Berberine has been used to treat type 2 diabetes for thousands of years. It lowers levels of blood glucose and helps the body use insulin more efficiently. It can also increase the effectiveness of diabetes drugs such as metformin.
Berberine has also been known to lower levels of LDL, or "bad" cholesterol, as well as triglycerides. Even after cardiovascular disease has been established, berberine can be helpful. According to some studies, it also appears to stop the growth of malignant tumors, including tumors of the breast, tongue, mouth, liver, pancreas, stomach and prostate. It also seems to work against leukemia and melanoma.