Key takeaways
Kombucha is a fermented beverage made from black tea and something called a SCOBY (symbiotic culture of bacteria and yeast).
Fans of kombucha say the drink can lower blood sugar, improve cholesterol, boost mood, detoxify the liver, and more.
Most of what we know about kombucha’s benefits comes from animal studies; there is a significant lack of human trials proving any clear benefit.
Kombucha is safe for most people in moderate amounts, but it contains a small amount of alcohol as a result of the fermentation process, so some people shouldn’t drink it, and others may have mild side effects.
You might think you’re a health-conscious person, but how far does your commitment really go? Would you be willing to consume a drink brewed with something that looks and sounds like a high school science fair project to potentially improve your health? If you said yes, then keep reading. Kombucha is the beverage you get when you ferment tea with a SCOBY or a symbiotic culture of bacteria and yeast (in other words, a living, thriving colony of microorganisms…floating around in your tea). It sounds icky, but kombucha is rooted in many centuries of traditional Chinese medicine, and it may provide a wealth of health benefits thanks to the probiotics produced during the fermentation process.
You can brew kombucha yourself with a store-bought or homemade SCOBY, or you can take a shortcut and purchase one of the many commercial kombucha bottles sold at supermarkets. But why, exactly, should you do either of these things? Here’s what the experts (and research) have to say about the perks of drinking kombucha, which include everything from lower blood sugar and cholesterol to better energy, digestion, and liver health.
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8 health benefits of kombucha
According to Amy Burkhart, MD, RD, founder of The Celiac MD, most of what’s known about kombucha products comes from animal studies rather than human studies. Those results have been promising, spurring more investigation into this fermented beverage in ongoing human trials. Based on the evidence we have so far, here are eight potential kombucha benefits.
1. Improves gut health
The fermentation process of kombucha produces beneficial bacteria that can support gut health and improve digestion, says Lauren Manaker, MS, RD, a registered dietitian based in Charleston, South Carolina. These bacteria, known commonly as probiotics, are the same gut health superstars found in fermented foods like kefir, kimchi, and sauerkraut. They provide digestive benefits by helping to balance the gut microbiome, potentially alleviating issues like bloating and constipation, Manaker explains.
While the connection between probiotics and gut health is pretty clear, keep in mind that kombucha isn’t an exact science, so the quality or quantity of probiotics in any given kombucha drink cannot be guaranteed.
Sheri Gaw, RDN, CDCES, owner of The Plant Strong Dietitian and spokesperson for Dietitian Insights, points to a 2023 systematic review showing that the conditions during fermentation, such as the type of starter, duration of fermentation, and temperature, can influence the strains of bacteria and yeast that are produced.
Remember, too, that homemade kombucha will have a different probiotic profile than store-bought kombucha: “Generally, traditionally fermented kombucha contains live cultures that can contribute to gut health, but some commercial brands undergo pasteurization or filtration, which can reduce the number of beneficial bacteria,” says Manaker.
2. May improve cholesterol
Fans of kombucha like to talk about the drink’s positive effects on cholesterol, and while it’s a definite possibility, the research in humans is still developing.
A 2022 study looked at the cholesterol-lowering impact of a sea grape kombucha drink in mice. After four weeks, the drink lowered total cholesterol, triglyceride, and LDL cholesterol levels while raising HDL cholesterol levels.
The study noted that the cholesterol-improving activity of the kombucha drink was similar to a 250 microgram dose of orlistat, a medication that blocks fat absorption in the diet.
3. May lower blood sugar
Drinking kombucha could potentially benefit people with Type 2 diabetes, especially in helping them maintain blood sugar levels. A 2023 pilot study found that people with Type 2 diabetes who drank kombucha for four weeks had lower average fasting blood glucose levels—an effect that has also been seen in recent rodent studies—though the sample size was incredibly small at only 12 participants.
