Drinking Kombucha is associated with decreased blood sugar levels in people with type 2 diabetes

Researchers found that type 2 diabetes patients who consumed kombucha over four weeks had lower fasting blood sugar levels than those who drank a placebo. This pilot study suggests a potential dietary intervention to help lower blood sugar levels in diabetics, laying the groundwork for a larger, more comprehensive trial.

Small pilot study suggests that larger trials are warranted to confirm the potential benefit of fermented tea.

People with type 2 diabetes who drank kombucha, the fermented tea drink, for four weeks had lower fasting blood sugar levels compared to when they consumed a similarly flavored placebo drink. This is according to results from a clinical trial conducted by researchers at Georgetown University’s School of Health, the University of Nebraska-Lincoln and MedStar Health. This finding from a 12-person pilot trial points to the potential for a dietary intervention to help lower blood sugar levels in people with diabetes and also establishes the basis for a larger trial to confirm and extend these findings.

This finding was reported in the journal Limits in nutrition on 1 August 2023.

History of Kombucha

Kombucha is a tea fermented with bacteria and yeast and was consumed as early as 200 BC. in China, but it only became popular in the United States in the 1990s. Its popularity has been bolstered by anecdotal claims of improved immunity and energy and reduction of food cravings and inflammation, but evidence for these benefits has been limited.

“Some laboratory and rodent studies of kombucha have shown promise, and a small study in people without diabetes showed that kombucha lowered blood sugar, but as far as we know, this is the first clinical trial to examine the effects of kombucha in people with diabetes. ” says study author Dan Merenstein, MD, professor of Human Sciences in Georgetown’s School of Health and professor of family medicine at Georgetown University School of Medicine. “A lot more research needs to be done, but it’s very promising.”

Study Design and Results

Merenstein continued, “A strength of our trial was that we didn’t tell people what to eat because we used a crossover design that limited the effects of any variation in a person’s diet.”

The crossover design had a group of people drink about eight ounces of kombucha or a placebo drink daily for four weeks, and then after a two-month period to ‘wash out’ the biological effects of the drinks, the kombucha and placebo were swapped between groups of another four weeks of drinking the drinks. Neither group was told which drink they were given at that time.

Kombucha appeared to lower average fasting blood sugar levels after four weeks from 164 to 116 milligrams per day. deciliters, while the difference after four weeks with placebo was not statistically significant. Guidelines from the American Diabetes Association recommend blood sugar levels before meals should be between 70 and 130 milligrams per day. deciliters.

Kombucha composition and brand

The researchers also looked at the composition of fermenting microorganisms in kombucha to determine which ingredients might be the most active. They found that the drink consisted mainly of lactic acid acid bacteria, acetic acid bacteria and a type of yeast called Cover up, with each microbe present in roughly equal amounts; found was confirmed with RNA gene sequencing.

The kombucha used in this study was produced by Craft Kombucha, a commercial producer in the Washington, DC area. It has been re-branded as Brindle Boxer Kombucha.

“Different studies of different brands of kombucha from different manufacturers reveal slightly different microbial mixes and amounts,” said Robert Hutkins, Ph.D., University of Nebraska-Lincoln and the study’s senior author. “However, the key bacteria and yeast species are highly reproducible and likely to be functionally similar between brands and batches, which was reassuring for our experiments.”

The wider context

“An estimated 96 million Americans have pre-diabetes — and diabetes itself is the eighth leading cause of death in the United States as well as a major risk factor for heart disease, stroke and kidney failure,” said Chagai Mendelson, MD, lead author who worked in Merenstein’s laboratory in Georgetown while completing his residency at MedStar Health. “We were able to provide preliminary evidence that a common drink could have an effect on diabetes. We hope that a much larger trial, using the lessons learned in this trial, could be conducted to provide a more definitive answer to the effectiveness of kombucha in reducing blood sugar levels and thus preventing or helping to treat type 2 diabetes.”

Reference: “Kombucha tea as an antihyperglycemic agent in people with diabetes – a randomized controlled pilot study” by Chagai Mendelson, Sabrina Sparkes, Daniel J. Merenstein, Chloe Christensen, Varun Sharma, Sameer Desale, Jennifer M. Auchtung, Car Reen Kok, Heather E. Hallen-Adams and Robert Hutkins, August 1, 2023, Limits in nutrition.
DOI: 10.3389/fnut.2023.1190248

Additional study authors at Georgetown University are Sabrina Sparkes, a student in the School of Health, Varun Sharma and Sameer Desale. In addition to Hutkins, Chloe Christensen, Jennifer M. Auchtung, Car Reen Kok and Heather E. Hallen-Adams are at the University of Nebraska-Lincoln.

The authors wish to express their gratitude to Tanya Maynigo, founder of Craft Kombucha, for providing kombucha and placebo kombucha for this study. She teaches kombucha classes in Washington, DC, and this year is launching a new brand of her favorite drink called Brindle Boxer Kombucha.

The study received no external funding.

Hutkins is the co-founder of Synbiotic Health. Auchtung has a financial interest in Synbiotic Health. Merenstein is chairman of the International Scientific Association for Probiotics and Prebiotics Board of Directors, an unpaid position. All other authors have no competing interests to declare. All kombucha and placebo drinks were donated by Craft Kombucha. Craft Kombucha had no access to data reported in this study. No author has any financial ties to Craft Kombucha.