 The use of cinnamon to help treat diabetes remains controversial. We know that cinnamon is so good at controlling one's blood sugar that you can cheat on a diabetes test by consuming two teaspoons of cinnamon the night before your glucose tolerance test. Basically they make you drink some sugar water and see how well your body can keep your blood sugar levels under control. And if you eat those two teaspoons right when the test starts or 12 hours before, you can significantly blunt the spike. A half teaspoon of cinnamon does not seem to be enough, but about a teaspoon a day does appear to make a significant difference. A review of the best studies done to date found that the intake of cinnamon by type 2 diabetics or pre-diabetics does lower their blood glucose significantly. So what's the controversy? Well, as I described before, cassia cinnamon, also known as Chinese cinnamon, or probably what you're getting at the store if it just says cinnamon, contains a compound called cumarin, which may be toxic to the liver in high enough doses. Originally the concern was mainly for kids during Christmas time where they might get an above-average exposure, but more recently some researchers suggested that kids just sprinkling some cassia cinnamon on their oatmeal a few times a week might exceed the recommended safety limit. The bold values here are above the recommended upper limit. For little kids, just a quarter teaspoon of cinnamon a few times a week may be too much, and if you're eating that cinnamon-sprinkled oatmeal more than like every day, even adults can bump up against the limit. So a teaspoon a day of cassia cinnamon might be too much for anyone, but no problem, just switch from cassia cinnamon to say lawn cinnamon. You can get the benefits without the potential risks, right? Without the risks, yes, but we're not sure about the benefits. Nearly all the studies showing blood sugar benefits of cinnamon were done on cassia. We've just assumed that the same would apply for the safer cinnamon, say lawn, but only recently was it put to the test. Owing to the presence of that toxic compound, the Federal Institute for Risk Assessment in Europe has warned against consuming large amounts of the cassia cinnamon, suggesting a switch from cassia cinnamon to say lawn cinnamon, also known as true cinnamon. But we didn't know whether or not the true cinnamon had similar benefits until now. We saw that nice blunting of blood sugar levels in response to cassia cinnamon, but in response to say lawn cinnamon, nothing, bummer. In fact, they're thinking maybe that potentially toxic kumarine stuff was the active ingredient in the cassia cinnamon all along. So you take out the toxin, you take out the benefit. So they conclude, yeah, it's great that health authorities are recommending the switch, however the positive effect seen with cassia could then be lost. So should we give up on going out of our way to add cinnamon to our diet? No, I think it's still a good idea to shoot for about a teaspoon of cinnamon, of a say lawn cinnamon a day, since there's a bunch of other benefits linked to cinnamon, besides just blood sugar control. Not the least of which is its potent antioxidant content. In fact, one of the cheapest food sources of antioxidants, beating out the cloves and coming in just under purple cabbage. But cinnamon can no longer be considered a safe and effective treatment for diabetes. Either you're using cassia cinnamon and it's effective, but may not be safe, or using say lawn cinnamon, which is safe, but does not appear effective. But look, even the cassia cinnamon only brought down blood sugars modestly. In other words, only as good as the leading diabetes drug in the world, metformin sold as a gucophage, yeah it may work as good as the leading drug, but that's not saying much. The best way to treat diabetes is to attempt to cure it completely reversing diabetes with a healthy diet.