“The findings from this study are promising since it can be hard for people with diabetes to adhere to drinking only water,” says Gaw, while clarifying that more research is needed to support these results and determine the best daily dose of kombucha for people with Type 2 diabetes.
4. Boosts your productivity
While there isn’t universal agreement about the best time of day to enjoy kombucha, many people find that drinking it in the morning can provide a refreshing boost of energy and clarity.
“The natural caffeine and B vitamins present in kombucha may help combat that mid-morning slump,” Manaker explains. “Consuming kombucha before a meal may aid digestion by stimulating stomach acids and preparing the digestive system for food.”
Gaw agrees, noting that the one-two punch of probiotics and caffeine in kombucha can “really get things moving regarding digestion and energy levels.” That said, you can drink kombucha at any time of day or night (as long as it doesn’t keep you up!).
5. May lower anxiety
If you’ve heard that kombucha isn’t just good for your gut but might also benefit your brain, there may be some truth to that, but the evidence hasn’t caught up yet.
“There is a significant gap between the online health claims about kombucha’s impact on mental health and actual scientific studies on its effects on conditions like anxiety and depression,” says Dr. Burkhart.
However, Dr. Burkhart also says the kombucha-mental health connection is certainly plausible because of what we know about the gut-brain axis and how what we eat can affect our mental health; in other words, because kombucha can reduce inflammation, provide probiotics, and positively influence the gut microbiome, it’s entirely possible it could have a positive effect on anxiety. As one 2023 review puts it, though, we need more research before anyone can make that claim or even begin to recommend specific amounts of kombucha for mental health benefits.
6. Supports weight management
With the current obesity epidemic in the U.S., many consumers are looking for products that will help them burn their stubborn belly fat, and some believe kombucha can do that for them. But is it true? Not quite: Dr. Burkhart says no current research suggests that kombucha directly promotes weight loss or reduces belly fat, but it can support weight management by supplying you with beneficial probiotics, reducing inflammation, and helping you balance your blood sugar levels.
Basically, if you’re exercising and eating for weight loss, kombucha might give your current routine a boost, but like anything else, it’s important not to overdo it. Consuming excessive amounts of kombucha will add unwanted calories, says Dr. Burkhart, potentially contributing to weight gain rather than weight loss (so make sure you check the serving size of your favorite store-bought kombucha).
7. Improves liver health
People with healthy livers shouldn’t worry too much about taking nutritional steps to “detox” their bodies because detoxifying is your liver’s primary job. If it’s functioning correctly, it’s doing that for you! But people with certain liver conditions, particularly nonalcoholic fatty liver disease (NAFLD), may benefit from consuming foods and drinks with detoxifying properties like kombucha, at least according to a few recent rodent studies.
For example, a 2022 study found that the probiotics in kombucha reduced the severity of NAFLD and improved liver damage; a few years earlier, a 2019 study found similar results. However, these findings haven’t been replicated in human trials yet, so more research is definitely needed before experts can say drinking kombucha benefits people with liver damage.
8. Contains antioxidants
Like all other types of tea, kombucha contains antioxidants, which primarily come from the fermentation process. “The type of tea—black, green, or herbal—can contribute various antioxidant compounds, including polyphenols like flavonoids, which play a crucial role in combating oxidative stress in the body linked to chronic diseases and aging,” Manaker explains.
While not exclusively about kombucha, a 2020 study found that tea polyphenols have antioxidant benefits that may extend to protecting cells against certain types of cancer. A 2019 review of studies links the polyphenols in black tea, specifically, to a multitude of health benefits ranging from improved weight loss and blood pressure to reduced risk of cardiovascular events and stroke.
Kombucha side effects
Most people can safely drink a moderate amount of kombucha each day, but there are a few possible side effects you might experience based on what kombucha is and how it’s made.
