A severely negative finding in the research into cinnamon as a treatment for diabetes was reported by researchers at
Dartmouth Medical Center in the . The USA researchers decided to test cinnamon as treatment for diabetics among a group of diabetics who need all the help they can get, adolescents with insulin-dependent, type 1 diabetes. The researchers set about to ascertain whether taking cinnamon would lower HbA1C levels in 90 days, indicating benefit for 24-hour blood sugar control. Dartmouth
However, HbA1C is usually a measure of the glycation of red blood cells over 120 days, not 90. It's almost as if the researchers wanted to make absolutely sure that cinnamon would not be helpful, so they took their measurements before it could have effect.
Altschuler JA, Casella SJ, MacKenzie TA, Curtis KM. The Effect of Cinnamon on A1C Among Adolescents With Type 1 Diabetes. Diabetes Care. 2007 Apr;30(4):813-6.