The study appeared in September's issue of Diabetes Care:
Effect of Cinnamon on Glucose and Lipid Levels in Non–Insulin-Dependent Type 2 Diabetes
It was a small study - 43 adults with type 2 diabetes. The intervention group took 2, 500 mg capsules of cinnamon daily. (One gram ground cinnamon is about 3/4 teaspoon.) The placebo group took capsules filled with wheat flour.
After three months, the cinnamon users failed to show improvements in blood glucose, insulin, or cholesterol levels.
One sticking point, participants in the current study were taking diabetes medications. Participants in the promising Pakistani study were not.
The jury is still out on cinnamon use.