Scientists are hoping that a fermented cold tea beverage that has been drunk by humans for 2,000 years could help treat Type 2 diabetes.
Kombucha – brewed using a slimy disc that is a symbiotic culture of bacteria and yeast (SCOBY), which is commonly called a “mother” or a “mushroom” – has exploded in popularity in recent years. And now scientists have called for large trials to examine whether drinking it can help reduce blood sugar levels among patients with type 2 diabetes.
It’s been linked to lower blood sugar levels in a small “feasibility study”. Scientists conduct these assessments to see whether or not there would be a benefit in conducting large-scale clinical trials.
The new assessment, conducted on 12 patients with type 2 diabetes, saw half drinking about eight ounces of kombucha every day for four weeks. The other half were given a placebo, or dummy, drink.
After a two-month break, they swapped over and drank kombucha or a placebo for four weeks. The research team from the US found that kombucha appeared to lower average fasting blood glucose levels after a month.
There was no difference noted among the group who consumed the placebo, according to the analysis, published in Frontiers in Nutrition. Fasting blood glucose levels are determined by taking a blood sample from participants who have fasted for at least eight hours.
Researchers called for a larger trial to confirm and expand upon these results. Study author professor Dan Merenstein, from Georgetown University School of Medicine in Washington DC, said: “Some laboratory and rodent studies of kombucha have shown promise and one small study in people without diabetes showed kombucha lowered blood sugar, 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. 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 variability in a person’s diet.”
Kombucha is believed to have originated in Northeast China – an area historically referred to as Manchuria – around 220 BC. It was reputed to have healing properties and its name is reportedly derived from Dr Kombu, a Korean physician who brought the fermented tea to Japan, as a tonic and curative for Emperor Inkyo.
It initially became popular in the West in the 1990s. Sandor Katz, a fermentation expert and author of The Art of Fermentation, said: “I first tried kombucha around 1994, when a friend of mine with AIDS started making and drinking it as a health practice.
“It was touted as a general immune stimulant, though claims of kombucha’s benefits have been extraordinarily varied and broad.”