Since the insulin-like properties of cinnamon were discovered, many people have been taking it as a treatment or a prophylactic for insulin resistance and diabetes. In one of the videos on her Website, Nina Simonds recommends adding a whole teaspoon of cinnamon to your morning latte. (She is the author of A Spoonful of Ginger and Spices of Life, which emphasize the healthful properties of spices.) While one-half teaspoonful of cinnamon a day was the dosage that was recommended by the researchers who found it’s beneficial effect, many people assume that if a little is good, more is better. But there is a potential danger in taking too much or the wrong kind.
Cinnamon contains coumarin, an anti-coagulant and possibly carcinogenic substance that can cause liver inflammation. One source said that as little as three cinnamon cookies could contain enough of the toxin to harm a small child.
There are two kinds of cinnamon, but product labels do not usually identify the type. Ceylon or true cinnamon is a pale tan color; it is milder, sweeter, and more expensive than cassia. Cassia, or common cinnamon, is redder, stronger in flavor, and cheaper. Ceylon cinnamon sticks are tight rolls of thin layers; cassia sticks are hollow tubes of thicker, rougher, bark. Cassia cinnamon contains .5% coumarin, while Ceylon contains only .0004%.
An additional source for coumarin is vanilla. An extract of tonka beans, the seed of the Dipteryx odorata tree from Brazil, is often used as a substitute for vanilla, and some brands, especially ones from Mexico, may be contaminated with large amounts of the toxin. It has been illegal to sell products containing tonka bean extract in the US since 1954.
The European Food Safety Authority concluded that the TDI (tolerable daily intake) for coumarin is .0002 ounces per day, an amount easily exceeded during the Christmas season. There is no threat if the amount is exceeded for a short time only. (http://www.bfr.bund.de/cd/8487) The damage is reversible in a few weeks, but taking supplements made from powdered cassia bark regularly may not be such a good idea.
However, since coumarin is not water soluble, a water extract of cinnamon will not contain any of the hazardous compounds. I have gone back to adding a stick of cinnamon to the water I use for making tea while I am looking for a cinnamon supplement that states unequivocally that it is a water extract. I don’t know how to tell how much extract I am getting this way, especially since I reuse the sticks, but at least I can’t over-dose on it.
A little knowledge is a dangerous thing.
© 2008, Judy Barnes Baker