Background –  Over the past 10 years over 100 medical articles on cinnamon and diabetes have been published.  Partly because of these articles cinnamon is sold with labeling stating that it “Helps Maintain Healthy Blood Sugar Levels Already in the Normal Range” or “Promotes sugar and fat metabolism.”

Samples of the Evidence – Two studies illustrate the evidence for cinnamon improving blood sugar in diabetes.

In the first 109 patients were randomly assigned to their usual care for diabetes or given 1 gram cinnamon capsules for 90 days.   Patients taking the cinnamon capsules had average blood sugars 12 points lower. In the second of 79 patients taking an extract that was the equivalent of 3 grams of powder there was no improvement in average blood sugar.

Assessment – Many, but not all studies show a modest improvement in average blood sugar with cinnamon. The average lowering in studies is much less than the 40 points or more seen with the prescription medication, metformin which is available for 4 dollars a month.

Other Important Considerations.

Because cinnamon is a plant product, effectiveness may vary based on growing conditions and how the cinnamon is processed. There is currently no standard medical cinnamon preparation.  The main type of cinnamon studied is cassia cinnamon, which is sometimes known as Chinese cinnamon.  Less is known about the effects of other types of cinnamon. Cinnamon also contains a chemical called coumarin which has caused fatal liver failure in high doses.

Conclusion – Cinnamon, tastes good and evidence indicates it may modestly lower blood sugar in patients with diabetes.  Cinnamon is very unlikely to produce low blood sugars when combined with prescription medication. On the other hand even in the studies that found an effect, the improvement was not strong enough to eliminate the need for prescription medications for patients with diabetes.

 “What’s the Evidence?” provides scientific answers to your medical questions.  Two important aspects of an evidence based answer are: 1) Does it improve your life? Results in mice or only improving a blood test doesn’t count.  2) How good is the quality of the evidence? The best scientific evidence is a randomized double blind study. Randomized means patients are given a treatment based on chance. Double blind means neither the patient nor the study investigator knows which treatment is being given. This controls for our human biases for or against a treatment.

Although there is new medical information every day, not every question can be answered with the highest quality evidence. Also, not every scientific study reaches the same conclusion. In these cases you will have to weigh the evidence yourself to decide what is best.