more. 

While some research findings suggest that kombucha may promote health in several ways, most of these studies have been completed in animals or in test tubes. Human research investigating the potential health benefits of kombucha is limited at this time.

Kombucha can provide a variety of probiotics and other substances that are known to benefit gut health, such as LAB and polyphenol antioxidants.

LAB, like Lactobacillus and Lactococcus, have been shown to strengthen and improve the function of the intestinal barrier6 or gut lining by increasing mucus production, promoting the release of enzymes that inhibit the growth of pathogenic microbes, reducing inflammation, and increasing the integrity of tight junctions that act as a barrier against pathogens.

Additionally, probiotic bacteria modulate gut bacteria composition by supporting the growth of beneficial bacteria. Kombucha can also contain yeasts known to positively impact gut health, such as Saccharomyces species, as well as antioxidant and anti-inflammatory compounds.

Kombucha contains several substances that may help support blood sugar regulation like acetic acid, a byproduct of fermentation that has blood-sugar-lowering effects.

A small 2023 pilot study published in Frontiers in Nutrition found that when participants with diabetes drank 240 milliliters of kombucha for four weeks they experienced a significant 29% reduction in their average fasting blood sugar7 compared to baseline.

Another recent study demonstrated that drinking kombucha alongside a high glycemic index meal helped reduce the meal's impact8 on blood sugar levels compared to soda water. Researchers suggest that kombucha helps slow down the digestion and absorption of starches, which can help lower blood sugar levels.

While there's no evidence that drinking kombucha can lower heart disease risk in humans, several animal studies have found that a kombucha-rich diet may be effective in reducing high levels of blood lipids9, like LDL cholesterol.

Results from animal studies also suggest that kombucha may have anti-atherosclerotic properties. Atherosclerosis is the thickening or hardening of the arteries caused by a buildup of plaque and is the main cause of heart disease.

Kombucha may help protect heart health through several mechanisms, including decreasing the intestinal absorption of fat and reducing inflammation10.

In addition to the potential health benefits listed above, findings from test tube and animal studies suggest that kombucha may support health in other ways, such as protecting against liver damage and improving immune function.

Kombucha can be enjoyed at any time of day as a lower-sugar alternative to sodas, energy drinks, sweetened teas, and other sweet beverages. However, keep in mind that most kombucha does have some caffeine, so be cautious when drinking it close to bedtime.

If you'd like to reap its potential blood-sugar-lowering benefits, try drinking kombucha alongside carb-rich meals, like pasta, rice dishes, and sandwiches. Though research is limited, some study findings suggest that drinking kombucha with carb-rich meals may help reduce post-meal blood sugar spikes8 and support healthier blood sugar levels.

Unfortunately, many kombuchas are high in added sugar, with some containing more than 16 grams (4 teaspoons) of added sugar per bottle.

Choosing kombuchas that contain less than 6 grams of added sugar per 8-ounce serving can help you keep your added sugar intake in check.

"Look for brews with minimal added sugars and devoid of artificial flavors or preservatives, which can detract from the natural fermentative process," Pedre advises.

Though there are shelf-stable kombuchas, most kombucha experts recommend reaching for refrigerated kombuchas. Refrigeration is necessary to keep the live and active cultures found in kombucha viable.

Some experts suggest purchasing "traditionally fermented" kombuchas. These contain tea, sugar, and SCOBY and are free from added probiotics; any probiotics contained within the beverage are a result of the natural fermentation process.

Some companies add probiotics to the finished product after pasteurization or to further enhance the health benefits of the brew.

Traditional kombucha naturally contains a small amount of alcohol (less than 0.5%). Hard kombucha, which has recently grown in popularity, is much higher in alcohol than traditional kombucha. It can contain upward of 8% alcohol, so it's important to read labels when shopping for booch. 

Though there are likely some positives to drinking kombucha, the benefits of kombucha are often overhyped in the well-being world. 

While there's clear evidence that diets high in fermented foods and drinks, such as yogurt, kefir, kimchi, and sauerkraut, can support gut health and even protect against certain diseases11, there's currently limited evidence that kombucha has any significant effect on human health.

Limited human studies suggest that drinking kombucha may help reduce blood sugar levels in people with diabetes and reduce the effect of high-carb meals on blood sugar. However, the rest of the health benefits linked to kombucha, such as promoting a healthy gut environment and supporting immune health, are based on test tube and animal research. 

Additionally, kombucha brews are not all the same and contain different bacterial strains, sugar content, and additives that have different effects in the body. 

Eating a diverse and probiotic-rich diet is a great way to support your gut microbiome—and kombucha is one of the few beverage options out there that are naturally high in probiotics. However, its array of probiotics varies from bottle to bottle.

The ingredients, fermentation time, sugar content, etc., all impact the health benefits of a brand's 'booch. And when you throw home-brewed kombucha into the mix, it becomes clear that it's tough to make blanket statements about kombucha's health benefits.

That said, if you like sipping kombucha from time to time, there's no reason to stop—especially if you drink it in place of higher-sugar options like soda and energy drinks. Just be sure to keep mixing things up and getting probiotics from other food sources too.

Though kombucha is considered relatively safe, it's not the right choice for everyone. Those who are pregnant and those who are immunocompromised are generally advised to avoid consuming unpasteurized products, like unpasteurized kombucha. Kombucha also contains small amounts of alcohol, making it unsafe for kids and pregnant people12. 

"The beverage's natural acidity, while beneficial in moderation, can be problematic for those with gastrointestinal sensitivity," Pedre notes. "Ginger kombuchas, although helpful for digestion, can also aggravate acid reflux in individuals who are sensitive."

There have been reports of people experiencing side effects like shortness of breath, throat tightness, headache, nausea, and vomiting after drinking kombucha, but these side effects aren't common. It's also possible to be allergic to kombucha, but, again, this isn't common.

Most dangers related to kombucha consumption are related to drinking home-brewed kombucha. Improperly brewed kombucha can be very acidic or contain contaminants that can harm your health. If you're making kombucha at home, it's critical to follow strict brewing and safety standards to avoid contamination with dangerous pathogens and to ensure the end product is safe to drink. 

Though some people swear by kombucha, human studies supporting its purported benefits are lacking and more research is needed to fully understand if kombucha (especially commercially made kombucha) is as healthy as it's hyped up to be.