The popular drink kombucha is a healthy alternative to sodas and juice

Kombucha is a low-calorie, low-sugar drink that’s healthier than popular options like soda and juice.
Kombucha also contains antioxidants, probiotics, and antimicrobial properties, though research is limited on how drinking kombucha may benefit your digestive tract, immune system, and more.
Kombucha’s nutritional content may vary depending on the brand, so always read the label before consuming it.
This article was reviewed by Samantha Cassetty, MS, RD, nutrition and wellness expert with a private practice based in New York City.
Visit Insider’s Health Reference library for more advice.

Kombucha can be found everywhere from your local café tap to the supermarket shelves. While it may appear to be a new trend, the truth is this fizzy fermented tea has been around for thousands of years.

Numerous kombucha brands tout the drink for its many health benefits, including improved digestion and immunity. But research is limited on just how beneficial kombucha really is.

Here’s what you need to know about kombucha before consuming this trendy beverage.

What is kombucha?

Kombucha is a fermented drink made with tea, sugar, yeast, and bacteria. A colony of live bacteria and yeast called SCOBY (symbiotic culture of bacteria and yeast) is added to sweetened tea, which is then left to ferment for one to three weeks before being carbonated and packaged. The result is a slightly fizzy beverage with a uniquely tart flavor.

Drinking kombucha has gone in and out of fashion over the past century, but its origins stretch back to China about 2,000 years ago. Back then, it was drunk for its supposed special healing and detoxifying properties.

Today, kombucha is a mainstream item sold worldwide in food stores and online, and it is offered in a variety of flavors. Some may drink it for its purported health benefits while others may drink it for pleasure.

The health benefits of kombucha

If you're drinking kombucha for your health, know this: Whatever miracle benefits you've heard about most likely came from a study in animals — if there was a study done at all.

A 2019 report analyzed 310 studies about kombucha and found that only one had actually examined the effects of kombucha in human subjects. The rest were either conducted in animals or in vitro — outside a living organism usually in cells or cultures in a test tube or petri dish.

Either way, the researchers conclude "it is critical that these assertions are tested in human clinical trials." So, the word is still out on whether kombucha can deliver on the various positive health assertions touted by many brands.

That said, kombucha may be a healthier option compared to other popular drinks like soda — starting with antioxidants.

Kombucha has antioxidants

A 2014 study revealed that kombucha also has a notable concentration of antioxidants, due primarily to the polyphenols in the tea.

Antioxidants have been shown to prevent cell damage by free radicals, thereby reducing the risk of chronic inflammation.

Chronic inflammation has been shown to have a number of detrimental consequences over the long term, including damage to your organs and joints. If left untreated, it may contribute to arthritis, heart disease, and Alzheimer's disease.

Kombucha contains probiotics

Probiotics are another one of kombucha's widely praised health benefits. Kombucha, much like other foods and beverages that go through a natural fermentation process, gains probiotic properties or "good" bacteria thought to improve digestion, support gut health, and help balance your microbiome.

A healthy gut is connected to numerous aspects of both physical and mental health — for instance, a 2018 report suggested that having a balanced microbiome can strengthen your immune system. Additionally, gut health has been linked to the development of dementia and chronic illnesses, like type 2 diabetes and cancer.

People who are trying to shift towards a diet that includes more whole foods may want to include kombucha as part of their nutrition plan because it may help restore proper gut health and improve nutrient absorption in the process.

Kombucha has antimicrobial properties

As a result of the fermentation process, kombucha also contains acetic acid, which has been shown to have antimicrobial properties. "Acetic acid can kill many harmful microorganisms such as Candida yeasts and other infection-causing bacteria," says RSP Nutrition consultant Mona Cabrera.

While there is no research confirming that kombucha can prevent these types of infections, acetic acid's antimicrobial powers are well-studied.

The health risks of kombucha

As long as you are in good health with no specific food intolerances, there are no serious risks to drinking a low-sugar kombucha.

However, kombucha may cause flatulence and general GI discomfort when you first start drinking it, so don't be alarmed if your body needs some time to get used to it.

"These issues usually resolve within a few days but if they persist for more than three to four days, I usually recommend discontinuing use," he says.

A small amount of alcohol is produced in the fermentation process of kombucha but for commercially available varieties sold in the US, the ABV is never more than 0.5%. Regardless, due to the trace amounts of alcohol and caffeine and the fact that it's unpasteurized, Cabrera recommends avoiding kombucha if you're pregnant or breastfeeding. Children should not drink kombucha if the ABV is 0.5% or higher.

Not all kombuchas are created equal, and given that nutritional content can vary depending on the brand, experts say it's worthwhile to look at the label before buying a product. According to Cabrera, a long list of ingredients is generally a red flag.

"The ingredient list should be short as it's just made from water, tea leaves, sugar, and SCOBY," she says. Make sure your drink does not have high amounts of added sugars or artificial sweeteners, which would decrease its health benefits, says Cabrera.

How often should you drink kombucha?

Provided you've established that your body can tolerate kombucha well you can drink it daily, says Sean Allt, nutrition coach at Innovative Fitness. He recommends starting with no more than 4 ounces per day to see how your body reacts to it before increasing your intake.

"If you respond well and enjoy it, you could consider increasing that to 8 ounces per day," he tells Insider.

Since kombucha does have a small amount of caffeine (approximately 10 mg in one 8-ounce serving), Cabrera advises drinking it earlier in the day if you're sensitive to the effects of caffeine.

If you don't like the taste of kombucha but you're interested in the gut health benefits, you may want to consider other fermented foods, such as sauerkraut, kimchi, kefir, or Greek yogurt.

Takeaways

Kombucha may not be the miracle elixir that it's marketed as, but experts concur it is a generally healthy beverage with multiple potential benefits.

Kombucha contains probiotics, antioxidants, and acetic acid, which have all been shown to promote positive health effects in the body.

Kombucha is not known to have serious health risks, but if you suffer from autoimmune issues, GI disorders, or you're pregnant, it's best to consult with a doctor before drinking it.