Homemade fermented raw kombucha tea with different flavorings. H

Homemade fermented raw kombucha tea with different flavorings. (© sveta_zarzamora - stock.adobe.com)

LINCOLN, Neb. — New research suggests kombucha could help decrease blood sugar levels in individuals with Type 2 diabetes. Study authors speculate that consuming the popular fermented tea might serve as a method to manage the escalating blood sugar levels in patients.

A collaborative study conducted by scientists from Georgetown University, the University of Nebraska, and the non-profit health organization MedStar Health revealed that daily intake of an eight-ounce glass of kombucha over a four-week period reduced the blood sugar levels in patients. Conversely, diabetic participants who drank an equivalent amount of a placebo beverage with a similar taste did not experience any changes in their blood sugar levels.

Originating as early as 200 BC in China, the beverage filled with bacteria and yeast did not gain popularity in the United States until the 1990s. The belief that it enhances immunity and energy levels, reduces food cravings, and alleviates gut inflammation has sparked its appeal in the West. However, these claims are largely anecdotal and lack broad scientific proof.

“Some laboratory and rodent studies of kombucha have shown promise and one small study in people without diabetes showed kombucha lowered blood sugar,” says Professor Dan Merenstein from Georgetown’s School of Health, in a media release. “But to our knowledge, this is the first clinical trial examining effects of kombucha in people with diabetes. A lot more research needs to be done but this is very promising.”

two glasses full of tea
Photo by Katherine Sousa from Unsplash

In the study, one group consumed eight ounces of kombucha for four weeks, while the other group ingested a placebo beverage. After a two-month rest period, known as the “wash out” phase, the groups switched beverages. The participants were kept unaware of which beverage they were consuming at any point during the study.

Scientists found that kombucha reduced the average fasting blood glucose levels after four weeks, from 164 milligrams per decilitre to 116. Ingesting the placebo, however, showed no significant difference. The American Diabetes Association suggests that pre-meal blood sugar levels should ideally fall between 70 and 130 milligrams per decilitre.

RNA gene sequencing verified that the primary components of the drink were lactic and acetic acid bacteria, and a yeast strain called Dekkera. The researchers opted for Craft Kombucha, a commercial brand in the Washington DC area, which later rebranded its products as Brindle Boxer Kombucha.

“Different studies of different brands of kombucha by different manufacturers reveal slightly different microbial mixtures and abundances,” says the study’s senior author, Dr. Robert Hutkins, from the University of Nebraska-Lincoln. “However, the major bacteria and yeasts are highly reproducible and likely to be functionally similar between brands and batches, which was reassuring for our trial.”

The researchers emphasize blood sugar disorder poses a significant issue in the United States.

“An estimated 96 million Americans have pre-diabetes — and diabetes itself is the eighth leading cause of death in the U.S. as well as being a major risk factor for heart disease, stroke and kidney failure,” says co-author Dr. Chagai Mendelson, from MedStar Health. “We were able to provide preliminary evidence that a common drink could have an effect on diabetes. 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 we learned in this trial, could be undertaken to give a more definitive answer to the effectiveness of kombucha in reducing blood glucose levels, and hence prevent or help treat Type 2 diabetes.”

South West News Service writer Pol Allingham contributed to this report.

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  1. Evelyn says:

    What is this and where do you get it

    1. Dean says:

      Your favorite grocery store should have it… It should be a refrigerated section of the store. Be prepared, it’s about 4 bucks a 16oz bottle.

  2. Mark Ward says:

    Articles like this make BIG PHARMA VERY ANGRY.

  3. Esther Monk says:

    Where is this available