There were three separate trials that evaluated the effects of cinnamon Cassia supplementation in patients with type 2 diabetes.  In 1990, Dr R. Anderson a researcher from The Human Nutrition Research Center of the FDA together with the USDA conducted a series of test on thirty Pakistani men and thirty Pakistani women with type 2 diabetes .They were divided into six groups at random.  Groups one through three were given a certain amount of cinnamon per day (group one-1 gram/day, group two-3 grams, group three-6 grams), and groups four through six were given placebos of the same doses of their respective groups one through three.  The test of cinnamon for diabetes lasted a period of 40 days.  After the final day, there were reductions in serum glucose levels with those who had actually received the cinnamon for diabetes (groups 1-3).  The researchers concluded that cinnamon (Cassia) safely reduced glucose levels in patients with type 2 diabetes. 

It was found, afterwards, that DR Anderson's test was impartial in the fact that he has a patent on the compound found to be the active ingredient in cinnamon.

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