This double-blind, placebo-controlled study gave 34 prediabetics either placebo or 500mg of berberine 3 times a day for 12 weeks.
Compared to placebo, there was a significant improvement of 21.01% in fasting glucose, 19.68% in fasting insulin, 22.15% in 2-hour oral glucose tolerance test, 15.17% in HbA1c (the most important marker of long term blood sugar and diabetes control), and 33.39% in insulin resistance.
This study suggests that berberine can safely help prevent delay the progression of prediabetes to diabetes.
BMC Endocr Disord. 2023;23:190