Researchers at the University of Ottawa, in Ontario reviewed the evidence for improved control of diabetes in type 2 diabetes mellitus.
First, the details.
Studies of cinnamon, fenugreek, Gymnema sylvestre (an Ayurvedic herb), green tea, fiber, momordica (bitter melon), chromium, and vanadium were reviewed.
Studies focused on the ability of these treatments to improve A1c (the best long-term evidence of diabetes control) and fasting blood sugar levels (a common way to test for diabetes and for short term blood sugar control).
And, the results.
Reduced A1c levels and fasting blood sugar levels in a large meta-analysis
Reduced A1c levels in 2 small studies
Improved fasting blood sugar levels
Its effects on A1c are unknown
No effect in 2 small studies
No consistent effect on A1c or fasting blood sugar levels in 12 small studies.
Green tea and fenugreek
Each reduced fasting blood sugar levels in 1 of 3 small studies
Reduced fasting blood sugar levels in small studies
There are no studies evaluating the effects of these complementary treatments on the complications of diabetes.
The bottom line?
The authors concluded the following.
Chromium and possibly Gymnema sylvestre appear to improve diabetes control.
Fiber, green tea, and fenugreek have other benefits but there is little evidence that they substantially improve diabetes control.
Further research on bitter melon and cinnamon is warranted.
One adjustment to this review, which was published in June 2009. This past September researchers reported, “Supplementation with 1 gram of cinnamon daily lowers A1c by 0.83% in patients with poorly controlled diabetes.”
John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at www.Vicus.com, a complementary and alternative medicine website.