Researchers conducted a small preliminary study to see what happens when people drink black tea kombucha regularly. They had 36 adults—20 with normal weight and 16 with obesity—drink 200 mL of black tea kombucha daily for 8 weeks. They measured things like body weight, inflammation markers, and genes related to obesity before and after the intervention.
After 8 weeks, the study found changes in body weight, insulin resistance markers, and many inflammation and oxidative stress markers. They also saw changes in how certain obesity-related genes were expressed. The researchers noted these changes might be due to antioxidant compounds in the kombucha.
This was a very small study without a comparison group that didn't drink kombucha, so we can't say kombucha caused these changes. No safety issues were reported, but they weren't specifically tracked. The findings are early and need confirmation in larger, more rigorous studies before we can know if kombucha has real health benefits for obesity.