Some studies have investigated the effect of cinnamon on blood sugar levels, but there aren't enough of them or enough carefully compiled results — or consistency in those results — to draw hard and fast conclusions yet. "There's not very much research on it," explains Philip A. Kern, MD, an endocrinologist and director of the Barnstable Brown Diabetes and Obesity Center at the University of Kentucky College of Medicine in Lexington. But there is potential.
The studies that have tried to measure the effects of cinnamon on blood sugar levels in type 2 diabetes have been small and not well controlled. In general, a reliable study is one that is large (at least 500 to 1000 patients), has patients randomly assigned to different groups, and is double blind — meaning neither the researchers nor the subjects know who is getting the treatment. That type of detailed and careful research just hasn't been done on the subject of cinnamon’s role in diabetes, says Dr. Kern, adding that the results of the small studies that have been conducted "are all over the place."
"Some say that the cinnamon does lower blood sugar or improves some other measure — some studies report a benefit, and some studies don't report a benefit," says Kern. His initial reaction was dubious, he admits, but after studying what little research is available, the effects of cinnamon are "probably something deserving of a larger study."
For instance, one study suggests that cinnamon may be effective in lowering blood sugar levels because it has a similar effect on the body as insulin, the hormone that people with type 2 diabetes produce in insufficient amounts.
Cinnamon: A Dash or a Dollop?
The amount of cinnamon needed to produce a positive effect is unclear. In some of the clinical trials, diabetic patients were given about 1 gram of cinnamon in a capsule — that amount of pure cinnamon is about the size of the tip of your pinkie finger.
Swallowing that much cinnamon powder would be downright painful (and probably not taste very good), so Kern says you shouldn't try to ingest cinnamon on your own in an effort to lower blood sugar. You also shouldn't chow down on a big cinnamon bun or sip a cinnamon latte, thinking you're getting a health benefit — even if additional research concludes that cinnamon is of benefit in lowering blood sugar and managing diabetes, Kern says you're still not getting a free pass for the sugar and calories.
So what's the take-away message? Kern believes it's not so much that people with diabetes should eat more cinnamon, but that "maybe [it] has a property that might be beneficial." He adds, "If you could figure out exactly what it is about cinnamon, you could design a drug that would target that beneficial property.”
So, Kern says, if anything does come of cinnamon as a blood sugar-lowering agent, the recommendations for patients with diabetes will be in the form of a new medication that has captured the properties of cinnamon, not necessarily dietary changes.