Kombucha, or fermented tea, has become a widely popular drink thanks to its distinctive taste and association with health benefits, although scientific research on it remains limited.

Gabriela Freis, a PhD student in Brazil, confirms she noticed an improvement in her gut health since she started having a little kombucha with lunch, becoming less bloated and more regular.

She enjoys the fizzy, slightly sour and sweet taste she prepares at home. However, on social media, claims go further, promoting the drink as a means to lose weight, control type 2 diabetes, and prevent heart disease and cancer.

Kombucha is made from tea, sugar, and a “symbiotic colony” of bacteria and yeast known as SCOBY. During fermentation, yeast converts sugar into alcohol and carbon dioxide gas, making the drink fizzy, while bacteria convert most of the alcohol into acids that give it a vinegar-like taste.

The resulting drink contains caffeine, beneficial plant compounds known as polyphenols, and a small amount of alcohol (-0.5% in commercial versions).

Although kombucha is naturally low in sugar, some manufacturers add sugar or fruit juices to make it sweeter, or flavor it with herbs and spices.

Most varieties retain live yeasts and bacteria, but some products are pasteurized or filtered to ensure longer shelf life, which may reduce microbial activity.

Potential Health Benefits

In a clinical trial involving about 60 overweight individuals, those who drank kombucha daily for 10 weeks did not achieve greater weight loss compared to others, but reported improvements in issues like acidity and bloating.

Another study with 16 participants showed no improvement in blood pressure, cholesterol, or inflammation markers. Blood sugar responses decreased by 20% in people who consumed a meal with kombucha compared to other drinks. Type 2 diabetes patients recorded a decrease in fasting blood sugar levels after 4 weeks of drinking one cup daily.

Experts believe research is insufficient to draw conclusions, but consuming a variety of fermented foods, including kombucha, yogurt, kefir, and kimchi, is generally associated with a healthier microbiome and reduced inflammation.

Doctors emphasize avoiding overestimating kombucha’s benefits, but see low-sugar varieties as a healthier alternative to sodas or alcoholic beverages.

Home preparation requires great care to avoid bacterial or mold contamination by purchasing SCOBY from a trusted source and maintaining a clean environment. If mold appears, it is advised to discard the entire batch.