Hiroshima University researchers have found that fermented stevia extract may fight pancreatic cancer without harming healthy cells—potentially making it more than just a zero-calorie sugar substitute.
Pancreatic cancer shows significant resistance to existing treatments like surgery, chemotherapy, and radiation.
There’s a growing need to find new, effective cancer-fighting compounds—especially those that come from medicinal plants, said Danshiitsoodol.
Fermentation Unlocks Cancer-Fighting Power
The study, recently published in the International Journal of Molecular Sciences, found that when stevia is fermented with a probiotic, the resulting extract kills pancreatic cancer cells while sparing healthy kidney cells. The fermented extract inhibited cancer growth but did not harm normal cells.
“To enhance the pharmacological efficacy of natural plant extracts, microbial biotransformation has emerged as an effective strategy,” Masanori Sugiyama, a professor of microbiology and biotechnology and coauthor of the study, said in a press statement.
Sugiyama’s lab has studied more than 1,200 strains of bacteria from fruits, vegetables, flowers, and medicinal plants, evaluating their health benefits.
The results showed that the fermented stevia leaf extract (FSLE) was more effective at killing cancer cells than the nonfermented version.
Sugiyama said that FSLE was also less harmful to the HEK-293 cells, which are human kidney cells used in the study. Even at the highest dose tested, FSLE caused minimal damage to these cells.
Key Anticancer Agent Identified
Further analysis identified a compound called chlorogenic acid methyl ester (CAME) as the key anticancer agent. Fermentation reduced the amount of chlorogenic acid—a precursor to CAME—in the extract by sixfold, a change caused by bacterial enzymes, according to Danshiitsoodol.
“This microbial transformation was likely due to specific enzymes in the bacteria strain used,” she said.
CAME was found to stop cancer cells from multiplying, trigger them to self-destruct, and change the expression of key genes so that cells are more likely to die.
The experiments were conducted on cancer cells grown in laboratory dishes—not in living organisms. The researchers plan to conduct tests in mice to better understand how different doses of the fermented extract affect the entire body.
Stevia Safety and Benefits
Dr. Joseph Mercola, a board-certified family medicine physician not involved in the study, called the research “a powerful reminder” that plants like stevia offer more than just sweetness—they may deliver compounds that support long-term health.
Mercola noted that stevia extract is a “far healthier” alternative to artificial sweeteners like aspartame, sucralose, or saccharin. “Unlike synthetic options that can disrupt gut bacteria or trigger metabolic changes, pure stevia extract—which has a glycemic index close to zero—has minimal to no impact on your blood sugar or insulin,” he added.
However, he cautioned that sweeteners blended with stevia—such as those containing dextrose or maltodextrin—can raise blood sugar if taken in large amounts.
