Kombucha is a fermented tea that is said to have numerous health benefits. According to a new study, the tea can also help improve blood sugar levels in people with type 2 diabetes.
A research team led by Dr. Robert Hutkins from the University of Nebraska-Lincoln investigated in a recent clinical study. The results are published in the journal Frontiers in Nutrition.
Kombucha for diabetes?
“Kombucha is a tea fermented with bacteria and yeast that dates back to 200 BC. was drunk in China,” the researchers report. The tea is associated, among other things, with positive effects on the intestinal flora, the immune system and inflammation.
Based on corresponding indications from previous research, the team has now examined in a clinical pilot study with 12 participants whether kombucha can lower blood sugar levels in people with type 2 diabetes.
“Some laboratory and rodent studies of kombucha have shown promise, and a small study in people without diabetes has shown that kombucha lowers blood sugar levels, but to our knowledge this is the first clinical study examining the effects of kombucha in people with diabetes” , according to study author Professor Dr. Dan Merenstein of Georgetown University School of Medicine.
One glass of Kombucha a day for four weeks
For the study, half of the participants drank kombucha (240 milliliters) daily for four weeks, while the other participants received a placebo drink. The fasting blood sugar level was determined at the beginning of the treatment and after one and four weeks.
After a two-month period to “wash out” the biological effects of the drinks, kombucha and placebo were swapped between the groups and drunk for a further four weeks, the researchers report.
Significant improvement in blood sugar levels
When evaluating the data, it became clear that after four weeks of kombucha consumption, the participants had significantly lower fasting blood sugar levels than the participants in the placebo group, the research team continued.
Kombucha reduced the average fasting blood sugar level from 164 to 116 milligrams per deciliter after four weeks, while the difference after four weeks with the placebo was not statistically significant.
The researchers point out how important the reduction in fasting blood sugar was by referring to the guidelines of the American Diabetes Association, according to which the blood sugar level before meals should be between 70 and 130 milligrams per deciliter.
Lactic acid bacteria, acetic acid bacteria and dekkera
The experts also examined the composition of the fermenting microorganisms in the Kombucha used to find out which ingredients are responsible for the effect. Above all, lactic acid bacteria, acetic acid bacteria and a form of yeast called Dekkera were detected in higher amounts.
“Different studies with different kombucha brands from different manufacturers show slightly different microbial mixes and abundances, however, the key bacteria and yeasts are highly reproducible and likely functionally similar between the different brands and batches,” explains Dr. Hutkins.
Larger clinical trials needed
Overall, the results of the pilot study suggest the potential of a dietary intervention with kombucha to lower blood sugar levels in diabetes. However, the significance remains limited due to the small number of participants and larger clinical studies are now required to verify the results. (fp)
