Sassafras is a deciduous tree native to eastern North America, with a long history of culinary use in Native American and early American cooking. Its leaves, roots, and bark contain safrole, once used to flavor root beer and other beverages until the FDA banned safrole as a food additive in 1960 after animal studies found it carcinogenic.
Dried, ground sassafras leaves remain in use today as filé powder, the thickening, flavoring spice central to Creole and Cajun gumbo, and the leaves can also be steeped into a tea with a root-beer-like flavor. Fresh sassafras root bark is no longer used in food, but the tree's leaves and other parts continue to appear in regional Creole, Cajun, and Appalachian cooking and in traditional herbal remedies.