Cassia Cinnamon: Species, Flavor, Coumarin and How It Is Used

That jar of ground cinnamon from a US supermarket is most likely cassia. It’s the cinnamon most Americans know: hard, reddish-brown quills and a strong, sweet-hot powder. It isn’t one plant but the bark of three related Asian trees. Beyond flavor, the big difference from Ceylon cinnamon is coumarin, a natural compound European regulators limit, and BfR estimates that a 60 kg adult reaches the tolerable intake with about 2 g a day of cassia with average coumarin content.¹ If you use a lot of cinnamon, it’s worth knowing which one you’ve got.

At a glance

The three cassias

Ceylon cinnamon, Cinnamomum verum, is a separate species from Sri Lanka; see Ceylon vs. cassia cinnamon and Ceylon cinnamon. Related profiles: Saigon cinnamon and Korintje cinnamon. You’ll often see cassia called “bastard cinnamon,” but we found no source documenting the nickname.

Flavor and aroma

Cassia tastes stronger, hotter and more single-minded than Ceylon cinnamon. It’s sweet and a little peppery, with a candy-like punch, where Ceylon is milder and more layered. The chemistry backs that up:

• Cassia. PROSEA gives Chinese cassia bark oil as 70–95% cinnamaldehyde with only traces of eugenol. The bark holds 1–4% essential oil.²
• Ceylon, for comparison. Ceylon bark oil is 50–75% cinnamaldehyde with 5–18% eugenol.⁴
• Coumarin. Among the less volatile compounds, coumarin is the only one that adds much to the taste and smell.²

How cassia bark is made

For Chinese and Vietnamese cassia, trees are first coppiced at 5–7 years, when they’re 1.5–2.5 m tall. The cut stems are ringed every 30–60 cm and split lengthwise so the bark can be peeled. Vietnamese cassia bark is also stripped from standing trees, sometimes from bamboo scaffolding. The bitter outer layer gets scraped off, and the bark dries in the sun, curling into reddish-brown quills. It’s graded mainly by type (scraped, unscraped, quills, quillings, featherings, chips) and looks, and it’s usually ground in the countries that buy it.²

History

What can be shown

• Herodotus. The Greek historian Herodotus described Arabians gathering cassia from a shallow pool guarded by winged creatures like bats, which they fended off by wrapping hides over everything but their eyes. It’s a traveler’s tale, not natural history. A companion story about cinnamon gathered from the nests of great birds often gets quoted next to it; we couldn’t open that chapter.
• The Bible. Psalm 45:8 in the King James Version describes garments that “smell of myrrh, and aloes, and cassia”.⁵ Strong’s lexicon defines the Hebrew word, qetsiah, as “cassia (a powdered bark)”, and this is its only appearance in scripture.⁶ The text can’t tell us whether that ancient bark was the same plant as today’s Chinese cassia.

What could not be confirmed

A few stories about cassia’s history get passed around: that the city of Guilin was named for cassia in the Qin dynasty, that Persian traders coined the name dar-chin (“wood of China”), that Jewish traders brought cassia to Europe, and that it caught on in the 19th century. Britannica says Guilin’s name means “Forest of Sweet Osmanthus”, not cassia, and notes that Guilin hasn’t been Guangxi’s provincial capital since Nanning replaced it in 1949.⁷ We found no source for the rest.

How cassia is used

• Baking and sweets. In Europe, cinnamon in general goes into baked goods and sweets, hot drinks and herbal infusions. Americans clearly prefer cassia over Ceylon cinnamon, and Vietnamese cassia in particular.²
• Savory and spice blends. Cassia, or Chinese cinnamon, is one of the five spices in Chinese five-spice powder, and cinnamon is a key ingredient in garam masala and masala chai. Whole quills go into braises, stocks and mulled drinks and come out before serving.
• Flavor industry. Chinese cassia leaf oil, usually just called cassia oil, matters a lot in cola-type drinks.²

For technique (sticks versus ground, when to add) see ground cinnamon vs. cinnamon sticks. For blends built on cassia, see apple pie spice and pumpkin pie spice.

Buying and quality

Ground cinnamon in a US supermarket is most likely cassia.⁸ BfR, Germany’s risk agency, says shoppers can hardly tell Ceylon and cassia apart, and notes that some packs say “Ceylon cinnamon”.³

Storage

No regulator or standards body publishes a shelf life for cassia, and the figures you’ll see online don’t trace back to anything. Keep it sealed, cool and dark, and go by smell: if a pinch of the ground spice smells faint, it’s faded.

Safety

Coumarin

Coumarin is the main reason to know which cinnamon you’re using if you use a lot of it. The European Food Safety Authority’s tolerable daily intake is 0.1 mg per kg of body weight, and EFSA judged that going three times over it for one to two weeks isn’t a safety concern.⁹ BfR says that in a small group of especially sensitive people, even fairly low doses can cause liver damage.³

BfR estimates that a 60 kg adult reaches the tolerable intake with about 2 g a day of cassia with average coumarin content, and a 15 kg child with about 0.5 g.¹ NCCIH says eating cassia doesn’t usually supply enough coumarin to cause real problems, but long-term use could matter for sensitive people, like those with liver disease.⁸

The EU sets no maximum for coumarin in cinnamon itself.³ It does limit coumarin in foods that contain cinnamon:¹²

Is coumarin a blood thinner? You’ll read that a lot. France’s food safety agency, ANSES, says the anticoagulant properties often credited to coumarins belong to dimeric derivatives like dicoumarol, and simple coumarins don’t have them. Drugs like warfarin are synthetic coumarin derivatives.¹³

Lead alerts

Since 2024 the US FDA has issued public health alerts on specific lots of ground cinnamon products found to contain elevated lead, with results it sums up as 2.03 to 7.68 parts per million.¹⁴ The alerts are about particular products, not cassia as a whole. The brand-by-brand list is on our cinnamon page.

Health claims

NCCIH says research doesn’t clearly support using cinnamon for any health condition, and it’s unclear whether cinnamon supplements help with diabetes or weight loss.⁸ The barks of all three cassia species are folk medicines for a long list of ailments,² but that’s tradition, not proven effect. We couldn’t support claims that cassia acts like insulin, fights food poisoning or is a good source of minerals, so we don’t make them.

Substitutes and comparisons

Ceylon cinnamon swaps in directly, with a milder flavor, and the barks are interchangeable in many uses. See cinnamon substitutes for other options, and cassia buds for the dried fruits of the same Chinese tree. Comparisons: Ceylon vs. cassia cinnamon, Saigon vs. Ceylon cinnamon, cinnamon vs. nutmeg and cloves vs. cinnamon. Overdid it? See too much cinnamon.