Kombucha can rebalance gut ecosystem in obese people, even without dietary changes, claims study

A daily intake of kombucha made from black tea has been found to significantly influence the gut microbiome in adults—most notably in individuals with obesity—even without any changes to diet or exercise. The transformation of the gut environment was particularly noteworthy for its boost in beneficial bacteria that are known to help combat inflammation and support key metabolic functions.

Kombucha can be a game-changer for obese people

This conclusion comes from a groundbreaking clinical trial led by researchers at the Federal University of Viçosa in Brazil. Over an eight-week period, they monitored 38 adults (21 of normal weight and 17 with obesity) who consumed 200 ml of kombucha daily. To ensure the effects of the beverage could be accurately assessed, participants maintained their usual dietary and physical activity patterns.

Although the study wasn’t designed to directly measure weight loss, the changes in gut microbiota reflected improvements in health markers that often precede or support weight reduction. After the eight-week period, scientists conducted gut analyses and observed notable microbial shifts, especially in those with obesity. The patterns they uncovered closely resembled the microbial profiles of individuals with improved blood sugar levels and decreased inflammation.

One of the most prominent findings was the rise in Akkermansia muciniphila levels among participants. This bacterium is associated with reduced inflammation, enhanced insulin sensitivity, and a stronger gut barrier. Damage to this barrier, also known as the intestinal tight junction (TJ), has been linked to inflammatory bowel disease (IBD) and other inflammatory gut conditions.

"To the best of our knowledge, there is no clinical trial that has investigated the impact of regular kombucha consumption on the gut microbiota of humans, despite many companies claiming kombucha is a probiotic beverage," the researchers stated.

Another key shift was the increase in Subdoligranulum species, a genus known for producing the short-chain fatty acid butyrate—an important compound for blood sugar regulation and liver health. Additionally, there was a noticeable rise in Bacteroidota, a group of microbes that assist in digesting proteins and carbohydrates.

"A total of 145 phenolic compounds were identified in the kombucha, primarily flavonoids (81%) and phenolic acids (19%)," the study authors noted. "Kombucha favored commensal bacteria such as Bacteroidota and Akkermanciaceae, especially in the obese group. Subdoligranulum, a butyrate producer, also increased in the obese group after kombucha consumption. Obesity-associated genera Ruminococcus and Dorea were elevated in the obese group at baseline and reduced after kombucha consumption, becoming similar to the normal weight group."

While the study didn’t assess long-term health outcomes, the findings add to the growing body of evidence suggesting that gut health can be positively influenced through small, sustainable interventions—like the addition of kombucha—without the need for restrictive diets or drastic lifestyle changes.