From gooey Christmas morning cinnamon rolls to snickerdoodles, gingersnaps, spice cake, and eggnog, cinnamon is a flavor we all associate with the holiday season. But before you go stocking your pantry for your holiday baking this year, take note: All those different bottles of cinnamon you’ll find at the supermarket are not created equally. As it turns out, you could be buying a bottle labeled “cinnamon” that’s something else entirely. Here’s what you need to know.

What is cinnamon, actually?

True cinnamon is Ceylon soft bark cinnamon (also known as Cinnamomum verum), which is made from the actual bark of a tree native to the islands of Sri Lanka, near the southern tip of India. This beloved spice has both benefited and plagued the people of Sri Lanka, putting them in a literal tug-of-spice war started hundreds of years ago with the Portuguese, says chef Elizabeth Johnson, researcher and owner of Pharm Table, an apothecary restaurant in San Antonio that’s based on a global spice library.

“What has ensued is deforestation and over-harvesting of a precious global spice that has made its way into the DNA of many global cuisines,” she adds. Ceylon cinnamon has been lauded for its ability to stabilize blood sugar as well as its perceived sweetness.

So what’s the “fake” cinnamon?

A plant called cassia (Cinnamomum cassia), by contrast, is native to southern China and spans a much larger territory, making it more readily available—and way cheaper. This is the stuff you often see sold as cinnamon sticks, says Johnson. Neither the aroma, flavor or texture are the same as that of Ceylon cinnamon, but the FDA doesn’t distinguish between the two. That’s why both show up in stores as just cinnamon.

You can technically use cassia and Ceylon interchangeably in recipes, and each will provide a slightly different flavor profile and intensity. But, most people probably won’t be able to tell. “Ceylon cinnamon is heady, sweet and spicy,” says nutritionist and former BBC food professional Gina Waggott, while cassia is more robust. “It’s a bit like the difference between a dark-roast coffee and a regular one,” she adds.

Flavor differences aside, this is the part worth paying attention to: All cinnamons have some amount of a natural compound called coumarin, which imparts flavor, but the amount found in cassia is considerably higher than that in Ceylon—and can even be toxic. Though cassia is considered safe in small amounts (up to 1 teaspoon per day), eating too much could be harmful because coumarin has carcinogenic and liver-damaging properties.

cinnamon   Credit: Getty / Westend61

Fillers in cinnamon

As if the coumarin risks weren’t scary enough, many cheaper cinnamons also add fillers. These can really be any additive that helps bulk up the product. (So that $2 bargain bottle you picked up? Not such a good deal after all.) Some companies will use an anti-caking agent to help lengthen the shelf life and prevent the spice from caking up inside the bottle. “When used in excess, though, they fill the bottle with less-expensive material that doesn’t add flavor, but helps reduce costs,” says Steve Finnie, brand director with Spice Islands.

One type of filler for cinnamon could be another type of bark that’s not rich in oils, which will dampen the flavor of the true oil-rich cinnamon bark. Here’s the real kicker, though: Per the FDA, any spice labeled cinnamon can technically have up to 5% insect-infested pieces by weight or 5% moldy pieces by weight and—get this—up to 1 milligram of “mammalian excreta” (we’re talking mouse poop, people) per pound. Oh, and rodent hairs, too—up to 11 per 50 grams. (Sorry if this is making all these healthy cinnamon recipes sound oh-so-unappetizing right now.)

How to buy high-quality cinnamon

cinnamon Credit: Getty / Westend61

cinnamon

Credit: Getty / Westend61