Few beverages are getting as much attention as kombucha these days. Its devotees claim it has probiotic, anti-inflammatory, and even antioxidant benefits. Invented in China, the fermented drink adds certain strains of bacteria and yeast to black or green tea. Throughout seven to 10 days, the microbial mix (called a SCOBY) feeds off sugar and other ingredients to produce acetic acid and other acids. The result is a fizzy, slightly sour drink.
However, while the drink is generally considered safe, its health effects are mainly anecdotal and need validation. It is also a bit of a mystery how it works since the specific mixture of bacteria and yeast and the amount of acid produced by each batch can vary.
A new study published in Frontiers in Nutrition on Tuesday (August 1) suggests that these microbial byproducts may be behind the beverage’s benefits for diabetes. Researchers from Georgetown University, the University of Nebraska-Lincoln, and MedStar Health found that participants with type 2 diabetes who drank kombucha saw their morning fasting blood glucose levels drop. In contrast, those who drank a placebo did not. The results are “very intriguing,” says Dr. Rifka Schulman-Rosenbaum, director of inpatient diabetes at Long Island Jewish Medical Center in New York. “This is the first study of a beverage and its impact on diabetes, but more work is needed to validate these findings.”
The authors also found that kombucha lowered participants’ insulin resistance—a condition in which the body cannot use its insulin correctly—and improved their lipid profiles (cholesterol and triglycerides). “Our results suggest that dietary intake of kombucha can provide significant benefits for people with type 2 diabetes by improving their metabolic profile,” they write.
While the research is promising, experts still recommend a balanced diet and regular exercise when managing diabetes. In addition, patients should monitor their blood sugars using a meter at home and take their prescribed medications, according to Mendelson.
As for kombucha, “I would encourage someone with diabetes to talk to their healthcare provider before drinking it,” Kimberlain tells Healthline. “Especially if they are on medication because of the possibility of low blood sugar.”
The Sassy Dietitian is the editor of the website and a registered dietitian with a bachelor’s in journalism and a master’s in public health. She is based in Brooklyn, New York.
Kombucha, which contains bacteria and yeast, has been found to improve gut health. However, as with all foods and beverages, moderation is key.
The kombucha pictured above has a shallow sugar content, with only 4 grams per serving (1 teaspoon). Lower-sugar kombucha is available on the market. However, it is essential to note that all beverages have a small amount of ethanol—the byproduct of fermentation—and anything higher than 0.5 percent alcohol by volume is considered an alcoholic drink. The amount of ethanol in kombucha can vary depending on how it is made, so always consult your doctor before trying any new food or beverage.