Cinnamon is touted as extremely beneficial but it's important to understand that there are differences in the types of cinnamon. If you consume a lot of cinnamon, it's a good idea to know which one is best. There are two main types of cinnamon: Cassia and Ceylon. Ceylon is higher quality and safer in larger amounts. Cassia contains something called coumarin which can be harmful in large doses. You shouldn't eat more than one teaspoon a day of the cassia variety. Further information can be found here.