In a recent three-month study, 43 non-insulin-dependent people with type 2diabetes were given either a daily dose of 1000 milligrams of cinnamon or a placebo.
At the end of the study, there was not a single difference between the two groups with regard to average blood sugars, insulin levels, or cholesterol.
In contrast, a previous study found that a daily cinnamon hit caused a dip in blood sugar and cholesterol in people with type 2. None of that first group was taking diabetes medicines, however, unlike the current group, most of whom were on diabetes medications.
Source: Medline Plus, Diabetes Care, September 2007