Cinnamon for Type 2 Diabetes

What is the problem and what is known about it so far?
People with Type 2 Diabetes have two to four times the risk of developing cardiovascular disease and the resulting complications of heart attack, stroke and poor circulation than those without diabetes. Although there can be many causes of Type 2 Diabetes and cardiovascular disease, diet is thought to play a role in the severity of both diseases.

Why did the researchers do this particular study?
The dietary components beneficial for the prevention and treatment of these diseases have not been clearly defined, but it is thought that spices may play a role. Spices such as cinnamon, cloves, bay leaves and turmeric can enhance the activity of insulin which can improve glucose [blood sugar] metabolism and the overall health of individuals with Diabetes.

Who was in the study?
60 people with diabetes, 30 men and 30 women, over 40 years of age, volunteered for the study. Patients who were not taking insulin, not taking medicine for other health conditions, and who had fasting blood glucose levels of between 140 and 400 mg/dl were chosen for the study. The average age of the patients was 52 years.

How was the study done?
The study lasted 60 days. Patients were divided randomly into six groups. Group 1, 2 and 3 consumed one, three, and six grams of cinnamon daily. Group 4, 5 and 6 were given one, three, and six grams of a placebo [inactive] substance. (One gram is equal to about 1/5 of a teaspoon.)The cinnamon or placebo was consumed for 40 days followed by 20 days during which participants took nothing. At day 0, 20, 40, and 60, fasting blood glucose and cholesterol levels were checked.

What did the research find?
Subjects taking dietary supplements of cinnamon had levels of both glucose and cholesterol up to 30% lower after 40 days while those taking placebo showed no change. Improvement of glucose and cholesterol was similar in all groups using cinnamon regardless of the dose. These benefits were observed 20 days after stopping the supplements, perhaps demonstrating a long-lasting effect of cinnamon. No significant changes were noted in the placebo groups.

What were the limitations of the study?
The size of the study population was limited to only 60 people so may not be representative of many people with diabetes. Also, although the subjects were not using insulin, they were using other blood glucose lowering medications. The interaction of cinnamon and these medications was not taken into account. Two factors that suggest cause and effect, increasing effect with increasing dose and the effect disappearing when the treatment is stopped, were not demonstrated in this study. Finally the study was limited by the short period of time during which it was conducted (60 days). Although cinnamon did reduce lipid and glucose levels, the study did not address any long term effect of cinnamon on the cardiovascular system.

What were the implications of the study?
The study suggests that people with Type 2 Diabetes, or people with elevated blood glucose and cholesterol, may benefit from regular inclusion of cinnamon in their diet.

Summarized by Raphael Bielinski MD, Family Medicine Resident, Fletcher Allen Health Care, Burlington, Vermont
Summarized from "Cinnamon Improves Glucose and lipids of People with Type 2 Diabetes". Khan, A. et al. Diabetes Care, December 2003, Volume 26, Number 12, Pages 3215-3218.