Expert warns of hidden risks from excessive cinnamon consumption

Many people enjoy adding cinnamon to coffee, baked goods, and hot drinks as autumn arrives, but excessive consumption—especially of certain varieties—may not always be safe.

Concerns center on coumarin, a natural compound found in some types of cinnamon, which can affect the liver if consumed in large amounts regularly over long periods.

According to the Daily Mail, Cassia cinnamon is the most common variety found in stores and is mainly grown in Indonesia, China, and Vietnam. It is characterized by its dark reddish-brown color and strong flavor. Cassia cinnamon contains relatively high levels of coumarin, so excessive intake may increase the risks associated with this compound.

In contrast, Ceylon cinnamon—also known as "true cinnamon"—contains very low levels of coumarin. It primarily comes from Sri Lanka and is lighter in color with a milder, sweeter flavor.

Dr. Hyewon Gray, associate professor at the College of Public Health at the University of South Florida, said that Ceylon cinnamon is a more suitable choice for those who consume cinnamon daily or in large quantities due to its lower coumarin content.

The Daily Mail notes that the two types can be distinguished when buying cinnamon sticks: Ceylon cinnamon consists of multiple thin layers rolled together, while Cassia cinnamon is thicker, harder, and usually made of a single roll. For ground cinnamon, it is difficult to tell the difference, so it is advisable to check the label for the scientific name or country of origin.

Adding small amounts of cinnamon to food or baked goods occasionally poses little risk to most healthy people; however, daily consumption of large amounts of Cassia cinnamon may increase exposure to coumarin.

According to a 2022 food safety risk assessment, an adult weighing about 60 kilograms reaches the acceptable daily limit of coumarin at around 6 milligrams. On average, Cassia cinnamon contains about 3 milligrams of coumarin per gram, meaning that about 2 grams could approach this limit for someone of that weight.

The issue is not limited to cinnamon used as a spice; cinnamon supplements marketed for blood sugar control or weight loss may contain higher amounts, and cinnamon is also found in products such as protein bars, baked goods, breakfast cereals, and masala chai tea blends.

Warnings indicate that people with liver disease are especially advised to avoid excessive intake of coumarin-rich cinnamon. Dr. Hyewon Gray explains that individuals with fatty liver, hepatitis, or cirrhosis may have a reduced ability to process coumarin and should therefore be cautious when consuming large amounts.

Liver problems may not initially present clear symptoms, but warning signs include persistent nausea, loss of appetite, fatigue, or pain in the upper right abdomen. More serious signs include yellowing of the skin or eyes, dark urine, pale stools, and persistent vomiting.

Most healthy people do not need to stop consuming cinnamon as long as intake remains within typical amounts used as a spice. However, those who consume it daily or in large quantities can reduce coumarin exposure by choosing Ceylon cinnamon instead of Cassia. There is also no need for "detox" programs after eating cinnamon, as the liver naturally metabolizes and eliminates substances.

According to Dr. Hyewon Gray, associate professor at the College of Public Health at the University of South Florida, the main concern is not moderate use of cinnamon as a spice, but rather the regular, long-term consumption of large amounts of Cassia cinnamon or concentrated cinnamon supplements, especially among people with liver disease.