How much coumarin is in a teaspoon of common store‑brand cassia cinnamon and how that compares to the EFSA TDI?
Executive summary
A single teaspoon of typical store‑brand cassia cinnamon contains on the order of about 7–18 milligrams of coumarin, a range supported by measurements of cassia ground cinnamon in retail markets [1] [2]. The European Food Safety Authority’s Tolerable Daily Intake (TDI) for coumarin is 0.1 mg per kilogram body weight per day, which equals 6 mg for a 60‑kg adult and 7 mg for a 70‑kg adult [3] [4]; that means one teaspoon of many cassia products can meet or substantially exceed the EFSA TDI for an average adult [1] [5].
1. How much coumarin is actually in a teaspoon of store‑brand cassia cinnamon?
Published analyses of ground cassia cinnamon sold in retail markets report very high and variable coumarin contents, with measured concentrations often in the range of about 2,650 to 7,017 mg coumarin per kilogram of powder—equivalent to roughly 2.65–7.02 mg per gram of cinnamon [2]. Using those measured concentrations, a teaspoon of powder (commonly taken as roughly 2–3 g in regulatory discussions) yields roughly 7–18 mg of coumarin per teaspoon, a figure cited directly in consumer health guidance on cassia versus Ceylon cinnamon [1] [2].
2. How that amount compares to the EFSA TDI, in plain arithmetic
EFSA’s TDI for coumarin is 0.1 mg/kg body weight per day [3] [4]. That translates to 6 mg/day for a 60‑kg person and 7 mg/day for a 70‑kg person [3]. Therefore, a teaspoon containing 7–18 mg of coumarin meets or exceeds the daily limit for an average adult in most of the reported range and can exceed it by two to three times at the high end [1] [2] [3].
3. What regulators and reviews say about real‑world risk and frequency
European authorities have flagged cassia cinnamon as the main dietary source of coumarin and have implemented maximum levels in certain foods; Germany’s BfR has advised moderation because sustained intake above the TDI could harm sensitive individuals [6] [5]. The BfR notes that a 60‑kg adult would reach the TDI if consuming about 2 g of cassia cinnamon with average coumarin content per day—consistent with the teaspoon arithmetic above—and that brief small exceedances for a week or two are unlikely to be hazardous, while chronic high intake is the principal concern [5].
4. Important caveats: species, variability and market reality
Not all “cinnamon” is the same: true Ceylon cinnamon contains only trace amounts of coumarin, while multiple cassia species regularly sold as ordinary supermarket cinnamon have far higher and widely varying coumarin contents [7] [2]. Market surveys and recent studies also document high variability, adulteration and fraud in commercial cinnamon supplies, which complicates any single‑number claim about “store‑brand” levels [8] [7]. That variability is why published per‑teaspoon ranges span roughly 7–18 mg rather than a single figure [1] [2].
5. Balancing the message: occasional use vs. regular consumption
Public‑health assessments (and EFSA’s conservative TDI) are designed to prevent chronic exposure; population surveys in some countries find average dietary coumarin exposure is well below the TDI for typical consumers, though high consumers or cultural groups using cinnamon frequently may approach or exceed it [9]. Regulators therefore advise moderation—substituting Ceylon cinnamon, reducing daily added amounts, or avoiding concentrated cinnamon supplements—rather than alarm, because short‑term, small exceedances are treated as less likely to cause harm than long‑term overexposure [5] [9].