Clinical trials are the way we prove drugs--and herbs--are safe and effective. In April of 2006 there had been one clinical trial that found that cinnamon was practically a wonder drug for type 2 diabetes, and a second clinical trial that found that it was of no value at all. Could is possibly that no single herb, like no single drug, is best for all type 2 diabetics?
That is what a German study published in May 2006 tells us. Giving volunteer diabetics either three placebo capsules a day or three 1,000 mg cinnamon extract capsules a day, the scientists concluded that:
"The cinnamon extract seems to have a moderate effect in reducing fasting plasma glucose concentrations in diabetic patients with poor glycaemic control."
The higher the starting blood sugar levels, the better the results of treatment. Perhaps cinnamon somehow "unclogs" the linings of capillaries so cells can accept sugar more readily from the bloodstream, and once it's done its job, there's nothing more for it to do. Or perhaps there is.
Mang B, Wolters M, Schmitt B, Kelb K, Lichtinghagen R, Stichtenoth DO, Hahn A. Effects of a cinnamon extract on plasma glucose, HbA, and serum lipids in diabetes mellitus type 2. Eur J Clin Invest. 2006 May;36(5):340-4.