A “buzz” or feeling of euphoria
The fermentation process used to create kombucha produces a very small amount of alcohol, says Gaw, which could leave you with a buzz if you consume multiple servings or excessive amounts. Generally speaking, though, Gaw says the amount of alcohol present in one serving of kombucha is usually not enough to cause this sensation.
However, you might feel very good after drinking kombucha (possibly even euphoric!), thanks to its high content of probiotics, vitamins, and minerals, notes Gaw. That said, this has yet to be presented in any scientific research and is primarily anecdotal at this point.
Dizziness
Similarly, Gaw says there have been some reported cases of dizziness as a side effect of kombucha, potentially as a result of reduced blood sugar in people with certain health conditions, especially when consumed excessively in a short period. On the other hand, she says there isn’t much clinical evidence supporting this, and most people who drink normal amounts of kombucha don’t experience any side effects.
To be on the safe side, Gaw recommends that people with diabetes or who take blood sugar-lowering medications speak with their healthcare provider or a registered dietitian before consuming kombucha.
Stomach discomfort
While kombucha can work wonders for digestion, Manaker says it’s important to be aware that some people will find it difficult to digest, especially if they have sensitive stomachs or certain digestive conditions. Kombucha is a fizzy beverage, and its carbonation and acidity may cause discomfort or worsen symptoms for people with digestive problems. Introduce your body to kombucha gradually while paying attention to how your stomach reacts.
“Generally, moderate consumption—around 8 to 16 ounces daily—can provide health benefits without overwhelming the digestive system, especially for those new to kombucha,” Manaker says, suggesting that people start with smaller quantities (such as 4 ounces), allow your body to adjust, then gradually increase your intake as tolerated.
Is kombucha safe for everyone?
Kombucha isn’t likely to be dangerous for the majority of people, but it’s also not recommended for some populations. Dr. Burkhart says you should not drink kombucha or only consume it under your healthcare provider’s supervision if you:
- Have yeast or mold sensitivities because it could cause an allergic reaction due to its fermentation process
- Are pregnant or breastfeeding, which may be a concern due to the alcohol created during fermentation
- Have a history of alcohol abuse (again, because of the small amount of naturally occurring alcohol)
- Are immunocompromised, because commercial kombucha lacks regulation and could be contaminated with potentially harmful bacteria
Some brands of kombucha may include a warning label, says Dr. Burkhart, based on where it’s manufactured and sold. This is likely due to the alcohol content of the beverage and compliance with state and federal laws, she explains, like California’s Prop 65 cancer warnings about potentially harmful or cancer-causing substances. That doesn’t mean your daily dose of kombucha raises your cancer risk all by itself—just that you need to consume it wisely, in appropriate amounts, and be aware of what you’re getting inside each of your favorite brands.
“While many commercially available kombucha options promote their probiotic content, it’s important to remember that not all kombuchas contain live probiotics by the time they reach consumers,” says Manaker. “Various factors can affect the viability of these beneficial bacteria, including pasteurization, prolonged shelf life, and storage conditions, [all of which can] unfortunately eliminate the live probiotics that are key to delivering gut health benefits.”
Read your nutrition labels carefully, Manaker advises, looking for terms like “raw,” “unpasteurized,” or “contains live cultures” to make sure you’re choosing kombucha that still has its probiotic properties.
Bottom line: Is kombucha good for you?
Kombucha can be packed full of probiotics, antioxidants, and B vitamins, all of which contribute to better health and wellness in a variety of ways: potentially lowering blood sugar and cholesterol, improving digestion, supporting weight loss, and protecting against disease. However, much of what we know about kombucha’s health benefits has only been shown in animal studies; human clinical trials haven’t caught up yet, though more and more researchers are taking an interest in whether this black tea drink is as beneficial for people as some think.
Ultimately, whether or not you add kombucha to your daily diet is up to you. If you tolerate it well without any side effects, drinking a moderate amount each day is likely to be safe—and equally as likely to be good for you in some way (though the jury is still out on the details).
Sources
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