The addition of 1, 3, or 6 g of cinnamon to the diet led to significant decreases in serum glucose levels after 40 days. Values after 20 days were significantly lower only in the group receiving 6 g of cinnamon (Table 1). At the levels tested, there was no evidence of a dose response because the response to all three levels of cinnamon was similar. Decreases ranged from 18 to 29%. After the subjects no longer consumed the cinnamon for 20 days, glucose levels were significantly lower only in the group consuming the lowest level of cinnamon. Glucose values in the three placebo groups were not significantly different at any of the time points.